Accession Number:

ADA196014

Title:

Simulation of a Two Link Robot Manipulator with Elastic Members

Descriptive Note:

Final rept. 1 Sep-6 May 1988

Corporate Author:

ARMY MILITARY PERSONNEL CENTER ALEXANDRIA VA

Personal Author(s):

Report Date:

1988-05-06

Pagination or Media Count:

125.0

Abstract:

The elastic behavior of the components of a robot manipulator will tend to induce both static and dynamic errors between desired and actual trajectories and end-effector positions. Currently, most researchers consider joint compliance - as opposed to link displacements - to be the dominant source of these errors. This conclusion is based on the the fact that when compared to the yielding typically seen in gears, motor shafts, bearings, etc., the links appear almost perfectly rigid. However, current efforts to lighten robot manipulators and increase their operating speeds also tends to increase the significance of link elasticity. This study considers the dynamic effects of elastic link displacements in a two-link robot manipulator as simulated by a hierarchy of models. In all, five separate system models are developed. The last model, TFTFEL, allows both manipulator links to bend in a single plane and to twist. Therefore, the effects of bending-torsion vibrations in each link may be observed when the manipulator attempts motion with an inertially asymmetric payload grasped in its end-effector. This elasto-dynamic behavior is simulated, and results indicate a definite disturbance of the joint angle trajectories. The use of structural damping to eliminate these high frequency vibrations and increase the manipulators accuracy is evaluated.

Subject Categories:

  • Manufacturing and Industrial Engineering and Control of Production Systems

Distribution Statement:

APPROVED FOR PUBLIC RELEASE