In order to meet the demands of simplicity and reliability in active control systems for flexible structures, an inexpensive active truss element and control law has been developed in this research. A decentralized switching control law is used along with a compressible fluid in the truss element in order to dissipate energy during the motion of the structure. However, the energy is not absorbed in the same manner as a conventional viscous damper. The truss element retains its maximum stiffness, but has a reset-able nominal unstressed length. Energy is absorbed in the working fluid of the truss element through heat transfer to the environment when the nominal length is reset at the proper switching times. The control law is insensitive to changes in structural parameters such as mass, stiffness, and damping. In this paper, a mathematical model for the system is presented along with a stability analysis and experimental results.
[1]
Zexiang Li,et al.
Control of seismic-excited buildings using active variable stiffness systems
,
1994,
Proceedings of 1994 American Control Conference - ACC '94.
[2]
Robert D. Hanson,et al.
Electrorheological dampers and semi-active structural control
,
1994,
Proceedings of 1994 33rd IEEE Conference on Decision and Control.
[3]
W. N. Patten,et al.
Semiactive control of civil engineering structures
,
1994,
Proceedings of 1994 American Control Conference - ACC '94.
[4]
George Leitmann,et al.
Semiactive control of a vibrating system by means of electrorheological fluids
,
1993
.