Passive derivation of basic walker-assisted gait characteristics from measured forces and moments

This work describes a method that passively assesses basic walker-assisted gait characteristic, including heel strikes, toe-off events, as well as stride time, double support and right & left single support phases using only force-moment measurements from the walker's handles. The passively derived gait characteristics were validated against motion capture gait analysis and showed good correlations. This research is part of an effort that aims to identify user intent, from measuring forces and moments exerted on the handles of the walker as well as from perceiving the environment, and to incorporate identified intent into a passive shared steering control system for the walker. The primary focus of the work leading to This work is to identify the double support phase, and to engage the steering control at the beginning of this phase to maximize the user's stability. However, the application of the method presented and the instrumented walker can be extended to longitudinal outside the lab Gait assessment.

[1]  G.F. Harris,et al.  Walker-assisted gait in rehabilitation: a study of biomechanics and instrumentation , 2001, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[2]  Pradip Sheth,et al.  User intent in a shared control framework for pedestrian mobility aids , 2003, Proceedings 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2003) (Cat. No.03CH37453).

[3]  John G. Proakis,et al.  Digital Signal Processing: Principles, Algorithms, and Applications , 1992 .

[4]  Sean Graves,et al.  Effective Shared Control in Cooperative Mobility Aids , 2001, FLAIRS.

[5]  Sean Graves,et al.  An assistive robotic agent for pedestrian mobility , 2001, AGENTS '01.

[6]  A Fast,et al.  The instrumented walker: usage patterns and forces. , 1995, Archives of physical medicine and rehabilitation.