Share Email Print

Proceedings Paper

Dynamic Composition and Execution of Behaviors in a Hierarchical Control System
Author(s): Thomas L. Skillman; Ken Hopping
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

The behavior of a system can be defined as its trajectory in state space. A system's behavior comes about through the interaction of its control law with the plant dynamics. In systems where the plant dynamics vary considerably a constant control law can lead to varying behaviors. A more consistent operation of a system can be attained by specifying the desired behavior and then, based on the current plant dynamics, selecting the appropriate control law. Assuming that only the lowest level of a hierarchical controller is responsible for selecting the appropriate control law, the rest of the hierarchy needs only to represent and operate on abstracted state spaces and behaviors. Here a hierarchical control system is presented that operates as a hierarchy of behaviors, rather than control laws, to achieve adaptive real-time control performance. A planning system at each level of the hierarchy composes sequences of behaviors that will implement a more abstract behavior specified by the next higher level. The first intermediate goal state generated by a plan is passed to the next lower level of the hierarchy as the goal state, and the planning sequence repeated. A set of relations is used to translate between the state abstractions at different levels. At the bottom level the behavior is mapped into a control law that will achieve the behavior when applied to the current plant dynamics. The system has been prototyped and demonstrated on a wheeled mobile robot platform with sonar range sensing.

Paper Details

Date Published: 1 March 1990
PDF: 13 pages
Proc. SPIE 1195, Mobile Robots IV, (1 March 1990); doi: 10.1117/12.969896
Show Author Affiliations
Thomas L. Skillman, Boeing High Technology Center (United States)
Ken Hopping, Boeing High Technology Center (United States)

Published in SPIE Proceedings Vol. 1195:
Mobile Robots IV
Wendell H. Chun; William J. Wolfe, Editor(s)

© SPIE. Terms of Use
Back to Top