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This paper introduces a promising approach for developing an integrated traction motor drive based on the Integrated Modular Motor Drive (IMMD) concept. The IMMD concept strives to meet aggressive power density and performance targets by modularizing both the machine and power electronics and then integrating them into a single combined machine-plus-drive structure. Physical integration of the power electronics inside the machine makes it highly desirable to increase the power electronics operating temperature including higher power semiconductor junction temperatures and improved device packaging. Recent progress towards implementing the IMMD concept in an integrated traction motor drive is summarized in this paper. Several candidate permanent magnet (PM) machine configurations with different numbers of phases between 3 and 6 are analyzed to compare their performance characteristics and key application features.

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.

Conducting research to assess the impact of microgravity on plant growth and development requires a plant growth unit that has the capability to provide an enclosed, controlled environment chamber. Since plants are sensitive to a number of atmospheric gaseous materials, the chamber's atmosphere must be isolated from the space vehicle atmosphere. The plant growth unit must also be capable of removing any deleterious materials that may affect plant growth and development. The ASTROCULTURE™ plant growth unit (ASC-8), developed by Wisconsin Center for Space Automation and Robotics (WCSAR) at the University of Wisconson, was used to provide the desired environmental conditions required to support plant growth experiment during 9-day STS-95 mission. Effective control of chamber temperature, chamber humidity, plant water and nutrients delivery, and chamber carbon dioxide was maintained during the entire mission.