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Maintaining thermal balance in a space-based plant chamber has proven to be difficult to achieve, particularly if the air temperature in the plant chamber is desired to be below that of the atmosphere of the space vehicle. Analysis of the thermal condition of a plant chamber has identified three heat sources as major contributions to this serious problem. The first is the input of radiant energy into the chamber required to support plant growth. The second is via thermal conduction through the chamber walls. The last major thermal input is from the fans and other electronic components embedded inside the chamber. Design solutions to achieve thermal balance are further exacerbated by virtue of the limited power availability, volume and mass restrictions, and safety considerations.

The adaptation to changes in human operator dynamics and changes in working environment dynamics can be an important issue in designing high performance telerobotic systems. This paper describes an approach to force control in telerobotic hand systems in which model reference adaptive control techniques are used to adapt to changes in human operator and working environment dynamics. The techniques have been applied to force-reflective control of a single degree-of-freedom telerobotic gripper system at Wisconsin Center for Space Automation and Robotics (WCSAR). This adaptive gripping system is described in the paper along with results of experiments with human subjects in which the performance of the adaptive system was analysed and compared to the performance of a conventional non-adaptive system. These experiments emphasized adaptation to changes in compliance of gripped objects and adaptation to the on-set of human operator fatigue.