Integrated identification and control of magneto-rheological dampers for manned space missions

Prolonged stay in space provokes physiological changes in astronauts. Hurdling negative effects of zero-g environment requires routine exercise. A lightweight, reliable treadmill platform utilizing a magnetorheological damper was modeled to suppress the vibration of the platform for this purpose, since a magnetorheological damper is a semi-active device that is maintenance free and requires low power. Immediate servicing would not be available in space applications; therefore, an adaptive inverse control algorithm was utilized so that the system would not be affected by the uncertainties and parameter changes that might happen within the system. The system is controlled via LQR and S/KS mixed sensitivity H∞ methods which produce the desired control force required from the damper. Adaptive inverse algorithm is the inverse function of the damper model, which uses the desired force as input and produces the control voltage that will be applied to the damper.