Feasibility of a Hydraulic Power Assist System for Use in Hybrid Neuroprostheses

Feasibility of using pressurized hydraulic fluid as a source of on-demand assistive power for hybrid neuroprosthesis combining exoskeleton with functional neuromuscular stimulation was explored. Hydraulic systems were selected as an alternative to electric motors for their high torque/mass ratio and ability to be located proximally on the exoskeleton and distribute power distally to assist in moving the joints. The power assist system (PAS) was designed and constructed using off-the-shelf components to test the feasibility of using high pressure fluid from an accumulator to provide assistive torque to an exoskeletal hip joint. The PAS was able to provide 21 Nm of assistive torque at an input pressure of 3171 kPa with a response time of 93 ms resulting in 32° of hip flexion in an able-bodied test. The torque output was independent of initial position of the joint and was linearly related to pressure. Thus, accumulator pressure can be specified to provide assistive torque as needed in exoskeletal devices for walking or stair climbing beyond those possible either volitionally or with electrical stimulation alone.

[1]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[2]  R. Stephenson.  A and V , 1962, The British journal of ophthalmology.

[3]  T. Bajd,et al.  Gait restoration in paraplegic patients: a feasibility demonstration using multichannel surface electrode FES. , 1983, Journal of rehabilitation R&D.

[4]  Ian W. Hunter,et al.  A comparative analysis of actuator technologies for robotics , 1992 .

[5]  E. B. Marsolais,et al.  Function and strength of electrically stimulated hip flexor muscles in paraplegia , 1994 .

[6]  E. Marsolais,et al.  Synthesis of paraplegic gait with multichannel functional neuromuscular stimulation , 1994 .

[7]  H. Hermens,et al.  Paraplegic locomotion: a review , 1996, Spinal Cord.

[8]  Ben Heller,et al.  The use of elastic element in a hybrid orthosis for swing phase generation in orthotic gait , 2000 .

[9]  V. Dietz,et al.  Functional electrical stimulation for grasping and walking: indications and limitations , 2001, Spinal Cord.

[10]  R. Triolo,et al.  Consumer perspectives on mobility: implications for neuroprosthesis design. , 2002, Journal of rehabilitation research and development.

[11]  William K Durfee,et al.  Design and simulation of a pneumatic, stored-energy, hybrid orthosis for gait restoration. , 2005, Journal of biomechanical engineering.

[12]  Homayoon Kazerooni,et al.  Exoskeletons for human power augmentation , 2005, 2005 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[13]  Sung Jae Kang,et al.  Hip Joint Control of PGO for Paraplegics , 2006 .

[14]  R. Kobetic,et al.  Design of a Variable Constraint Hip Mechanism for a Hybrid Neuroprosthesis to Restore Gait After Spinal Cord Injury , 2008, IEEE/ASME Transactions on Mechatronics.

[15]  Marcos Pinotti,et al.  Hip orthosis powered by pneumatic artificial muscle: voluntary activation in absence of myoelectrical signal. , 2008, Artificial organs.

[16]  William Durfee,et al.  Single channel hybrid FES gait system using an energy storing orthosis: Preliminary design , 2009, 2009 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[17]  Scott Tashman,et al.  Development of hybrid orthosis for standing, walking, and stair climbing after spinal cord injury. , 2009, Journal of rehabilitation research and development.

[18]  Michael A. Peshkin,et al.  A Highly Backdrivable, Lightweight Knee Actuator for Investigating Gait in Stroke , 2009, IEEE Transactions on Robotics.

[19]  José Luis Pons Rovira,et al.  Neurorobotic and hybrid management of lower limb motor disorders: a review , 2011, Medical & Biological Engineering & Computing.

[20]  Jerry E Pratt,et al.  Design and evaluation of Mina: A robotic orthosis for paraplegics , 2011, 2011 IEEE International Conference on Rehabilitation Robotics.

[21]  Jicheng Xia,et al.  Tiny hydraulics for powered orthotics , 2011, 2011 IEEE International Conference on Rehabilitation Robotics.

[22]  Daniel P. Ferris,et al.  Invariant hip moment pattern while walking with a robotic hip exoskeleton. , 2011, Journal of biomechanics.

[23]  Hugo A. Quintero,et al.  A Powered Lower Limb Orthosis for Providing Legged Mobility in Paraplegic Individuals. , 2011, Topics in spinal cord injury rehabilitation.

[24]  José Luis Pons Rovira,et al.  Online Assessment of Human-Robot Interaction for Hybrid Control of Walking , 2011, Sensors.

[25]  A. Esquenazi,et al.  Safety and tolerance of the ReWalk™ exoskeleton suit for ambulation by people with complete spinal cord injury: A pilot study , 2012, The journal of spinal cord medicine.

[26]  A. J. del-Ama,et al.  Review of hybrid exoskeletons to restore gait following spinal cord injury. , 2012, Journal of rehabilitation research and development.

[27]  L. Mertz,et al.  The Next Generation of Exoskeletons: Lighter, Cheaper Devices Are in the Works , 2012, IEEE Pulse.

[28]  A. Esquenazi,et al.  The ReWalk Powered Exoskeleton to Restore Ambulatory Function to Individuals with Thoracic-Level Motor-Complete Spinal Cord Injury , 2012, American journal of physical medicine & rehabilitation.

[29]  Michael Goldfarb,et al.  Enhancing stance phase propulsion during level walking by combining fes with a powered exoskeleton for persons with paraplegia , 2012, 2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[30]  S. Carda,et al.  Efficacy of a Hip Flexion Assist Orthosis in Adults With Hemiparesis After Stroke , 2012, Physical Therapy.

[31]  S. Kolakowsky-Hayner,et al.  Safety and Feasibility of using the EksoTM Bionic Exoskeleton to Aid Ambulation after Spinal Cord Injury , 2013 .