Design and Implementation of a Flexible Robot
Abstract
This report describes the design, implementation, and control of a robot that has low natural frequencies of vibration. Insights into the problems of designing joint and link flexibility are discussed. The deflection of the robot under gravity is correlated with the fundamental frequency of vibration. Different link geometries and materials are evaluated. The robot has three rotary actuators and two links, with two actuators at the base and the third as an elbow joint between the links. The links are interchangeable and the joints have a variable flexibility built in. The robot is controlled by three separate processors running on a VMEbus. A Sun 3/180 workstation provides the development environment. A collection of operator controls have been built including a panel to control the amplifiers and brakes, and a joystick for teleoperation. A PD servo loop runs the robot in either joint or cartesian space. Results from experiments on the control of residual vibration are presented. Three different motions of the arm have been studied: a constant vibrational frequency move, a changing vibrational frequency move, and a cartesian move. Impulse prefiltering and slowly accelerating moves are compared and shown to be effective at reducing residual vibration. Theses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1989
- Accession Number
- ADA216453
Entities
People
- Andrew D. Christian
Organizations
- Massachusetts Institute of Technology