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This paper describes the design of a light-weight and compact robotic gripper for automated harvesting of crops, including vegetable crops such as tomatoes, cucumbers, green onion, radish, and lettuce, growing in biomass production chambers. Because these crops vary significantly in their shape, size and rigidity, the gripper features soft fingertips with embedded grasping force sensor, a two degree-of-freedom (DOF) parallel jaw to facilitate alignment with crop objects to be harvested, and a two-DOF parallel cutting device to ensure complete separation of crop objects from plants during harvesting. A microcontroller system is integrated into the gripper for control of grasping and cutting.

A robot end effector is described in this paper that has been designed for NASA's Bioregenerative Planetary Life Support Systems Test Complex (BIO-Plex). An adapter concept allows the end effector to carry different types of sensor/probe modules and plant sampling mechanisms. These adapter modules will provide rapid and automatic configuration for a variety of tasks ranging from measurement of environmental conditions to tissue sampling and storage. In the paper, the prototype end effector and climatic sensors adapter that have been constructed are described, along with the biomass production robot system with which it is integrated.

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.