Estimating Physical Assistance Need Using a Musculoskeletal Model

Technologies that provide physical assistance during tasks are often required to provide assistance specific to the task and person performing it. An example is robotic rehabilitation in which the assistance-as-needed (AAN) paradigm aims to provide operators with the minimum assistance required to perform the task. Current approaches use empirical performance-based methods which require repeated observation of the specific task before an estimate of the needed assistance can be determined. In this paper, we present a new approach utilizing a musculoskeletal model (MM) of the upper limb to estimate the operator's assistance needs with respect to physical tasks. With capabilities of the operator defined at the muscular level of the MM, an optimization model is used to estimate the operator's strength capability. Strength required to perform a task is calculated using a task model. The difference or gap between the operator's strength capability and the strength required to execute a task forms the basis for the new AAN paradigm. We show how this approach estimates the effects of limb pose, load direction, and muscle impairments on a person's ability to perform tasks.

[1]  M. Pandy.  4 Moment A r m of a Muscle Force , 1999 .

[2]  Wendy M Murray,et al.  Muscle short-range stiffness can be used to estimate the endpoint stiffness of the human arm. , 2011, Journal of neurophysiology.

[3]  S. Delp,et al.  Moment-generating capacity of upper limb muscles in healthy adults. , 2007, Journal of biomechanics.

[4]  D. Reinkensmeyer,et al.  Effect of visual distraction and auditory feedback on patient effort during robot-assisted movement training after stroke , 2011, Journal of NeuroEngineering and Rehabilitation.

[5]  T. Hornby,et al.  Metabolic Costs and Muscle Activity Patterns During Robotic- and Therapist-Assisted Treadmill Walking in Individuals With Incomplete Spinal Cord Injury , 2006, Physical Therapy.

[6]  Oussama Khatib,et al.  Simulating the task-level control of human motion: a methodology and framework for implementation , 2005, The Visual Computer.

[7]  Ernest J. McCormick,et al.  Human Factors Engineering , 1985 .

[8]  D.J. Reinkensmeyer,et al.  Optimizing Compliant, Model-Based Robotic Assistance to Promote Neurorehabilitation , 2008, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[9]  D.J. Reinkensmeyer,et al.  Robotic movement training as an optimization problem: designing a controller that assists only as needed , 2005, 9th International Conference on Rehabilitation Robotics, 2005. ICORR 2005..

[10]  Dikai Liu,et al.  Towards using musculoskeletal models for intelligent control of physically assistive robots , 2011, 2011 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[11]  Günter Hommel,et al.  A Human--Exoskeleton Interface Utilizing Electromyography , 2008, IEEE Transactions on Robotics.

[12]  Scott L Delp,et al.  Generating dynamic simulations of movement using computed muscle control. , 2003, Journal of biomechanics.

[13]  David G Lloyd,et al.  Estimation of muscle forces and joint moments using a forward-inverse dynamics model. , 2005, Medicine and science in sports and exercise.

[14]  Dikai Liu,et al.  A task description model for robotic rehabilitation , 2012, 2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[15]  Scott L. Delp,et al.  A Model of the Upper Extremity for Simulating Musculoskeletal Surgery and Analyzing Neuromuscular Control , 2005, Annals of Biomedical Engineering.

[16]  Richard W. Bohannon,et al.  Relative Strength of Seven Upper Extremity Muscle Groups in Hemiparetic Stroke Patients , 1987 .

[17]  N. Hogan,et al.  Motions or muscles? Some behavioral factors underlying robotic assistance of motor recovery. , 2006, Journal of rehabilitation research and development.

[18]  Tyler Amell.  Shoulder, Elbow, and Forearm Strength , 2004 .

[19]  Rory A. Cooper,et al.  Strength and Disability , 2004 .

[20]  Clark R Dickerson,et al.  Comparison of model-predicted and measured moment arms for the rotator cuff muscles. , 2007, Clinical biomechanics.

[21]  M G Pandy,et al.  Musculoskeletal Model of the Upper Limb Based on the Visible Human Male Dataset , 2001, Computer methods in biomechanics and biomedical engineering.

[22]  Hermano Igo Krebs,et al.  Rehabilitation Robotics: Performance-Based Progressive Robot-Assisted Therapy , 2003, Auton. Robots.

[23]  M. Pandy.  Moment arm of a muscle force. , 1999, Exercise and sport sciences reviews.

[24]  F. Zajac.  Muscle and tendon: properties, models, scaling, and application to biomechanics and motor control. , 1989, Critical reviews in biomedical engineering.

[25]  R. M. Glaser,et al.  Improving the efficacy of electrical stimulation-induced leg cycle ergometry: an analysis based on a dynamic musculoskeletal model , 1993 .

[26]  S. Delp,et al.  Upper limb muscle volumes in adult subjects. , 2007, Journal of biomechanics.

[27]  D.J. Reinkensmeyer,et al.  Real-time computer modeling of weakness following stroke optimizes robotic assistance for movement therapy , 2007, 2007 3rd International IEEE/EMBS Conference on Neural Engineering.