Canadarm or Canadarm1 (officially Shuttle Remote Manipulator System or SRMS, also SSRMS) is a series of robotic arms that were used on the Space Shuttle orbiters to deploy, manoeuvre, and capture payloads. After the Space Shuttle Columbia disaster, the Canadarm was always paired with the Orbiter Boom Sensor System (OBSS), which was used to inspect the exterior of the shuttle for damage to the thermal protection system. Development In 1969, Canada was invited by the National Aeronautics and Space Administration (NASA) to participate in the Space Shuttle program. At the time what that participation would entail had not yet been decided but a manipulator system was identified as an important component. Canadian company DSMA ATCON had developed a robot to load fuel into CANDU nuclear reactors; this robot attracted NASA's attention. In 1975, NASA and the Canadian National Research Council (NRC) signed a memorandum of understanding that Canada would develop and construct the Canadarm. NRC awarded the manipulator contract to Spar Aerospace (now MDA). Three systems were constructed within this design, development, test, and evaluation contract: an engineering model to assist in the design and testing of the Canadarm, a qualification model that was subjected to environmental testing to qualify the design for use in space, and a flight unit. End effector Anthony "Tony" Zubrzycki, a design engineer at DSMA ATCON, while seconded to SPAR, originated the concept for the Canadarm End Effector, inspired by an elastic band around his fingers. Zubrzycki formally presented this concept to NASA officials. Frank Mee, head of the SPAR mechanical development laboratory, built the end effector prototype based on Tony's concept and is credited by SPAR as the inventor of the Canadarm End Effector. The three-wire crossover design won over the claw-like mechanisms and others, such as the camera iris model, that were being considered. Controls and software The main control algorithms were developed by SPAR and by subcontractor Dynacon Inc. of Toronto. CAE Electronics Ltd. in Montreal provided the display and control panel and the hand controllers located in the Shuttle aft flight deck. Other electronic interfaces, servo amplifiers, and power conditioners located on the Canadarm were designed and built by SPAR at its Montreal factory. The graphite composite boom that provides the structural connection between the shoulder and the elbow joint and the similar boom that connects the elbow to the wrist were produced by General Dynamics in the United States. Dilworth,