Adaptive zero-speed interval detection method for pedestrian navigation system

Abstract

The invention discloses an adaptive zero-speed interval detection method for a pedestrian navigation system. According to a fixed threshold method, a zero-speed detection interval has the problems of false detection and missing detection under the walking condition with varying gait frequencies; by an adaptive threshold method, the relationship between a zero-speed interval detection threshold and the gait frequency of a pedestrian can be analyzed, so that the detection accuracy of a zero-speed interval is effectively improved. By carrying out a calibration experiment of a zero-speed point judging threshold under the condition with different gait frequencies, the functional relationship between a zero-speed detection threshold and the gait frequency is established, and the adaptive adjustment of the detection threshold and the accurate detection of a zero-speed point are achieved, so that the detection accuracy of the zero-speed interval is improved; by the adaptive zero-speed interval detection method, adaptive detection of the zero-speed interval can be achieved only by using output data of a gyroscope and three accelerometers in an inertial measurement unit, without needing to add or use other external sensors to assist the detection of the zero-speed interval, so that the detection method is simple and accurate.

Description

technical field [0001] The invention relates to the technical field of pedestrian navigation and positioning, in particular to an adaptive detection method for a zero-speed interval of a pedestrian navigation system. Background technique [0002] In an environment where the GPS signal fails or there is no beacon, it is very difficult to track and locate pedestrians in real time. In order to realize the self-localization of pedestrians in any environment, the pedestrian navigation system composed of small inertial measurement units can help pedestrians achieve continuous and autonomous positioning. Pedestrian navigation systems based on inertial measurement units usually use inertial navigation algorithms to calculate the position information of pedestrians, but the acceleration error in the integration process will cause the position error to grow cubically with time, and due to the low-cost inertial measurement used in pedestrian navigation systems The unit performance is ...

AI Technical Summary

Problems solved by technology

[0003] In the traditional zero-speed interval detection method, the threshold is a fixed value. When pedestrians walk with a constant gait frequency, the zero-speed interval in the gait can be extracted more accurately by setting a fixed threshold; however, the randomness of pedestrian movement in the actual process Irresistible, and it is impossible to maintain a constant gait frequency all the time

Therefore, when a pedestrian walks with a changing gait frequency, if a fixed threshold is still used as the set threshold, there will be false detections or missed detections in the detection results of the zero-speed interval

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