[01] Chen Wang, Friedrich-Wilhelm-Bessel-Institute Research Company, Bremen, Germany. [02] Henning Stoeppler, Friedrich-Wilhelm-Bessel-Institute Research Company, Bremen, Germany. [03] Oleg Ivlev, Friedrich-Wilhelm-Bessel-Institute Research Company, Bremen, Germany.

Pneumatic actuated rehabilitation robots are presently been developed worldwide because of their compliant behavior as a result of the following qualities they possess: natural compressibility of air, light weight and their high power to weight ratio. Hence the basic physical human-robot-interaction is given and can be further improved by using soft actuators with elastic chambers and assistive controllers. However, practical application and clinical deployment of pneumatic robots are limited due to the condition of a significant quantity of compressed air. Especially assistive acting robots with sophisticated control algorithms and high-dynamic servo valves often need a pneumatic line or large external supply. In this paper we propose a new assistive control algorithm, which can be implemented on microcontrollers, wherein the external compressed air supply is replaced by an integrated miniature pneumatic pump without a pressure tank and for the output, a simple proportional valve is utilized. As an application of this simplified control system, a mobile variant of a pneumatic elbow trainer with self-alignment has been constructed. The efficacy of the developed assistive control is demonstrated through experiments with healthy subjects.

Soft Robotic, Rehabilitation, Assistive Control, Compact, Internal Air Supply

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