Modeling Robot Dynamic Performance for Endpoint Force Control

摘要

This thesis aims to understand the fundamental dynamic behavior of servo-controlled machinery in response to various types of sensory feedback. As an example of such a system, the author studies robot force control, a scheme which promises to greatly expand the capabilities of industrial robots by allowing manipulators to interact with uncertain and dynamic tasks. Implementations of compliant motion control strategies typically display extremely limited performance. Furthermore, the instabilities observed in these systems are generally not predicted by robot performance models. In this research, dynamic models are developed which allow the effects of actuator dynamics, structural flexibility, and workpiece interaction to be explored in the frequency and time domains. The models are used first to explain the causes of robot force control instability, and then to find methods of improving this performance. Emphasis is placed on the use of both laboratory testing and mathematical modeling to gain a fundamental understanding of machine dynamic behavior. The insights developed will help the designers of the next generation of automated manufacturing equipment to build more capable systems. (kr)