Zero-Velocity Detection Method Based on Ultrasonic Ranging Assistance

The accumulated error in inertial pedestrian navigation can be transplanted through the zero-velocity correction algorithm, and the zero-velocity detection algorithm at this stage has the problems of single threshold, easy to miss detection and false detection, large calculation amount and large calculation delay. In order to solve these problems, an ultrasonic ranging auxiliary zero-velocity detection method is proposed. The foot spacing is measured in real time by an ultrasonic sensor placed on both feet, and then a time constraint is added to the Generalized Likelihood Ratio (GLRT) method using the time relationship between the shortest foot spacing and the zero-velocity interval. Experiments show that the accuracy of the proposed algorithm is better than that of the single threshold method under different gait states, and the average accuracy is above 95%. And due to the characteristics of high ultrasonic short-distance accuracy and small size, this method has simple calculation and small delay, which has practical application value.