Tremor suppression through impedance control.

Biomechanics and Movement Science Program, University of Delaware, Newark 19716, USA.
IEEE Transactions on Rehabilitation Engineering 04/2000; 8(1):53-9. DOI: 10.1109/86.830949
Source: PubMed

ABSTRACT This paper presents a method for designing tremor suppression systems that achieve a specified reduction in pathological tremor power through controlling the impedance of the human-machine interface. Position, rate, and acceleration feedback are examined and two techniques for the selection of feedback coefficients are discussed. Both techniques seek a desired closed-loop human-machine frequency response and require the development of open-loop human-machine models through system identification. The design techniques were used to develop a tremor suppression system that was subsequently evaluated using human subjects. It is concluded that nonadaptive tremor suppression systems that utilize impedance control to achieve a specified reduction in tremor power can be successfully designed when accurate open-loop human-machine models are available.

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