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Finding Optimal Placement of the Almost Spherical Parallel Mechanism in the Recupera-Reha Lower Extremity Exoskeleton for Enhanced Workspace

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Advances in Service and Industrial Robotics (RAAD 2022)

Part of the book series: Mechanisms and Machine Science ((Mechan. Machine Science,volume 120))

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The ankle joint of an exoskeleton plays a vital role in maintaining balance and posture during locomotion by grounding the upper body’s weight. Parallel designs are advantageous for constructing ankle joints in exoskeleton but challenges include complex workspace analysis and finding the optimal placement in the overall structure of the exoskeleton. This paper presents a strategy for finding the optimal placement of the prototype Active Ankle 3[R2[US]] mechanism in the Recupera-Reha lower extremity exoskeleton for enhanced workspace. To this end, rotative inverse geometric model of the Active Ankle is exploited to find the alignment between principle human joint axes and axes along which the range of motion is optimum. It is demonstrated that by rotating the mechanism along the adduction-abduction axis and by selecting appropriate ball and socket joints, it is possible to enhance the usable workspace of the mechanism for the human wearing the exoskeleton.

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This research work is conducted at the Robotics Innovation Center, DFKI GmbH, Bremen, Germany in the M-RoCK project funded by the Federal Ministry of Education and Research with grant no. 01IW21002. Additionally, the author acknowledges the support of the Nigerian-German Academic Exchange Programme, sponsored by the DAAD.

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Correspondence to Ibrahim Tijjani .

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Tijjani, I. (2022). Finding Optimal Placement of the Almost Spherical Parallel Mechanism in the Recupera-Reha Lower Extremity Exoskeleton for Enhanced Workspace. In: Müller, A., Brandstötter, M. (eds) Advances in Service and Industrial Robotics. RAAD 2022. Mechanisms and Machine Science, vol 120. Springer, Cham.

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