Two link joint flexible macro manipulator carrying a two-armed micro manipulator with a "satellite".

Feedback Control of a Macro/Micro Manipulator

The macro part of this manipulator features two 1.5m long links, each with built in joint flexibility. The two micro arms are similar to the ones on the free-flying space robots. The arm operates in a two dimensional space-like environment: the end-point floats on an air bearing over a large, flat granite table. Also shown is a small free floating object that the robot can catch and manipulate. An overhead vision system senses the end-point position of the arms as well as the position of the object

The goal of the research is to remove the human from the low-level control of moving each arm. Instead, the human should give tasks for the robot to complete autonomously. It is desired to have a low-level control loop that can accurately control the end-point of each micro arm. While much research has been done on controlling redundant robotic systems, many of these techniques break down when there is flexibility between the motor and the robot. Current research is on using techniques such as backstepping to account for the joint flexibility in combination with rigid robot redundancy management schemes.

A planned space macro/micro system is the SSRMS/SPDM

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