An Automated End Effector for Use with ISRU Tools

摘要

THE Canadian Space Agency (CSA) as part of its Exploration Surface Mobility (ESM) project has been developing ISRU specific tools capable of utilization at the end of a robotic manipulator arm. The tools, which include a 2 meter 7 DOF arm and a 1.5 m 6 DOF arm, are: a microscope, a mini corer sampler, a Power Socket Wrench Tool, a vibrating Scoop and a robotic gripper, are intended to be housed in a Tool Holster on a mobility chassis. Interchanging those tools is accomplished through the use of an Automated End Effector Exchanger (AEEE), affixed to the arm, and a mating Grapple Fixture (GF), upon which the end effector or tool is mounted. The AEEE is an active device and is primarily tasked with the actions required to engage the GF, with tool attached, thereby rigidizing the tool to the arm and also forcing power and data connections for the tool to make. When the tool is removed from service, the AEEE must also disconnect the power and data and "push" the GF out of its socket to ensure a positive decoupling action. A Grapple Fixture (GF) is required to couple to the AEEE. This passive coupling presents the power and data ports from the AEEE to a connection for the payloads and provides a base to transmit reaction forces from the tool through the arm. Load variances and capabilities of the AEEE/GF pair required a clean slate approach to the design of the AEEE/GF set. The use of the system in ISRU also dictates that the system must be robust and tolerant to a wide variety of work environments, most notably the dirty environment encountered in field missions such as DRATS and ISRU Missions on Mauna Kea or Axel Heiberg. The nature of ISRU is such that these tools will be at the dirty end of the activity, so designs must consider these environmental aspects at the outset. This paper will discuss the development of the ESM AEEE and GF as it pertains to ISRU implements.