Instrumented insole system for ambulatory and robotic walking assistance: First advances

Current research highlights the emergent need for the development of wearable, calibrated, and accurate sensory systems for ambulatory human gait analysis. The purpose of this work is to develop a lightweight and calibrated instrumented insole system for the real-time monitoring of gait events in healthy, pathological and robotic-assisted gait. We designed the insole with four force sensing resistors (FSRs) to detect four gait events. We also implemented an electronic interface for the data acquisition and processing and the wireless transmission with the motherboard and the user interface. The validation involved 3 healthy female subjects, which reported that this prototype is flexible, lightweight and comfortable for daily usage. Results showed a maximal error of 6.02±3.02% in the detection of foot flat due to the small sensing area of FSRs placed on the first and fifth metatarsus. Future challenges comprise aesthetic and functional improvements and a more comprehensive validation.