Intelligent and Adaptive Control Applied to Powered Walkers - Project Summary/Abstract
Barron Associates, Inc. (BAI), teamed with the University of Virginia’s (UVA’s) Department of Orthopaedic Sur-
gery Motion Analysis and Motor Performance (MAMP) laboratory, proposes to develop a powered walker with
an advanced, intelligent, and adaptive control strategy for individuals with neuromuscular walking disabilities.
The aim of the control strategy is to provide powered assistance that optimally reduces the metabolic cost of
walking. The overarching goal of the proposed effort is to reduce the workload of walking, keeping this population
walking longer, providing critical exercise, continued muscle development, and improved quality of life.
The walker will be equipped with powered wheels driven by an onboard microprocessor that houses the control
algorithms. The controller will rapidly adjust the commanded inputs to account for the wide variability in user gait
characteristics and spasticity. There will be no need for manual control of the walker, as the walker will automat-
ically follow and support the user. The goal of the design is that it be equivalent to a virtual caregiver, or physical
therapist walking alongside, gently providing balance and locomotive support during ambulation.
Phase I Accomplishments: The major goals for Phase I were successfully accomplished, and include: (1)
construction of both an instrumented unpowered walker and a prototype powered walker; (2) development of
sophisticated, integrated human user/walker biomechanical models; (3) design of several candidate control ap-
proaches; and (4) completion of preliminary laboratory trials of the powered walker. The Phase I findings regard-
ing the powered walker, which included less required external work, very strong positive sentiment expressed
by trial participants and their family members, and statistically significant lower average heart rates using the
powered walker, clearly validate its potential benefits and acceptance by end users.
Phase II Aims: Advance the control strategies: Although the Phase I controllers worked very well, improved,
robust performance can be attained with more advanced, intelligent, and adaptive nonlinear control strategies.
Advance the biomechanical modeling: UVA’s MAMP laboratory will further mature their biomechanical mod-
els, increasing our knowledge and understanding of gait characteristics to aid in improving the control strategies.
Construct improved walkers for laboratory trials: A set of new walkers will be constructed in both child and
adult sizes, with improved mechanization and wireless transfer of gait data for post-trial analysis.
Conduct laboratory trials: Expanded laboratory trials will be conducted with a larger population of subjects
ranging from children to seniors, and spanning a variety of walking disabilities.
Design/develop prototype commercial walker: Construction of the prototype commercial walker will be per-
formed in Phase II. The commercial product will be called the SurePace Walker. The aim is to prepare for com-
mercialization by advancing the mechanization, addressing the regulatory approval and clearance processes,
and negotiating with existing walker manufacturers for follow-on teaming.
