A Radar Sensor for Automatic Gait Speed Analysis in Walking Tests

Walking tests can provide an indicator of balance and fragility of people. They measure the gait speed and compare it to reference values related to various pathologies. We propose a radar sensor system that allows the evaluation of the gait speed in these tests in an automatic manner. The proposed approach consists of three phases; a first phase where the system automatically distinguishes the three sections of the test, namely walk #1, turn, and walk #2. Then, a second phase where the obtained signal is processed to evaluate the gait speed of the person. This is done through time-frequency analysis of the radar signal. In order to deal with the non-stationary nature of the radar signals, we consider the short-time Fourier transfer in our time-frequency analysis. The third phase consists in segmenting each walk into three segments, namely an acceleration zone, a measured-gait zone, and a deceleration zone. We provide a segmentation of the walking in order to automatically distinguish these zones. The proposed approach is validated using a Vicon motion-capture system, with a mean RMSE equal to 0.076 m/s. As compared to traditional techniques, our proposed system is automatic and does not require acceleration and deceleration zones.