This paper discusses the control problem of launching an open-loop unstable system from its resting state on a mechanical hard stop. Smooth state transition with the appropriate control mode is accomplished by fuzzy transition logic. A “soft tracking” algorithm with on-line trajectory planning is then employed to manage the system stabilization immediately following the launch. The strategies have been successfully applied to an experimental system consisting of a hydraulically balanced beam pivoted at its center.

1.
Bellman
,
R. E.
, and
Zadeh
,
L. A.
,
1970
, “
Decision-Making in a Fuzzy Environment
,”
Manage. Sci.
,
17
, pp.
141
164
.
2.
Kuipers B., and Astrom K., 1991, “The Composition of Heterogeneous Control Laws,” Proceedings of the 1991 American Control Conference, pp. 630–636.
3.
Zadeh
,
L. A.
,
1995
, “
Outline of a New Approach to the Analysis of Complex Systems and Decision Processes
,”
IEEE Trans. Syst. Man Cybern.
,
15
, pp.
28
44
.
4.
Yang, P. H., and D. M. Auslander, 1999, “Soft Tracking Control for Input Constrained Systems,” Proceedings of the 1999 American Control Conference, Vol. 4, p. 2496–2500.
5.
Spong, M., 1995, “The Swingup Control Problem for the Acrobot,” IEEE Control Syst. Mag., Feb.
6.
Yang
,
P. H.
,
Lemkin
,
M.
, and
Auslander
,
D. M.
,
1997
, “
Using a Hydraulically Balanced Beam in Control Education
,”
ASME J. Dyn. Syst., Meas., Control
,
119
, Dec., pp.
815
819
.
7.
Auslander, D. M., Ridgely, J., and Jones, J., 1996, “Real Time Software for Implementation of Feedback Control,” W. S. Levine, ed., The Control Handbook, CRC Press, pp. 323–343.
You do not currently have access to this content.