A Digital Controller for Horizontal Angular Motion of the FJSRL Seismic Isolation Platform.

Abstract

This study is part of a continuing effort to develop a stochastic controller for the angular motion about a horizontal axis of the Seismic Isolation Platform at the Frank J. Seiler Research Laboratory. The design of a digital controller is investigated based on the assumption that a Kalman filter would provide sufficiently accurate estimations of the states of the system. The design specifications are to maintain angular position within + or - 0.001 arcseconds and angular velocity within + or - 1.6 x 0.00001 arcseconds per second for a step function of 1.25 ft-lbs applied to the platform. Discrete models for the platform and two actuators are developed. The discrete models are used to design a controller for each actuator. A controller for the pneumatic actuator is designed to force the platform to a zero steady-state position. An optimal controller, which regulates the closed pneumatic loop, is designed for the shaker actuator. A theoretical evaluation of the control system shows angular position is maintained within + or - 2.81 x 0.0001 arcseconds and angular velocity has a peak overshoot of 2.24 x 0.01 arcseconds per second but settles to within the design specification in 0.08 seconds.

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1976
Accession Number
ADA027433

Entities

People

  • Martin J. Burkhart

Organizations

  • Air Force Institute of Technology

Tags

DTIC Thesaurus Topics

  • Actuators
  • Angular Motion
  • Control Systems
  • Filters
  • Hydraulic Equipment
  • Kalman Filters
  • Mechanical Equipment
  • Platforms
  • Pneumatic Actuators
  • Specifications
  • Steady State
  • Step Functions
  • Test And Evaluation

Readers

  • Astronomy and Astrophysics.
  • Control Systems Engineering.
  • Robotics and Automation.