1. A data collection apparatus, comprising: a sensing unit for attaching to a structure or live subject for sensing a parameter of the structure or live subject, said sensing unit comprising a sensor, a first data storage device, and a transmitting device, said first data storage device for storing data from said sensor; a control unit separable from said sensing unit, said control unit comprising a data receiving device and a second data storage device different from said first storage device, said data receiving device to receive data transmitted from said data sensing unit, said second data storage device for storing said data received from said sensing unit; and a triggering device for modifying the storing of data being stored to said first data storage device or for initiating transmission of data from said sensing unit to said control unit, wherein said triggering device is controlled by a real time change in information about the structure or live subject.