Design and development of an earth based experimental setup for testing algorithms on space robots

In space robots, coupling between the base and the arms causes the floating base to translate and rotate when the arms execute a maneuver, which is typically not seen in earth based robots. Since it is difficult to test developments in space robotics primarily due to the high cost and lack of access to robots in space, it is necessary to have physical systems that can mimic space conditions for experimental validation on earth. Among several options, the use of air bearings to build floating-base robots is one of the most effective. We describe the development of one such system that replicates zero gravity conditions for planar robots. Although similar systems exist elsewhere, the planar dual-arm space robot we have built is distinctive by being relatively lightweight, compact and modular. The setup can be used to test a wide range of experiments such as visual servoing, reactionless maneuvering and object grasping in space. In this paper, the approach taken during the development of both the hardware and software for the experimental setup are discussed. A few results obtained by numerical simulations as well as experimentation are also presented.