Tuned vibration absorber for suppression of rest tremor in Parkinson's disease

Abstract

A simple approach for the suppression of the tremor associated with Parkinson's disease is presented. The proposed system is a tuned vibration absorber (TVA), which has been very effective in the suppression of vibrations in an experimental model of the human arm with two degrees of freedom. Theoretical and numerical methods were used to study the behaviour of the arm model and to develop an effective tremor reduction approach. Based on these studies, a vibration absorber was designed, tested numerically and fabricated for experimental testing. Experimental investigations indicated that optimum control performance was related to the position of the controller and the excitation frequency. With a distance of 160 mm from the end of forearm, the TVA was found to have the best performance, and, for different tremor frequencies, the vibration of the experimental model was reduced by more than 80%.

Admittance-Based Voluntary-Driven Motion With Speed-Controlled Tremor Rejection

“…In contrast, impedance control strategies for tremor suppression commonly rely on such information [33], [35], [26]. The controller used can be tuned successfully with no information concerning the mechanical properties of the human body part being affected.…”

“…Hashemi et al developed a similar concept called a tuned vibration absorber having 2 DOF (shoulder and elbow). The approach was tested with a simulated tremor for a single DOF vibration absorber [35]. The passive strategy by Rocon et al was also based on impedance control [18].…”

“…Specifically, the controller presented in section II.A tracks the voluntary motion while rejecting the tremor component, resulting in tremor attenuation. Since in this line of research simulation systems are indicated and frequently employed [26], [35], [36], [40], [41] as they allow verification of the approaches prior to obtaining access to persons with tremor, this manuscript presents in section II.B a benchtop simulator that was developed specifically to validate the proposed approach. Parametric stability is demonstrated for a generic tremor suppression simulator in section II.C.…”

An optimized method for tremor detection and temporal tracking through repeated second order moment calculations on the surface EMG signal

“…Several studies aimed at understanding, characterizing and controlling tremor, approaching the problem through the use of different techniques [18][19][20][21], mainly based on the use of Inertial Measurement Units (IMUs) capable to describe tremor from a biomechanical point of view.…”

“…Moreover, based on the recent attempts to reduce tremor by different approaches [19][20][21][24][25][26][27], a correct detection and timing of the tremor bursts could be used as a tool to gather further information on bioelectrical activity and to drive systems for tremor control and reduction.…”