A method and apparatus for Activity Environment Generator (“AEG”) is provided. The AEG allows a user in a variety of settings such as: domestic settings, office chairs, TV chairs, train seats, airplane seats, domestic or hospital beds. The AEG is particularly useful in the fields of rehabilitation, physiotherapy, injury prevention, falls prevention, training and wellness in general and may also provide recreational and/or entertainment elements. The AEG provides dynamically controllable forces with which the user interacts in the course of his/her activity. In one aspect of the invention, the forces provided by the AEG are generated by a magnetic field. In another aspect of the invention, the forces provided by The AEG are generated by a pneumatic actuator. The AEG is optionally scalable and/or modular and, in specific embodiments, may include one or more of the following: a Remote Trainer, an AEG-Accessory, an AEG-Wearable, optimization by Big Data and machine-learning.

The aim of the invention disclosed in this application is to provide an Activity Environment Generator ("AEG") apparatus and method that allow a user ("User") to create an Activity Environment and interact with the same, in a setting which is not, usually, designed and/or equipped for such Activity. Examples of typical settings include: domestic settings, office chairs, TV chairs, train seats, domestic or hospital beds and so forth.
The invention is particularly useful for exercises directed to the prevention of injuries caused by accidents such as falls of elderly people.
More generically, the invention is useful for the slowing down of physical decline due to aging, for persons of all ages who need rehabilitation following an injury, an illness or an accident, for treatment of particular health conditions, for physiotherapy and so forth.
The Activity Environment Generator may be particularly advantageous in situations that entail limited space, possibly for a prolonged time such as, for example, during a flight on an airplane where lack of sufficient physical activity may have serious health consequences.
All the above, without the need for costly and cumbersome systems which are unfeasible, impractical or costly for the kind of physical exercise and associated settings contemplated in this application.
The term "element" in this application means anything pertaining to AEG 2 that is physically or functionally necessary or useful in order to carry out the invention and its specific embodiment. The term "element" includes unit/s, component's, hardware, software, processes, data and any combination thereof.
The relationship between the elements is indicated by simple or bidirectional arrows according to the case.
If FIG. 2 an Activity Environment-Generator Master Unit, or in brief "AEG-MU", or "AEG-Master Unit", is indicated as 20.
AEG-MU 20 includes a Master Electromagnet (also referred to as "Master-EM") indicated as 21. The term "Electromagnet" means a type of magnet in which the magnetic field of the magnet is produced by an electric current. The term "Master", in relation to the Master Electromagnet 21 means that, based on the commands generated by the hereafter described Master Electromagnet Controller 24, Master Electromagnet 21 is able to determine the intensity, direction and timing of the interaction with other magnets and/or other magnetizable elements, as it will be described in detail hereafter.
AEG-SU 22 includes a Slave Magnet 23, or, in brief "S-Magnet". S-Magnet 23 can be an electromagnet or a permanent magnet, depending on the requirements of each specific embodiment and on different considerations such as, size and/or weight of the AEG 2 or of elements thereof, power consumption, intensity of the magnetic field and so forth.
More generally, Slave Magnet 23 may be of any suitable kind including, for example, permanent magnets, temporary magnets, electromagnets, fix polarity magnets, reverse-polarity magnets, electromagnetic circuits, etc.
Master Electromagnet Controller 24, controls all the operations of AEG-Master Unit 20, including Control Loop 25. Master Electromagnet Controller (or, in brief, "MEM-Controller") 24 also controls, directly and/or indirectly, the operations of AEG-SU 22 and, more in general, the whole of the operations of AEG 2. The term "Controller" in relation to Master Electromagnet Controller 24, includes the terms "controller", "processor", "CPU", "microprocessor" and any combination thereof.
Reference to Master Electromagnet Controller 24 also includes all software, data and processes necessary for its operations and, furthermore, encompasses the interfacing with any hardware and/or software component, element, unit or device external to AEG-Master Unit 20. AEG-Master Unit 20 also controls or influences, directly and/or indirectly, the operations of AEG-SU 22 and, more in general, the operations of AEG 2.
The terms "Master" and "Slave" in this application relate to elements in the Activity Environment Generator 2, whereby an element (the "Master") controls one or more of the other elements (the "Slave/s") according to predefined rules, including the case in which a AEG-Master Unit transfers or shares control over one or more elements with one or more AEG-Slave Unit/s.
An external object to which a AEG-Master Unit and/or or a AEG-Slave Unit is attached to, rather than being attached to the User 1 (or being otherwise held or carried by the User 1), is referred to as an "Activity Environment Generator Accessory" or, in short, "AEG-Accessory". The "AEG-Accessory" may be any surface, object, physical medium or accessory external to User 1 to which a AEG-Master Unit and/or or a AEG-Slave Unit is/are attached to.
The term "attached", in reference to the AEG 2 or in reference to any number of its elements, means any manner in which one or more of said AEG elements is/are carried or placed, worn—thus becoming an "AEG-Wearable", strapped, stuck, mounted, fastened, tied or otherwise secured to any part of a User's body—typically, but not exclusively, to one or more of: a limb, the neck, the head, fingers, toes, knee, elbow, the jaw. The term "body" In this application means each and all physical parts of a person.
The term "attached", in relation to the manner in which an AEG-Element is attached to an AEG-Accessory or to san AEG-Wearable, also includes the terms "integral to", "built-in", "welded", "glued", "sewed" or equivalent ones.
In the case of an AEG-Accessory, an AEG element may be attached, for example, to the back of an armchair, the arms of an armchair, a mat, floor, wall, a door, an airplane seat, a sport accessory, a strap, an elastic band, a handle and so forth.
In the case of an AEG-Wearable, an AEG element may be attached, for example, to a belt, a glove, a shoe, a shirt, a collar, a sport wearable, and elastic band, a head band, a helmet and so forth.
At 26 a Setpoint, that is, the desired value for a variable, is set by Master Electromagnet Controller 24. The variable may be, for, instance the pressure between Master Electromagnet 21 and Slave Magnet 23. If this is the case, the Setpoint defines the intensity and sign of the desired Force (attractive or repulsive) between Master E-magnet 21 and Slave Magnet 23 being said Force indicated as 200. User 1 carries desired activities by interacting with Force 200 and/or with communication and/or feedback provided by AEG 2.
The Setpoint may be constant and/or predefined or it may change dynamically according to a Training Variable (or, in short, "TR-V") 27, and/or a number or Training Variables present in Training Program/Data/Commands (or, in short, "TDC") 28 and, in general, according to commands issued by Magnet E-magnet controller 24.
TDC 28 may be of any kind including ones necessary for or deriving from the operation of the AEG 2 including commands that influence the operation elements of AEG 2.
TDC 28 also includes prestored data, software, protocols, streamed data, APP 209, databases, data and calculations results of any kind and resulting, stored, originated in or acquired from elements the AEG 2 or from elements external to it. TDC 28 or parts thereof may be transmitted between one or more of the elements of AEG 2. Said transmission may be bidirectional or one-directional according, to the requirements of specific embodiments of the invention.
TDC 28, or parts, thereof may be prestored in the AEG-Master Unit 20 and/or provided through Connectivity Unit 207 and/or HMI 29, being the latter two described below.
Examples of TR-V are: attractive or repulsive force (the magnetic force between Master E-magnet 21 and Slave Magnet 23) at a given point of time, duration and timing of said forces, the distance between AEG-MU 20 and AEG-SU 22, the spatial coordinates of the AEG-MU 20 and/or the AEG-SU 22, their relative displacements etc.
Force Transducer 201 transforms Force 200 from mechanical force into an electrical signal which constitutes Process Value (or in brief, "PV") indicated as 202. Force Transducer 201 may be of any suitable kind including, for example, a strain gauge or a piezoelectric sensor.
In 203 the difference between Setpoint 26 and Process Value 202 is continuously evaluated, resulting in the error signal ε(t)=SP−PV. The output current I(t) will be adjusted by the Master E-magnet controller 24 in a way that that seeks to annulate the error signal value using a predetermined function ("I=f(error)") 205 whereby error=ε(t).
For the sake of example, only, below is a well-known feedback control function where C1, C2 and
C3 are constants, "t" is the time and "ε" stands for error.I(t)=C1×ε(t)+C2×∫ε(t)dt+C3×dε(t)/dt
This is known as the PID controller standard standing for Proportional-Integral-Derivative controller.
The apparatus in FIG. 2 further includes a memory 206 that for both storing data and for running commands and executing any process required by specific embodiments of the invention. Memory 206 may be, for example a Flash memory, a combination of any of Ram, Rom, NV-Ram, integrated circuit, hardwired and so forth, as long as memory 206 satisfies all the requirements of a volatile and non-volatile memory. Memory 206 may be a single component or a number of separated components that that work in conjunction. Memory 206 may, among other things, be integral to Master E-magnet controller 24 or part of the same circuit.
Memory 206 stores and/or runs, among other things, all data, commands and processes required by the invention, including those of TDC 28 and those required by Master E-magnet controller 24.
AEG-MU 20 is preferably provided with Connectivity Unit 207 which enables the communication between AEG-Master Unit 20 and any device and/or hardware and/or software component, element or unit external to AEG-Master Unit 20. Connectivity Unit 207 may use any kind of wired connection, such as USB, or HDMI and/or may use any kind of wireless connection provided by Bluetooh, Wi-Fi, and/or any kind of wireless network including one or more of: a cellular network, LANS, WLAN, PAN, MAN, WAN, internet, TV network, satellite network etc.
A Communication Device 208, for instance a cellular phone, is connected to the AEG-MU 20 though Connectivity Unit 207.
Communication Device 208 is equipped with an Application (or, in short, "App") indicated as 209 and, optionally, with any other software and/or data, including, for example TDC 28 or parts thereof, which can be used by User 1, to control all the operations of the AEG-Master Unit 20, of AEG-SU 22 and, directly and/or indirectly, the operations of AEG 2.
A limited list of features of App 209 includes the following examples:
Receiving, through suitable interface, feedback related to an AEG-Session, which feedback belonging to one or more of the following kinds: textual, graphic, audio, haptic and so forth. Said feedback, may be originated from App 209 itself and/or from Trainer 212 and/or from Cloud 214.
Changing Setpoint 26
Altering the course of the activity—increasing or decreasing difficulty. Selecting a TR-V 27.
Operating Power Source 210.
Carrying out any standard log-in and/or administrative operation (not shown in FIG. 2). Communicating and exchanging data with the organization related to cloud 214. Receiving updates for TDC 28 including files installation, backup and removal.
It is stressed that—depending on specific embodiments of the invention—the software and/or the data present in and/or used (or usable) by any two or more among Communication Device 208, App 209, HMI 29, Big Data 213, Remote Trainer 212 and Cloud 214, may be partially or entirely shared and/or overlapping and/or duplicated and/or complementary and/or substitutive and/or equivalent.
Power Source 210, which may be of any suitable kind, sustains the operations of the AEG-MU 20, the AEG-SU 22 and of all the other elements of AEG 2.
Master E-magnet controller 24 is provided with an on/off/idle functionality (211) which enables to toggle the state of AEG-MU 20 to one of said three states in response to specific predefined event such as, for example, a specific command generated by Communication Device 208, a certain interaction between AEG-MU 20 and AEG-SU 22 or a command issued by Remote Trainer 212.
AEG-MU 20 is optionally provided with a Human-Machine Interface (or, in brief "HMI") indicated as 29 which may consist of peripheral hardware and/or software for input and/or for output, including for, for example, switches, keypads, touchscreens, voice-commands generators and displays equipped with appropriate graphical user interface. HMI 29, according to the specific embodiments, may be provided in addition or in place of Communication Device 208. If provided in place of Communication Device 208, then HMI 29 is equipped either with App 209, or with a software which includes all or parts of the functionalities of App 209 and is optionally provided with connectivity capability. In both cases, said software is provided in a version that can be run in whatever operating system of the HMI 29.
HMI 29 may also consist of a computing device relative peripheral hardware and/or software for input and/or for output.
HMI 29 works in conjunction with AEG-MU 20 in a manner that allows transmission and/or use of TDC 28.
Remote Trainer 212 may be, a professional such as a doctor or a physiotherapist or a nurse, a training companion or any other person, that assists, monitors or, otherwise, participates or is involved in AEG-Session and/or in connection with said AEG-Session, before and/or after the AEG-Session itself. The term "AEG-Session", in this context, means any activity which is carried out using AEG 2 and/or in connection with the use of AEG 2 and/or in connection with the processes and data related to said use.
Remote Trainer 212 may be equipped with a Communication Device 209 and APP 208 or with HMI 29 or an equivalent equipment. Using said equipment, Remote Trainer 212 can communicate with APP 209 and/or Big Data 213 and/or HMI 29 and is afforded a wide range of possibilities that include, among other things, the following ones:
To monitor the AEG-Session carried out by User 1 and receive feedback related to said AEG-Session.
To influence Control Loop 25;
To change Force 200 in intensity and/or direction; To change one or more Training Variables 27; To use any portion of TDC 28;
Communicate with User 1 by graphic and/or text and/or voice communication; Provide User 1 with feedback;
Receiving data and/or sending data related to the AEG-Session to and/or from Cloud 214.
Consequently, Remote Trainer 212 can control—given of course that she/he is provided with the necessary authorizations as set in AEG 2—varied aspects of the AEG-Session.
For example, according to the invention Remote Trainer 212 determine the intensity and direction of Force with which User 1 interacts in the course of the AEG-Session. Further, Remote Trainer 212 can choose from TDC 28 a specific training program which contains specific exercises to be carried out in the course of the AEG-Session. Additionally, if a plurality of AEG-MU 20, and/or AEG-SU 22, HMI 29, and more than a single User 1, are involved in a AEG-Session, Remote Trainer 212 can determine the operations for each of these and coordinate the operations of each of said elements.
Cloud 214 is a public, private or semi-private cloud network cloud.
Preferably, Cloud 214 is enabled with cloud-computing features and/or machine-learning capability.
Examples of Cloud 214 include, according specific embodiments of the invention, clouds associated to any public and/or a private organization such as a hospital, a university, a government organization, a health service which organizations hold information in form of Big Data 213. Unless otherwise stated, the term "Cloud" includes the term "Big Data".
Big Data 213 includes data of any of the above mentioned public and/or a private organization. Big Data 213 may be dynamically updated. Consequently, an AG-Session can be enhanced from dynamically accumulated data and help User 1 and/or Trainer 212 and/or AEG 2 directly, without the involvement of User 1 and/or Trainer 212.
For example, TDC 28 may be frequently updated following analyses from data received in the course of an AEG-Session and/or from other medical, clinical or different kind of data provided by an organization relative to which Big Data 213 is accumulated, update or, otherwise, accumulated.
Big Data 213 may also serve as a valuable source of information for medical, clinical, logistic, statistical and administrative purposes which allow the organization, to which Big Data 213 pertains, to better plan and administer services and treatments both on micro and macro scale and improve customer-service-supplier relationship by better individually targeted treatment and attention.
For instance, accumulated data received from AEG-Sessions may show that an activity, carried out by one or more User 1 over a course of time, has demonstrated positive results in relation to a specific User 1 or a plurality of Users 1. Conversely, Big Data 213 may indicate that changes are required and point to possible required modifications, for example, in TCD 28.
Thus, for instance, if one or more User 1 has/have carried out an activity designed to improve his/their balance, following reoccurring falls, by exercising his/her feet and toes, and accumulated data over a certain time span shows a reduction in the occurrence of falls, the activity which has been proven beneficial may be continued for the same one or more User 1 and may, also, be prescribed, preventively, to other persons with a medical profile similar to User 1, even is said persons have not suffered yet of any significant lack of balance or actual falls.
FIG. 3 Shows one of the many possible variations of the invention.
This variation involves interaction with pneumatic pressure between AEG-MU 20 and AEG-SU 23 instead of and interaction with magnetic force.
Pneumatic Actuator Controller 216 replaces Master E-magnet controller 24.
Pneumatic Actuator 217 replaces Master e-magnet 21 and Slave magnet 23.
Pneumatic Actuator 217 may have, among other things, lineal and/or rotatory capabilities.
Pneumatic Actuator 217, may be, for the sake of example only, a Mini Pneumatic Actuator (having a bore size as small as 5-10 mm.) connected to a Compressed Air Source 218 which is, optionally, connected to a Power Source 210.
Pneumatic Actuator 217, produces Pressure 219 which is transformed by Pressure Transducer 220 from mechanical force into an electrical signal which constitutes Process Value (or in brief, "PV") indicated as 202. In this variation of the invention, Setpoint 26 provided by Pneumatic Actuator Controller 216, is a pressure value.
The output air flow denoted as FL(t) will be adjusted using a predetermined function FL(t)=f(error) 205.
In this variation of the invention a sample feedback control function could beFL(t)=C1×ε(t)+C2×∫ε(t)dt+C3×dε(t)/dt
Where C1, C2 and C3 are constants and FL(t) is the air flow and "t" is the time and "ε" stands for the error.
Then, the computed air flow value is converted from an electrical signal into an air flow signal by Electric to Pressure Signal Converter 222, that regulates the air flow inside Pneumatic Actuator 217 thus adjusting the pressure generated by Compressed Air Generator 218 to the desired pressure into Pneumatic Actuator 217.
Similarly to what described in connection of FIG. 2, the Setpoint may be constant and/or predefined or it may change dynamically according to a Training Variable (or, in short, "TR-V") 27, and/or a number or Training Variables present in Training Program/Data/Commands (or, in short, "TDC") 28 and, in general, according to commands issued by Pneumatic Actuator Controller 216.
In according to this variation of the invention a physical connection, indicated as 221, must be provided between AEG-MU 20 and AEG-SU 22 in order to enable Pneumatic Actuator 218 to act on AEG-MU 20 and AEG-SU 22.
Apart from what described above, the remaining elements of the AEG 2 in FIG. 3 are the same as the elements of the AEG 2 in FIG. 2.
In addition to what described above, one or more kinds of sensors may optionally be provided in order to measure the distance and/or position and/or speed between AEG-MU 20 and AEG-SU 22.
This may be useful in order to accurately follow the activity of User 1 and, for instance, better determine the trajectory followed in the course of an activity, the number of repetition of a certain activity (for instance a movement of a part of the body) and so forth.
Alternatively and optionally, the distance between AEG-MU 20 and AEG-SU 22 be estimated and/or calculated in Loop 25 based on the resulting pattern of errors found in 203 considering, for instance, the error over a lapse of time, whereby a certain range of error values may be indicative of limited movements over said lapse of time.
Examples out of a wide range of sensors include, according to each specific embodiment: distance transducers, distance sensors, tilt sensors, ultrasonic sensors, position sensors, magnetic position switches, proximity sensors, mechanical switches, variable reluctance sensors etc.
Additional variations of the inventions may use different kinds of force generators, other than the electromagnetic or pneumatic ones described in relation to FIG. 1 to FIG. 3, as long as such force generators are suitable for AEG2.
Also, according to additional variations of the invention certain elements, as for example, Control Loop 25 and Force Transducer 201 of AEG 2, could, optionally, be implemented in analog form.
Before the description proceeds the following points should be stressed out:
The description above of FIG. 2 and FIG. 3 configurations of AEG 2 with a single AEG-MU 20 and a single AEG-SU 22. However, the invention allows the use of multiple AEG-MU 20 and/or of multiple AEG-SU 22 in an AEG 2 in any desired combination and configuration. Thus, according to different specific embodiments, an AEG may include a single AEG-MU 20 and several AEG-SU 22, an array of AEG-MU 20 and an array of AEG-SU 22 having the same number of elements in each array and so forth.
Furthermore, as it will be described in one of the preferred embodiments, the configuration of MG 1 may be easily modified making the invention easily scalable.
FIG. 4 shows schematically the method of the invention relative to the apparatus description in FIG. 2.
At step 40 the training program for the AEG-Session is selected in APP 209 or in the HMI 29 or by Remote Trainer 212. Big Data 213 is available.
At step 41 Transfer Training program and parameters to TP/D/C 28 takes optionally place via connectivity unit 207.
At step 42 or, optionally, before step 40, User 1 Places active body part into AEG-SU 22. At 43 User 1 starts the AEG-Session designed to train a body part using APP 209.
At 44 TP/D/C 28 Initiates the training program which can controlled by Remote Trainer 212 and which can be modified, at all times, according to changes in Big Data 213.
At 45 Training Variable 27 is set.
Master e-Magnet controller 24 Initiates Control Loop 25 at step 53
Set-point SP(TR-V) 26 is determined by Master e-magnet controller 24 at step 54
At step 48 Error(t)=SP(TR-V)-PV(t) 204, is computed at time "t".
At 55 Output current I(t)=f(Error(t)) 205, is computed at time "t".
Master e-magnet 21 Current is set to I=I(t) at step 56.
Time counter moves up at 51.
At step 58 Force 200 generated by the interaction between e-magnet 21 and slave magnet 23 is measured by Force Transducer 201 and converted into electrical signal PV 202.
FIG. 5 shows schematically the method of the invention relative to the apparatus description in FIG. 3.
At step 40 the training program for the AEG-Session is selected in APP 209 or in the HMI 29 or by Remote Trainer 212. Big Data 213 is available.
At step 41 Transfer Training program and parameters to TP/D/C 28 takes optionally place via connectivity unit 207.
At step 42 or, optionally, before step 40, User 1 Places active body part into AEG-SU 22.
At 43 User 1 starts the AEG-Session designed to train a body part using APP 209.
At 44 TP/D/C 28 Initiates the training program which can controlled by Remote Trainer 212 and which can be modified, at all times, according to changes in Big Data 213.
At 45 Training Variable 27 is set.
Pneumatic Actuator Controller 216 initiates Control Loop 25 at step 46.
Set-point SP(TR-V) 26 by is determined by Pneumatic Actuator Controller 216 at step 47.
At step 48 Error(t)=SP(TR-V)-PV(t) 204, is computed at time "t".
At 49 Output air-flow FL(t)=f(Error(t)) 205, is computed at time "t".
Electric to air-flow signal converter 222 Sets airflow to FL=FL(t) at step 50.
Time counter moves up at 51.
At step 52 Pressure 219 generated on the Pneumatic Actuator 217 is measured by Pressure Transducer 220 and converted into electrical signal PV 202.

Method and apparatus for an activity environment generator


An apparatus and method for encoding of a video picture is disclosed. The video picture has a plurality of pictures. The pictures each have a plurality of macroblocks. The macroblocks each have a plurality of sub-blocks. The apparatus comprising a first module configured to generate a transform coefficient C.sub.ij for each of the sub-blocks of the macroblock. The apparatus further comprises a second module configured to variably quantize the transform coefficient by a scaling factor Q.sub.p based on the complexity of the picture and any rate control requirements.

Due to the current interest in digital multimedia interactive programs, there has been extensive activity in the international standards bodies dealing with still picture and motion video compression. In particular, the Motion Picture Experts Group (MPEG), a group working under the sponsorship of the International Standards Organization, is rapidly converging towards a standard for the compression of digital motion video. One of the interesting features of this standard is that only the "decoding" algorithm syntax will be specified in detail. It will be thus possible to have different encoders, all of which produce bit streams compatible with the standard's syntax, and yet result in different levels of video quality. The MPEG video standard is fully described in ISO-IEC JTC1/SC2/WG11, MPEG 90/176 Rev. 2, Dec. 18, 1990. This reference is hereby incorporated in its entirety into this disclosure. The MPEG standards will be briefly discussed herein.
Generally, the MPEG video standard defines a layered architecture for compressing a video sequence. First, a sequence of video pictures is subdivided into disjoint Groups of Pictures (GOP). Each GOP is compressed independently of other GOPs to facilitate random access to any picture and also to limit the propagation of transmission errors.
Every picture in a GOP is subdivided into Macro-Blocks (MB). For a color picture, a MB is a collection of 16.times.16 luminance pixels and two 8.times.8 blocks of chrominance pixels. In MPEG, the two chrominance components are sampled at half the horizontal and vertical resolution of the luminance. As such, a MB completely describes a 16.times.16 color segment of a picture. In a MB, the 16.times.16 luminance pixels are further subdivided into four luminance blocks of 8.times.8 pixels.
MBs can be coded into two modes, namely: intra and predictive. In intramode, a MB is coded independently of pixel data in previous or future pictures. In predictive mode a MB is coded with reference to pixel data in either a previous (forward prediction), a future picture (backward prediction), or both (interpolative prediction). A prediction is formed by applying motion compensation techniques to the referenced pictures, and an MB error data is generated by subtracting the prediction from the original pixel data.
The MPEG standard requires that the first picture in a GOP be coded as an intrapicture. An intra picture is defined as having all of its MBs coded in the intramode. The remaining pictures of a GOP are then coded as either unidirectional predictive pictures (i.e., its MBs are coded in a mixture of intramode and forward prediction) or bidirectional predictive pictures (i.e., its MBs are coded in any of the MB coding modes).
The still or motion picture data in the form of MB's (represented by either the actual MB pixel data (intramode) or only the error data (predictive) to be compressed is then inputted to a first compression step. This first compression step is a transformation applied by a 2-dimensional 8.times.8 Discrete Cosine Transform (DCT) to each of the MB blocks.
After applying the DCT to the six blocks in a MB, MPEG suggests that the resulting transform coefficients undergoes a second compression step. This second compression step is a scaling and truncation step (referred to in the art as "quantization"). Each of the DCT coefficients are uniformly quantized with a matrix of quantization steps. MPEG specifies one of two reference matrices from which the quantization steps may be derived. The choice of which matrix depends on the MB mode. This second step is an additional compression step which is necessary to achieve adequate compression of the picture data. Although the reference matrices can be defined by the encoder at the beginning of a video sequence, they remain fixed afterwards. MPEG allows dynamic changes to the matrix of quantization steps, however, by allowing a scaling factor for the reference matrices; this scaling factor can be changed for every MB. MPEG, however, does not disclose an apparatus or method for determining and changing the scaling factor. Keeping this scaling factor constant may result in the unnecessary loss of picture quality during the compression mode.

Apparatus and method for motion video encoding employing an adaptive quantizer

International Business Machines Corporation


A method of tracking a user position using a crowd robot, a tag device, and a robot implementing the same are disclosed, and the robot includes a controller, which cumulatively stores position information of a tag device, generates a moving route corresponding to the stored position information of the tag device, and corrects the position information of the tag device based on position estimation information of a crowd robot around the tag device sent from the tag device.

In spaces where exchanges take place, such as supermarkets, department stores, airports, and golf courses, various people carry various objects. In this case, a device such as a cart may assist a user in movement of an object while moving following the user in order to provide user convenience.
In addition, a device adapted to provide certain information may provide information to a user while following the user in a large space.
In order to allow these robots to assist a user or to provide information, it is necessary for these robots to move following the user. To this end, the robots are required to ascertain a user position.
However, since there can be a problem of distortion of signals or measurement failure in the course of tracking a user position, there is a need for a technique for improving accuracy in tracking the user position by a robot.

Method of tracking user position using crowd robot, tag device, and robot implementing thereof


On a lower magnetic shield film, a lower gap film is formed on which a conductive lead film and a magnet film is laminated. The magnet film forms a bias permanent magnet film for generating a single magnetic domain of a magneto-resistance film. This lead film is trenched to the lower gap layer (20) to form a trapezoid trench and separated leads. A sensor unit having the magneto-resistance film is formed conformally to the trench and electrically connected to the separated leads. An upper gap is formed on the sensor unit (28), and an upper shield is formed on the upper gap.

a) Field of the Invention
The present invention relates to a magneto-resistance (MR) reading head used for hard disks or the like, adn more particularly to an MR reading head capable of reading data recorded on a narrow track at a high density, by suppressing the generation of a side-lobe which shows an off-track characteristic specific to an MR element, while preventing a sensitivity from being lowered.
b) Description of the Related Art
An MR head is a magnetic head dedicated to reproducing (reading) information recorded on a magnetic recording medium with an MR element by detecting a magnetic field generated from storage magnetic poles in the recording medium. As compared to an induction type magnetic head, an MR head has an advantage in improving a track density and a linear density of recording. Therefore, an induction-MR type composite magnetic head for hard disks is made of a combination of an MR head and, for example, a recording (writing) induction type head.
A conventional induction-MR type composite magnetic head for hard disks is shown in FIGS. 8A and 8B. FIG. 8A is a cross sectional view showing the side elevation of the composite magnetic head, and FIG. 8B is a perspective view thereof as seen from the recording medium plane side. The induction-MR type composite magnetic head 10 is constituted by a lamination of an MR type magnetic head (MR head) 12 and an induction type magnetic head 14 both being formed on a rear end portion of a substrate 16 having a slider surface 24. Both the heads 12 and 14 are manufactured by adopting thin film forming technique.
A lower shield layer 18 of the MR type magnetic head 12 is formed on the slider substrate 16 at its read end portion. The rear end portion of the slider substrate 16 is flat and the lower shield layer 18 is of a flat sheet structure. A lower gap layer 20 of non-magnetic material is laminated upon the lower shield layer 18. A sensor unit 28 is formed on the lower gap layer 20 with its end surface being directed toward a counter surface (slider surface) 24 of a recording medium. The sensor unit 28 is made of an MR film 46, a magnetic spacer layer 48, and a soft adjacent layer (SAL) 50 deposited in this order on the lower gap layer 20 and made flat. As shown in FIG. 8B, on the opposite end portions of the sensor unit 28, leads (lead conductors) 30 and 31 are laminated to establish electrical contacts to the sensor unit. The region of the MR film 46 not overlapped with the leads 30 and 31 is an active region whose resistance is changed by a magnetic field. The region of the MR film 46 overlapped with the leads 30 and 31 is an inactive region whose resistance change cannot be detected because of the high conductivity leads 30 and 31. An upper gap layer 32 of insulating material such as alumina is formed on the sensor unit 28 and leads 30 and 31. An upper shield layer 34 is formed on the upper gap layer 32. The lower and upper shield layers 18 and 34 are formed by depositing soft magnetic material having a high permeability through sputtering, vapor deposition, plating, or the like.
The induction type magnetic head 14 uses the upper shield layer 34 of the MR type magnetic head 12 as its lower core. Sequentially deposited on the upper shield layer 34 are a gap layer 36, a coil 37 buried in an insulating layer 38, an upper core 40, and a protection film 42. The gap layer 36 separates the upper and lower cores 40 and 34 at the lower end as shown in FIG. 7A to form a magnetic gap.
In recording data with the induction-MR type composite magnetic head 10 shown in FIGS. 8A and 8B, a recording current is flowed through the coil 37 of the induction type magnetic head 14 to generate a recording (leakage) magnetic field in the magnetic gap between the upper and lower cores 40 and 34 and record data in a recording medium by this magnetic field. In reproducing data, a predetermined current is flowed through the MR film 46 via the leads 30 and 31 of the MR type magnetic head 12 to magnetically saturate the SAL film 50 and apply a transverse bias magnetic field to the MR film 46 by this saturated magnetic field. A current flowing through the MR film 46 via the leads 30 and 31 is a sense current by which a voltage drop in the MR film 46 generated by a change in an applied magnetic field is detected. As the head 12 traces a track of the recording medium, a voltage across the MR film 46 is modulated by magnetization information on the track so that the recorded data can be detected.
The off-track characteristic of a magnetic head will be explained. FIG. 9A illustrates a read/write operation by a general induction type magnetic head. In a write operation, a signal is written on a track of a recording medium (hard disk) in a pole width Tw of the poles of the upper and lower cores 40 and 34. This written magnetization information is read by the induction type magnetic head. In this case, a maximum reproduction sensitivity is obtained when the poles reach the position just above the track width Tw. As the poles shift in a direction (track width direction) perpendicular to the motion direction of the recording medium, the reproduced output lowers in correspondence with a shift amount of the poles from the track width Tw. FIG. 9B illustrates the off-track characteristic O.sub.I. The abscissa represents a lateral shift from the track center, and the ordinate represents a reproduced output voltage in an absolute value. As shown in FIG. 9A, the lateral right shift of the poles is represented by a plus (+) sign, and the lateral left shift is represented by a minus (-) sign.
The off-track characteristic O.sub.I of a general induction type magnetic head shows a maximum sensitivity Vmax when the center of a track width of magnetization information written on a recording medium becomes coincident with the center of the pole width Tw. The reproduction sensitivity Vmax gradually lowers symmetrically with the right and left shifts of the poles, as the poles shift in the track width direction. A reproduction output of the induction magnetic head depends on a speed of the recording medium relative to the head, and is zero when the relative speed is zero.
For reproduction with the MR-induction type composite magnetic head, the MR type magnetic head is used. Since the MR type magnetic head detects a change in magnetic flux density as a change in resistance, it can detect magnetization information independently from a relative speed between the head and magnetic recording medium. FIG. 10 shows an example of the off-track characteristic of an MR type magnetic head. As shown, the off-track characteristic O.sub.MR is asymmetric with the track center and has a small bump called a side-lobe. The reason why this side-lobe is formed will be described with reference to FIGS. 11A to 11EA.
FIGS. 11A to 11E show relative positions of a track 52 written on a recording medium and a MR type magnetic head such as shown in FIGS. 8A and 8B. FIGS. 11AA to 11EA illustrate mechanisms of generating reproduction outputs by the MR type magnetic head at corresponding positions shown in FIGS. 11A to 11E. The relative positions of FIGS. 11A to 11E are shown as cross sections perpendicular to a plane of a recording medium.
An MR film 46 has an easy axis of magnetization in a horizontal direction or longitudinal direction as seen in FIGS. 11A to 11E. Of the MR film 46, the regions (inactive regions) overlapped with the leads 30 and 31 are called lead regions 46a and 46b, and the region between these lead regions is called an active region 46c. As magnetization in the active region 46c changes, a reproduction output changes. The width of the active region 46c is equal to the width of a track 52. It is assumed here that a sense current i flows through the MR film 46 from left to right and a magnetic field is generated upward in the MR film 46. It is also assumed that a magnetization vector of the track is upward.
Current flows through the MR film 46 to magnetically saturate the SAL bias film 50 (FIG. 8B) and this saturated magnetic field applies an upward bias magnetic field to the active region 46c. In order to obtain a maximum sensitivity, the magnetization direction is set about 45 degrees relative to the plane of a magnetic recording medium. Solid lines in the MR film 46 indicate magnetization in the MR film 46 without external magnetization, and broken lines indicate magnetization rotation in the MR film 46 caused by a magnetic field from the track 52.
In FIGS. 11AA to 11EA, a magnetization vector in the MR active region generated by a static bias is indicated by M1, a magnetization vector generated during a reproduction operation is indicated by M2, and the resultant vector is indicated by M3. Namely, the magnetization vector changes from M1 to M3 during the reproduction operation.
The plus (+) sign in the abscissa in FIG. 10 corresponds to a track left shift relative to the active region 46c, and the minus (-) sign corresponds to a track right shift. FIGS. 11A to 11E stand for two minus values, 0, and two plus values.
As shown in FIG. 11A, when the track 52 is at the minus position and under the lead region 46a, magnetization of the lead region 46a is influenced by a magnetic field of the track 52. Therefore, magnetization in the active region 46c receives a clockwise vector as shown in FIG. 11AA. The influence of this clockwise vector becomes larger, the higher the uniaxial anisotropy of the MR film 46.
As shown in FIG. 11B, when the track 52 moves right and rides over the lead region 46a and active region 46c, the magnetic field of the track 52 directly influences the magnetization of the active region 46c and further gives a clockwise vector to the active region 46c as shown in FIG. 11BA. Therefore, a reproduction output further increases.
As shown in FIG. 11C, as the track 52 further moves right to the position coincident with the active region 46c, the direct influence of the track 52 upon the active region 46c becomes maximum. At this time, the influence of the clockwise magnetization vector is strongest and the output is maximum.
As shown in FIG. 11D, as the track 52 further moves right from the track center and rides over the active region 46c and lead region 46b, the magnetic field of the track 52 influences the lead region 46b to rotate the magnetization of the active region in a counter-clockwise direction. Therefore, as shown in FIG. 11DA, the function of clockwise rotation of the magnetization in the active region is cancelled and the reproduction output rapidly lowers. The reproduction output becomes zero when the clockwise magnetization vector in the active region 46c directly influenced by the magnetic field of the track 52 balances just with the counter-clockwise magnetization vector in the active region 46c influenced by the magnetization in the lead region 46b caused by the magnetic field of the track 52.
As shown in FIG. 11E, as the track 52 further moves right and reaches under the right lead region 46c, The magnetic field of the track 52 influences the magnetization in the lead region 46b, and the magnetization in the active region 46c is rotated in the counter-clockwise direction. Therefore, as shown in FIG. 11EA, the magnetization vector is rotated in the counter-clockwise direction and a reproduction output of an opposite phase is generated. This opposite phase output gradually reduces as the track 52 further moves right away from the lead region 46b.
From the above reason, the off-track characteristic becomes asymmetrical as shown in FIG. 10. The narrower the width (track width) of the active region 46c is set, the larger the side lobe SL. If the direction of current is reversed, this relation is also inverted and the side-lobe SL appears on the left side. Such a side-lobe becomes a vital obstacle against a reliable tracking servo and makes it impossible to perform a servo control of a narrow track. High density recording is therefore hindered.
As a method of reducing a side-lobe, it can be considered that magnetization (in the same direction of an anisotropic magnetic field in the MR film 46) of uniaxial anisotropy bias magnet films on the right and left sides of the MR film 46 is made stronger. However, in this case, in order to maintain the direction of magnetization in the MR film 46 at 45.degree., a bias magnetic field of the SAL bias film 50 is required to be made stronger. Therefore, a change in the direction of magnetization in the MR film 46 with the magnetic field from a recording medium becomes small and the reproduction sensitivity lowers. This is conspicuous particularly for narrow tracks.
There is proposed a method of manufacturing magnetic head utilizing a tapered surface.
On a flat non-magnetic substrate, a tri-layer which comprises a longitudinal bias layer, a non-magnetic spacer layer, and a magnetoresistive layer, is formed. A resist film is coated on the tri-layer and patterned. Here, the cross sectional shape of the resist pattern is arranged to have a lower hollow or recess. The tri-layer is subjected to ion milling using the resist pattern as a mask, while changing the angle of the substrate relative to the ion beam in the ion milling chamber. The ion milling may be performed using Ar.sup.+ ions. The cross section of the resulting tri-layer diverges downwardly. Namely, the cross section has a trapezoital shape.
A hard magnetic bias layer and an electrode layer are laminated on the tri-layer using the resist pattern as a mask. The hard magnetic bias layer abuts against the tapered side surface of the magnetoresistive layer. Then, the substrate is immersed in chemical agent to remove the resist pattern. Here, the hard magnetic bias layer and the electrode layer deposited on the resist pattern are also removed (i.e. lifted off).

Magneto-resistive reading head with two slanted longitudinal bias films and two slanted leads


An inverter device has a three-phase inverter for converting DC electric power into AC power for supplement to an AC electric motor and a control device operatively associated therewith, and the control device includes a phase current detection section for outputting a phase current waveform based on a DC input current and an operational processor section for performing operational processing for control of said inverter device based on the phase current waveform. Thereby, the inverter device can be constructed to be very compact.

The present invention relates to control devices of inverters for variable-speed control of alternating current (AC) electric motors.
Prior known methods for controlling an inverter of the type that is used for variable-speed drive of induction motors typically include a V/f-constant control technique for controlling an output voltage V1 of the inverter in a way proportional to a primary frequency f1 thereof. With this approach, while it is possible to permit the excitation current of an induction motor to stay substantially constant, application of a load can lead to an increase in voltage potential drop due to the electric motor""s primary resistance r1, resulting in a decrease in induced electromotive force of such motor. This would disadvantageously result in a decrease in magnetic flux of the motor, causing the motor""s output torque to decrease accordingly. Another problem is that the xe2x80x9crealxe2x80x9d velocity tends to decrease with respect to a velocity command, resulting in an increase in velocity variability ratios. One approach proposed to avoid these problems is to employ automatic torque boost control techniques for achievement of torque increase in middle and low velocity regions, in particular.
A typical known approach is to detect an electric motor current by use of separate current detectors corresponding in number to two phases, as provided on the inverter output side; then convert in magnetic flux phases this current from stator coordinates into rotating magnetic field coordinates (uvw/dq conversion) to obtain a torque current Iq; then determine through computation a primary resistance voltage drop component r1xc2x7Iq in accordance with the current obtained; and, thereafter, calculate a voltage command Vm through addition of it to a V/f-constant voltage (induced electromotive force). In this case, the voltage command is Vm=Kxc2x7f1*+r1xc2x7Iq. Here, K is the proportional gain. Such control for permitting an output voltage value to increase with an increase in current in this way is called xe2x80x9cautomatic torque boost control.xe2x80x9d Further, a slip frequency fs in proportion to the torque current can be added to a reference frequency f0* to thereby compute an inverter output frequency command f1*. In this case, f1*=f0*+Ksxc2x7Iq. This control is known as slip compensation among those skilled in the art. These schemes suffer from a cost increase due to the fact that two separate current detectors for independent detection of two phases are required on the inverter output side. On the other hand, another scheme is also available for computing the torque current equivalent components from the average value Idc of inverter DC input currents and then performing the torque boost in accordance therewith. This control method constitutes a scheme for detecting Idc to compute an effective power current Iqx approximating the torque current Iq for compensation of the inverter output voltage in accordance with the significance of this current, in view of the fact that Equation 1 is established due to the equality of power on the DC side of the inverter to that on the AC side thereof.                     "AutoLeftMatch"                                                                              Vdc                  ·                  Idc                                =                                  3                                                        xe2x80x83                                                                          V1                    ·                    I1                    ·                    cos                                                                          xe2x80x83                                                      ϕ                                                                                =                                  3                                                        V1                    ·                    Iqx                                                                                (        1        )
Here in the Equation 1, Vdc is the DC voltage of an inverter, Idc is the DC current average value, V1 represents the significance of an inverter output voltage (phase voltage), I1 represents the significance of an electric motor current, and cosxcfx86 is the power factor. However, in AC electric motors, such as induction motors, the output voltage V1 is to be controlled in a way substantially proportional to the inverter frequency in order to control the value of V/f so that it remains constant. Due to this, V1 decreases in low speed regions, resulting in a noticeable decrease in Idc, as apparent from Equation 1 above. Accordingly, the effective power equivalent current Iqx decreases in detection accuracy, which disadvantageously poses a problem in that the automatic torque boost control decreases in accuracy.
Alternatively, current limit control is designed to detect three phase components of an inverter output current; and, when a current value goes beyond a pre-specified current limit level even with respect to one phase thereof, the inverter output frequency is reduced to thereby lower the slip frequency of an induction electric motor for causing the motor current to stay below the limit level, thus preventing occurrence of unwanted over-current trip phenomena. In this case, at least two motor current sensors are required.
Due to this, several schemes for computation and detection of the inverter""s output current from a DC input current(s) of the inverter to satisfy electric motor sensorless design requirements have been proposed to date, such as for example those as disclosed in Japanese Patent Laid-open Nos. 8-19263 and 6-153526, and IEE Proceedings Vol. 136, No. 4, Jul. 1989 Pages 196-204. Also, some important teachings as to the relation among the inverter""s DC input current and output current plus gate states have been recited in Journal xe2x80x9cDxe2x80x9d of the Institute of Electrical Engineers of Japan, xe2x80x9cSmoothing Capacitor""s Capacitance Reduction and Rapid Stop/Restartup Control Method for Voltage-Type PWM Converters,xe2x80x9d (Apr. 1, 1992) at page 33.
In these electric motor current sensorless techniques, as recited in the above-identified Japanese documents, the one described in Japanese Patent Laid-open No. 8-19263 is designed to sample-hold a DC current in all the gate states once at a time whenever a gate state changes, resulting in an output of a sample-hold circuit varying whenever the gate state changes. Further, a difference (DC current change component) between two sample-hold circuit output values is computed in units of gate states, which requires the use of xe2x80x9cspecialxe2x80x9d A/D converters and microcomputers of the type which may offer high-speed operabilities. As for the technique of Japanese Patent Laid-open No. 6-153526, this Japanese document is completely silent about any practical configuration including the arrangement of sample-hold circuitry and how to make sample-hold signals required. Additionally, the Japanese Patent Laid-open No. 6-153526 teaches inverter output current detection methodology; however, it fails to teach current limit control and automatic torque boost control methods.
The present invention has been made in view of the above problems and its object is to provide a control device for use with an inverter operable to detect from the inverter""s DC input current the amplitude of an electric motor current along with a torque current and/or excitation current thereof, and then using them to perform current limit control, automatic torque boost control, or velocity sensorless vector control and the like.
An inverter device in accordance with the present invention comprises a three-phase inverter which converts DC electric power into AC power as a supplement to an AC electric motor, and a control device operatively associated therewith. The control device includes a phase current detection section for outputting a phase current waveform based on a DC input current, and an arithmetic or operational processing section based on the phase current waveform for performing operational processing tasks for control of the inverter device.
According to the present invention, since a three-phase AC phase current is detected on the basis of the DC input current, it will no longer be necessary to provide a current detector for each phase. Owing to this, the inverter device may be reduced in size or lowered in cost. Further, since the inverter is controlled based on the phase current waveform, it is possible to adequately control the inverter without having to speed up the operational processor unit.
A control device of another inverter device also incorporating the principles of the instant invention is arranged to include sample-hold signal creation means for selecting in units of specified phase periods of inverter output voltage phasesxe2x80x94for example, 60- or 120-degree phase periodsxe2x80x94one gate state from among gate states for causing a positive side arm switching element or a negative side arm switching element of a three-phase inverter to turn on only within a time period corresponding to one phase of three phases thereof, and also from gate states for causing it turn on within periods corresponding to two phases (six kinds of gate states in total since each consists of three kinds), and a sample-hold circuit for sample-holding an inverter DC input current in the one gate state as selected. Whereby, an output of the sample-hold circuit is rendered variable continuously in a way synchronous with the electric motor current within a time period corresponding to the specified phase of the inverter output voltage phases.
A control device of another inverter device in accordance with this invention includes a first sample-hold circuit for sample-holding a DC input current of an inverter in a gate state that causes a positive side arm switching element or negative side arm switching element of a three-phase inverter to turn on within a period corresponding to only one phase while letting it turn off within periods corresponding to the remaining two phases thereof, and a second sample-hold circuit for sample-holding a DC input current in a gate state that causes it turn on within periods corresponding to two phases while turning it off within a period corresponding to the remaining one phase thereof. With such an arrangement also, an output of the sample-hold circuit is made variable continuously in synchronism with the electric motor current within the time period equivalent to the specified phase period of the inverter output voltage phases.
For the purposes of current limit control, the control device of the inverter device in accordance with the present invention is further arranged to reduce the inverter""s output frequency when any one of the output values of the first and second sample-hold circuits goes beyond the preset level. Whereby, the resultant slip frequency of an induction electric motor decreases, thus making it possible to achieve the intended current limit at high speeds.
For the torque boost control, the control device of the inverter device in the present invention is further arranged to provide means for calculating a torque current and/or excitation current of an AC electric motor on the basis of a reference phase with an inverter output frequency command integrated and the first and second sample-hold circuit output values, and means for varying an output frequency or output voltage of the inverter in accordance with a calculated value. Whereby, it is possible to achieve the intended torque increase (automatic torque boost control) by letting the inverter output voltage increase with an increase in torque-component current upon increasing of the load. Furthermore, it is possible to reduce the deviation of a real speed or velocity with respect to a velocity command due to slip compensation for allowing the inverter output frequency to increase with an increase in torque current.


An A/D converter system includes a first A/D converter with calibration circuitry. Also included in the system is an auxiliary A/D converter having a lower performance level than the first A/D converter. Circuitry is provided for temporarily switching an A/D conversion from the first A/D converter to the auxiliary A/D converter during short time intervals used for calibration of the first A/D converter. The rate at which the A/D conversion is switched is lower than the sampling rate of the first A/D converter.

The present invention relates to A/D converters (analog-to-digital converters), and in particular how to enable background calibration of such converters.
The maximum achievable accuracy-speed performance of any A/D-converter is limited by non-ideal effects associated with its building blocks. Typically, the performance is limited by settling time, finite amplifier gain and/or analog component mismatch. When designing high-speed, high-accuracy A/D converters, these limitations impose very stringent demands on the building blocks, leading to prolonged design time. They also require the use of manufacturing processes that are optimized for component matching and performance, thus increasing the manufacturing cost.
Many non-ideal effects can be compensated for by using calibration. The problem is that the efficiency of the calibration may be degraded by drift and ageing. Therefore it is desirable to be able to continuously calibrate the A/D converter during normal operation.
One of the more popular approaches to background calibration is to use the xe2x80x9cskip-and-fillxe2x80x9d approach [1]-[2]. During normal operation, every kth sample is skipped, and the hardware is reconfigured to perform a calibration operation. The gap representing the skipped sample is filled by interpolation by using a number of adjacent samples. The problem with these solutions is that interpolation can only predict the skipped sample accurately when the input signal has a limited bandwidth. If the input signal is completely random, or if it can have any frequency over the entire Nyquist bandwidth, any guess is as good as the interpolated value. In the implementation described in [2], the performance is seen to degrade significantly for input frequencies above ⅔ of the Nyquist frequency (fs/2). So, even with as much as 44 taps interpolation (22 samples before, and 22 samples after the gap), it is not possible to accurately track more than ⅔ of the Nyquist bandwidth. This is in accordance with the theory described in [1]. Such a high-order interpolation requires a significant amount of digital hardware, and a long output delay (latency).
Another method to create a calibration time-slot is found in [3], where an input sample queue is formed by a cascade of sample-and-hold circuits. By emptying the queue slightly faster than it is filled, a calibration time-slot is occasionally available. The drawback with the xe2x80x9cinput-queuexe2x80x9d method is that each extra sample-and-hold stage adds distortion and noise. Therefore this approach is not optimal for high-speed, high-resolution A/D converters.
A background calibration approach applicable to pipelined A/D converters is proposed in [4]. The principle is to temporarily remove the pipeline stage to be calibrated from the signal path, and replace it with a substitute extra pipeline stage. Calibration of the disconnected pipeline-stage is then performed outside the pipeline. This xe2x80x9chardware-substitutionxe2x80x9d method is limited in several ways:
1. Its application is limited to pipeline A/D converters, or at least to A/D converter architectures having a cascade of identical stages.
2. The calibration is done outside of the conversion signal path, which means that the stage under calibration is not seeing the same environment as during normal operation. This may lead to incomplete calibration.
3. The conversion signal path is always filled with conversion samples. Thus it is not possible to insert a calibration value in the pipeline, or switch the pipeline to calibration mode. This effectively rules out the use of a large range of high-performance digital calibration schemes, such as the ones described in [5]-[6].
Another class of A/D converters is described in [7]. These A/D converters use several identical low sample rate A/D conversion units in parallel to build a high sample rate A/D converter. The units sample the analog signal in a cyclical manner. Calibration of one unit may be performed when another unit is sampling. Thus, no interpolation is necessary. However, this type of parallel converter is also very complex and expensive.
An object of the present invention is to enable the use of a wide range of calibration methods, without the inherent signal-bandwidth limitations imposed by the interpolation used in prior-art xe2x80x9cskip-and-fillxe2x80x9d methods and at a lower cost than the parallel A/D converter solution.
This object is achieved in accordance with the attached claims.
Briefly, the present invention provides a low performance auxiliary A/D converter that occasionally replaces the regular A/D converter for calibration purposes. Here the term xe2x80x9clow performancexe2x80x9d means lower performance than the regular A/D converter. The fact that the auxiliary A/D converter only has to be used occasionally (low sampling rate) means that the requirements on the auxiliary A/D converter are lower. Thus, parameters such as bit resolution and settling/conversion time are less critical.


The present invention is a system for detecting, tracking and recognizing human faces in a visual prosthesis. In a visual prosthesis, the input camera is always higher resolution than the electrode array providing percepts to the subject. It is advantageous to detect, track and recognize human faces. Then information can be provided to the subject by highlighting the face in the visual scene, providing auditor or vibratory notice that a human face is in the visual scene, looking up the face in a database to state the name of the person in the visual scene, otherwise communication id like providing a custom vibratory pattern corresponding to known individuals (like custom ring tones associated with caller ID) or automatically zooming in on a face to aid the subject in identifying the face.

In 1755 LeRoy first created a visual perception through electrical stimulation. Ever since, there has been a fascination with electrically elicited visual perception. The general concept of electrical stimulation of retinal cells to produce these flashes of light or phosphenes has been known for quite some time. Based on these general principles, some early attempts at devising a prosthesis for aiding the visually impaired have included attaching electrodes to the head or eyelids of patients. While some of these early attempts met with some limited success, these early prosthetic devices were large, bulky and could not produce adequate simulated vision to truly aid the visually impaired.
In the early 1930's, Foerster investigated the effect of electrically stimulating the exposed occipital pole of one cerebral hemisphere. He found that, when a point at the extreme occipital pole was stimulated, the patient perceived a small spot of light directly in front and motionless (a phosphene). Subsequently, Brindley and Lewin (1968) thoroughly studied electrical stimulation of the human occipital (visual) cortex. By varying the stimulation parameters, these investigators described in detail the location of the phosphenes produced relative to the specific region of the occipital cortex stimulated. These experiments demonstrated: (1) the consistent shape and position of phosphenes; (2) that increased stimulation pulse duration made phosphenes brighter; and (3) that there was no detectable interaction between neighboring electrodes which were as close as 2.4 mm apart.
As intraocular surgical techniques have advanced, it has become possible to apply stimulation on small groups and even on individual retinal cells to generate focused phosphenes through devices implanted within the eye itself. This has sparked renewed interest in developing methods and apparati to aid the visually impaired. Specifically, great effort has been expended in the area of intraocular visual prosthesis devices in an effort to restore vision in cases where blindness is caused by photoreceptor degenerative retinal diseases; such as retinitis pigmentosa and age related macular degeneration which affect millions of people worldwide.
Neural tissue can be artificially stimulated and activated by prosthetic devices that pass pulses of electrical current through electrodes on such a device. The passage of current causes changes in electrical potentials across visual neuronal membranes, which can initiate visual neuron action potentials, which are the means of information transfer in the nervous system.
Based on this mechanism, it is possible to input information into the nervous system by coding the sensory information as a sequence of electrical pulses which are relayed to the nervous system via the prosthetic device. In this way, it is possible to provide artificial sensations including vision.
One typical application of neural tissue stimulation is in the rehabilitation of the blind. Some forms of blindness involve selective loss of the light sensitive transducers of the retina. Other retinal neurons remain viable, however, and may be activated in the manner described above by placement of a prosthetic electrode device on the inner (toward the vitreous) retinal surface (epiretinal). This placement must be mechanically stable, minimize the distance between the device electrodes and the visual neurons, control the electronic field distribution and avoid undue compression of the visual neurons.
In 1986, Bullara (U.S. Pat. No. 4,573,481) patented an electrode assembly for surgical implantation on a nerve. The matrix was silicone with embedded iridium electrodes. The assembly fit around a nerve to stimulate it.
Dawson and Radtke stimulated cat's retina by direct electrical stimulation of the retinal ganglion cell layer. These experimenters placed nine and then fourteen electrodes upon the inner retinal layer (i.e., primarily the ganglion cell layer) of two cats. Their experiments suggested that electrical stimulation of the retina with 30 to 100 μA current resulted in visual cortical responses. These experiments were carried out with needle-shaped electrodes that penetrated the surface of the retina (see also U.S. Pat. No. 4,628,933 to Michelson).
The Michelson '933 apparatus includes an array of photosensitive devices on its surface that are connected to a plurality of electrodes positioned on the opposite surface of the device to stimulate the retina. These electrodes are disposed to form an array similar to a "bed of nails" having conductors which impinge directly on the retina to stimulate the retinal cells. U.S. Pat. No. 4,837,049 to Byers describes spike electrodes for neural stimulation. Each spike electrode pierces neural tissue for better electrical contact. U.S. Pat. No. 5,215,088 to Norman describes an array of spike electrodes for cortical stimulation. Each spike pierces cortical tissue for better electrical contact.
The art of implanting an intraocular prosthetic device to electrically stimulate the retina was advanced with the introduction of retinal tacks in retinal surgery. De Juan, et al. at Duke University Eye Center inserted retinal tacks into retinas in an effort to reattach retinas that had detached from the underlying choroid, which is the source of blood supply for the outer retina and thus the photoreceptors. See, e.g., E. de Juan, et al., 99 Am. J. Ophthalmol. 272 (1985). These retinal tacks have proved to be biocompatible and remain embedded in the retina, and choroid/sclera, effectively pinning the retina against the choroid and the posterior aspects of the globe. Retinal tacks are one way to attach a retinal electrode array to the retina. U.S. Pat. No. 5,109,844 to de Juan describes a flat electrode array placed against the retina for visual stimulation. U.S. Pat. No. 5,935,155 to Humayun describes a retinal prosthesis for use with the flat retinal array described in de Juan.
Each person's response to neural stimulation differs. In the case of retinal stimulation, a person's response varies from one region of the retina to another. In general, the retina is more sensitive closer to the fovea. Any stimulation, less than the threshold of perception, is ineffective. Stimulation beyond a maximum level will be painful and possibly dangerous to the patient. It is therefore, important to map any video image to a range between the minimum and maximum for each individual electrode. With a simple visual prosthesis, it is possible to adjust the stimulation manually by stimulating and questioning the patient. As resolution increases, it is tedious or impossible to adjust each electrode by stimulating and eliciting a patient response.
A manual method of fitting or adjusting the stimulation levels of an auditory prosthesis is described in U.S. Pat. No. 4,577,642, Hochmair et al. Hochmair adjusts the auditory prosthesis by having a user compare a received signal with a visual representation of that signal.
A more automated system of adjusting an auditory prosthesis using middle ear reflex and evoked potentials is described in U.S. Pat. No. 6,157,861, Faltys et al. An alternate method of adjusting an auditory prosthesis using the stapedius muscle is described in U.S. Pat. No. 6,205,360, Carter et al. A third alternative using myogenic evoked response is disclosed in U.S. Pat. No. 6,415,185, Maltan.
U.S. Pat. No. 6,208,894, Schulman describes a network of neural stimulators and recorders implanted throughout the body communicating wirelessly with a central control unit. U.S. Pat. No. 6,522,928, Whitehurst, describes an improvement on the system described in Schulman using function electro stimulation also know as adaptive delta modulation to communicate between the implanted devices and the central control unit.
Even with all of those technical improvements, it is difficult or impossible for a subject using a visual prosthesis to detect track and recognize faces. This often causes social difficulties as the blind subject cannot look directly at the person as they interact or interpret common facial features and head movements which aid in communication.

Face detection, tracking, and recognition for a visual prosthesis


An air conditioner for railway vehicles controlled in accordance with the air temperature in the car and data on at least one selected from the group consisting of underfoot temperature, radiant heat, air flow, humidity, outside air temperature, number of passengers and door opening operation. In this way, environment conditions which momentarily change are detected so as to prevent excessive cooling or heating in the car.

1. Field of the Invention
The present invention relates to the control of an air conditioner for railway vehicles for maintaining an optimum temperature within the vehicles.
2. Description of the Related Art
Examples of air-cooling railway vehicles using conventional air conditioners will be explained with reference to FIG. 64 schematically showing a train car, the circuit diagrams in FIGS. 65 and 67, the flowcharts of the controlling operation in FIGS. 66 and 68, and FIGS. 69 to 71 schematically showing the concepts of the controlling operation.
FIG. 64 is a schematic view of the structure of a train car equipped with a conventional air conditioner and the flow of data therewithin. This is similar to the structure of a train car equipped with an air conditioner and the flow of data therewithin described in Japanese Utility Model Laid-Open No. Hei 2-41037. In FIG. 64, the reference numeral 1 denotes a train car, 2 an air conditioner mounted on the upper part of the train car 1, 3 a heating/cooling power controller for controlling the heating/cooling power by varying the power of a compressor provided in the air conditioner 2, 4 an air conditioner control unit having a means for determining the heating/cooling power, 5 a control switch portion by which a train operator selects the heating or cooling operation, ON or OFF and sets the target temperature in the car, 6 a temperature detector which is composed of a thermistor or the like so as to detect the temperature of the air returned from the car, 7 a heated/cooled air supply opening and 8 a suction opening for sucking the air from the car.
FIG. 65 is a circuit diagram of the air conditioner 4. The air conditioner 4 is composed of an input circuit 41, a CPU 42, a memory 43 and an output circuit 44. An output from the control switch portion 5 in the train operator's compartment and an output from the temperature detector 6 are input to the input circuit 41. The heating/cooling power controller 3 controls the power of the compressor in accordance with the output of the output circuit 44. The CPU 42 calculates the optimum heating/cooling power, and the result of the calculation is supplied to the output circuit 44.
The operation of the air conditioner 4 will now be explained with reference to FIG. 66. A conventional air cooling device of this type controls the air temperature so as to be the target temperature or in the vicinity thereof while calculating the optimum cooling power from the difference between the temperature of the air to be controlled and the target temperature. This control method is generally called proportional control.
The proportional control method will be explained in the following with reference to the flowchart in FIG. 66. At step F1, the air conditioner 4 of the train is first turned ON by a train operator, and the target temperature T0 is set at step F2. At step F3, a preset time for measuring the temperature is allowed to pass, and the air temperature Tn in the car is detected at step F4. The temperature difference dT between the target temperature T0 and the air temperature Ta in the car is obtained at step F5. At step F6, the optimum cooling power is newly calculated from the temperature difference dT, in accordance with the cooling power chart shown in FIG. 69. When the optimum cooling power is obtained in this way, the cooling power for the current cooling operation is changed at step F7, and the cooling operation is continued at the newly changed cooling power at step F8.
In such proportional control, however, since the cooling operation is conducted at the cooling power determined by the temperature difference between the temperature of the air to be controlled and the target temperature, it is difficult to reach the target temperature depending upon the condition of the load, as shown in FIG. 70 which shows the concept of the controlling operation. For example, even if the cooling power is reduced, the air temperature in the car is sometimes lowered to a temperature lower than the target temperature after the time t1.
To solve this problem, PID control is disclosed in Japanese Utility Model Laid-Open No. Hei 2-41037. In PID control, not only is the temperature difference between the temperature of the air to be controlled and the target temperature detected, but also the precedent temperature difference is stored, and the optimum cooling power is calculated from the detected temperature difference and the precedent temperature difference. Therefore, the air temperature in the car does not remain at a different temperature from the target temperature for a long time but is easily controlled to be the target temperature. However, the air temperature in the car is susceptible to a change in the load such as the outside air temperature and the number of passengers, and it is difficult to follow the change in the load which occurs in a short time such as the increase in the amount of ventilating air due to the opening and closing of the doors and the passengers getting on and off. In addition, PID control is disadvantageous in that the calculation is complicated and in that a large memory capacity is required.
In the control method shown by the circuit diagram in FIG. 67 and the flowchart shown in FIG. 68, a fuzzy theory is applied to the control of the air conditioner so as to enable simple control and the attainment of the target temperature. The electric circuit shown in FIG. 67 has a region 431 of the memory 43 for storing a previously measured temperature difference dT.
This control method will be explained with reference to the flowchart in FIG. 68. The air conditioner of the train is first turned on by a train operator or the like at step F11, and the target temperature is set at step F12. At step F13, a preset time for measuring the temperature is allowed to pass, and the air temperature in the car is detected at step F14. The temperature difference dT between the target temperature and the air temperature in the car is obtained at step F15. At step F16, judgement is made as to whether or not the current measurement is a first measurement. If this is a first measurement, this temperature difference is stored in the memory 43 as a precedent temperature difference dTs. On the other hand, if this is a second or later measurement, the variance St of temperature difference with time, which is the difference between the precedent temperature difference dTs and the current temperature difference dT, is obtained at step F17. It is possible to determine whether the temperature in the car is stable or has changed in a short time from the variance of temperature difference with time. At step F18, the optimum cooling power is calculated by applying the fuzzy theory. FIG. 71 shows the image of the fuzzy rule. As shown in FIG. 71, the optimum cooling power for making the temperature in the car equal to the target temperature is inferred from the temperature difference dT between the air temperature in the car and the target temperature, and the variance St of temperature difference with time. For example, if the temperature in the car is lower than both the target temperature and the previously measured temperature, it is judged that the air-cooling is excessive, and the cooling power is reduced. On the other hand, if the temperature in the car is higher than both the target temperature and the previously measured temperature, it is judged that the air-cooling is insufficient, and the cooling power is increased. If there is no temperature difference between the air temperature in the car and the target temperature and there is no difference in the current temperature change and the precedent temperature change, it is judged that the air temperature in the car is being maintained in a good state and the cooling power is maintained as it is. When a correction value for the cooling power is obtained in this way, the cooling power for the current cooling operation is corrected by the correction value at step F18, and the cooling operation is continued at the newly changed cooling power at step F20. The temperature difference dT between the target temperature and the air temperature in the car is stored in the memory 43 as a precedent temperature difference dTs, and there is then a pause until the next temperature detection takes place.
Since the cooling operation is conducted while determining the correction value in accordance with the temperature in the car and the temperature change in this way, the temperature in the car is never maintained at a different temperature from the target temperature for very long and it is possible to follow well the change in the load. In addition, since the amount of data stored in the memory 43 need only be a precedent temperature difference, it is possible to control the cooling power relatively simply.
As explained in the related art, in a conventional air conditioner, the heating/cooling operation is conducted while changing the heating/cooling power to the optimum value using the correction value inferred from the temperature difference between the temperature in the car and the target temperature and the variance of temperature difference with time in accordance with the fuzzy rule so that the temperature in the car is constantly comfortable for the passengers. One of the important factors to be taken into consideration in determining the heating/cooling power is the load of the heating/cooling system. The load of the heating/cooling system thermally influences the space being heated or cooled. It is, for example, the outside air temperature which influences the air temperature in the car due to ventilation or by heat transferred from the wall, and passengers who evolve heat in the car. In the case of railway vehicles which run a long distance, the outside air temperature changes momentarily. In the case of subways, the platforms of some stations are air-conditioned, and the outside air temperature is different when traveling through tunnels than while stopping at stations. Since the railway vehicles have a number of large windows, the influence of solar radiation through the windows is large in all vehicles except subway trains, and its influence changes greatly according to the direction of travel and when vehicles run through tunnels. In addition, a great many passengers get off and on every time a train reaches a station, and sometimes, a car is heavily crowded in a certain section while there are few passengers in other next sections.
Since the heat evolved by the passengers greatly influences the heating/cooling operation, if the number of passengers is rapidly reduced, the temperature in the car is lowered, while if the number of passengers is rapidly increased, the temperature in the car is raised, Simultaneously with passengers getting off and on, a large amount of air ventilates, and the air temperature in the car changes due to the influence of the outside air temperature. It can be said that a typical characteristic of the air-conditioning in railway vehicles is that the load constantly changes in this way. When the load is large, even if the temperature change and the difference between the temperature difference and the precedent temperature difference are the same as in the case of a small load, it cannot be said that the temperature in the car will be changed in the same way by the same correction value for the cooling power. The outside air temperature will be cited as an example of the load of the cooling system. When the outside temperature is high, since a large amount of heat transfers to the inside of the car through the wall and hot air enters the inside of the car due to drafts or by ventilation, the temperature in the car is difficult to lower by increasing the cooling power in the same way as in the case of a lower outside air temperature and, if the cooling power is reduced, the temperature in the car rises in a short time. On the other hand, if the outside air temperature is low, even with a little increase in the cooling power, the temperature in the car is easily lowered and, even if the cooling power is reduced, the temperature in the car is not raised so much. The same may be said of the amount of radiant heat by solar radiation or the like and the number of passengers. In this way, the state of the ambient load exerts great influence on the operation of the air conditioner. In such cases, it is impossible to calculate the correction value with due consideration of the load by a conventional calculation method. As a result, it is impossible to follow the change in the load and the temperature in the car disadvantageously becomes too low or too high.
In the above-described control methods, control is carried out on the assumption that the temperature in the car is kept constant. The human thermesthesia, however, is not determined merely by the air temperature but it is determined by the amount of heat produced within the human body and the amount of heat dissipated to the outside of the human body. If the amount of dissipated heat is large, a human being feels cold, while if it is small, he feels hot. The amount of dissipated heat is determined by temperature, radiation, air flow, humidity, etc. For example, if the outside air temperature is high, the amount of heat dissipated to the outside of the human body is reduced, and the human being feels hot, while if the outside air temperature is low, the amount of heat dissipated to the outside of the human body is increased, and the human being feels cold. As to radiation, if there is warm heat radiation, the amount of heat dissipated to the outside of the human body is reduced, while if there is cold heat radiation, the amount of heat dissipated to the outside of the human body is increased. As to air flow, if a large amount of wind blows against the human body, the heat on the surface of the human body is lost and the amount of heat dissipated to the outside of the human body is increased, while if the amount of wind is small, the amount of dissipated heat is reduced. In dissipating heat, a human being dissipates water out of the human body. If the balance between the amount of heat produced in the human body and the amount of dissipated heat is lost, the human being perspires in order to dissipate more heat. When the perspiration is evaporated, the heat on the surface of the human body is lost, thereby increasing the amount of dissipated heat and controlling the body temperature. However, if the ambient humidity is high, perspiration is unlikely to evaporate, and the amount of heat dissipated from the human body is reduced, so that the human being feels hot. In this way, temperature, radiation, air flow, humidity, etc. play an important role in the human thermesthesia. In heating or cooling a certain space, the temperature difference between the upper portion and the lower portion must be particularly take into consideration. The human thermesthesia is said to be determined by the temperature at his feet. Even if the temperature at the upper half of the body is high, if the temperature at his feet is low, the human being feels cold. On the other hand, even if the temperature at the upper half of the body is comparatively low, if the temperature at his feet is high, the human being feels warm. In heating or cooling a car, since the doors are opened when the train reaches a station and a large amount of ventilating air flows, the temperature in the car is unlikely to become stable. When a great number of passengers are in the car as in a commuter train, the air is unlikely to flow vertically in the car. For these reasons, a temperature difference is apt to arise between the upper portion and the lower portion. It is therefore important to heat or cool the car in due consideration of the temperature difference between the upper portion and the lower portion of the car.
In conventional control methods, however, the heating/cooling operation is carried out so that the temperature in the car is kept constant, so that the human thermesthesia changes with a change in the radiation, air flow or the temperature change between the upper portion and the lower portion of the car. The passengers therefore feel unfavorably hot or cold in spite of the target temperature.


A TAB (tape automated bonding) tape of high precision is formed without the deformations of its conductor pattern and the like and which is hermetically sealed with resin. The method for producing a TAB tape includes punching required holes, such as a device hole 14 and the like, in a metal plate 10 coated with an insulating adhesive layer 12 over the area where a conductor pattern is to be formed; and forming a required conductor pattern 24 by bonding a conductor metal foil onto the adhesive layer and by etching the conductor metal foil. Thus, the material cost of this TAB tape can be reduced and the production of this tape is facilitated.

1. Field of the Invention
The present invention relates to a tape automated bonding tape, hereinafter referred to as "TAB tape" and a method for producing the same.
2. Description of the Related Art
A TAB tape known in the art comprises a base film having an electrical insulating property and a conductor pattern formed on the base film. Such a TAB tape is characterized in that it can provide an extremely fine conductor pattern.
For producing a TAB tape, its conductor pattern is made by forming such conductor film as copper foil and the like on base film and then by etching the conductor film in the shape of a required pattern. Since the conductor film is supported on the base film of the TAB tape, it becomes possible to use a conductor film which is much thinner than a conventional metal lead frame and to form a conductor pattern of high-density which cannot be formed by such a conventional metal lead frame.
Because the base film of the TAB tape supports the conductor pattern as mentioned above, this base film itself must have an electrical insulating property. In addition, this base film must have a certain heat-resisting property, since the TAB tape is hermetically sealed with resin after a semiconductor chip is mounted on thereon. Therefore, a heat-resisting plastic film such as polyimide film or the like is used as the base film.
However, such a known TAB tape has the following problems that; the plastic film such as polyimide film or the like used as the base film is relatively expensive material; the base film has moisture-absorbency and this causes cracks in the sealed resin after being hermetically sealed with resin; the adhesiveness between the base film and the sealed resin is not always satisfactory; because of the softness and low rigidity of the base film, the conductor pattern is subject to be deformed; the deformations of the sprocket holes formed in the base film cause insufficient positioning accuracy; and the difference between the coefficient of thermal expansion of the conductor pattern and that of the base film causes warps in the attached condition between the base film and the conductor pattern.