Control strategies for active lower extremity prosthetics and orthotics: a review

Journal of NeuroEngineering and Rehabilitation - Tập 12 - Trang 1-30 - 2015
Michael R Tucker1, Jeremy Olivier2, Anna Pagel3, Hannes Bleuler2, Mohamed Bouri2, Olivier Lambercy1, José del R Millán4, Robert Riener3,5, Heike Vallery3,6, Roger Gassert1
1Rehabilitation Engineering Lab, Department of Health Sciences and Technology, Zürich, Switzerland
2Robotic Systems Laboratory, Institute for Microengineering, EPFL, Lausanne, Switzerland
3Sensory Motor Systems Lab, Department of Health Sciences and Technology, Zürich, Switzerland
4Defitech Chair in Non-Invasive Brain-Machine Interface, Center for Neuroprosthetics, Institute of Bioengineering, EPFL, Lausanne, Switzerland
5Faculty of Medicine, Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zürich, Switzerland
6Faculty of Mechanical, Maritime and Materials Engineering, department of Biomechanical Engineering, Delft University of Technology, Delft, The Netherlands

Tóm tắt

Technological advancements have led to the development of numerous wearable robotic devices for the physical assistance and restoration of human locomotion. While many challenges remain with respect to the mechanical design of such devices, it is at least equally challenging and important to develop strategies to control them in concert with the intentions of the user. This work reviews the state-of-the-art techniques for controlling portable active lower limb prosthetic and orthotic (P/O) devices in the context of locomotive activities of daily living (ADL), and considers how these can be interfaced with the user’s sensory-motor control system. This review underscores the practical challenges and opportunities associated with P/O control, which can be used to accelerate future developments in this field. Furthermore, this work provides a classification scheme for the comparison of the various control strategies. As a novel contribution, a general framework for the control of portable gait-assistance devices is proposed. This framework accounts for the physical and informatic interactions between the controller, the user, the environment, and the mechanical device itself. Such a treatment of P/Os – not as independent devices, but as actors within an ecosystem – is suggested to be necessary to structure the next generation of intelligent and multifunctional controllers. Each element of the proposed framework is discussed with respect to the role that it plays in the assistance of locomotion, along with how its states can be sensed as inputs to the controller. The reviewed controllers are shown to fit within different levels of a hierarchical scheme, which loosely resembles the structure and functionality of the nominal human central nervous system (CNS). Active and passive safety mechanisms are considered to be central aspects underlying all of P/O design and control, and are shown to be critical for regulatory approval of such devices for real-world use. The works discussed herein provide evidence that, while we are getting ever closer, significant challenges still exist for the development of controllers for portable powered P/O devices that can seamlessly integrate with the user’s neuromusculoskeletal system and are practical for use in locomotive ADL.

Tài liệu tham khảo

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