Instrumented shoe-based foot clearance and foot-to-ground angle measurement system for the gait analysis

This paper presents a wireless gait analysis system that incorporates anatomically located infrared (IR) distance sensor on the shoe for the measurement of various gait parameters such as foot-to-ground angle (FGA), foot clearance (FC). The system has been validated against the BTS bioengineering 3D motion capture gold standard method in gait analysis laboratory with FC RMSE error of 6.31% of the full range and FGA RMSE error of 5.53% of the full range. The squared correlation coefficient r2 for FC and FGA is equal to 0.970 and 0.935, respectively. This system has a sensor position adjustment mechanism in two degrees of freedom, which facilitates the adaptability of the system to any foot size. The system is inexpensive, simple to use, and provides accuracy at par to the existing systems. This system finds application in a variety of clinical domains, for example, neurological disease diagnosis affecting ambulation such as Parkinson’s and cerebral palsy, gait rehabilitation, and sports fields. The future scope of this work includes validation of the shoe with different foot sizes and with different walking speed.