Improved TDOA Two-Stage UWB Localization Algorithm For Indoor Mobile Robot

In order to improve the service quality of indoor mobile robots, ultra-wideband (UWB) is used as the research object, and the two-stage UWB positioning algorithm for indoor mobile robots with time difference is studied; The basic principle and error source of UWB localization algorithm based on TDOA for mobile robot are analyzed; two UWB positioning algorithms of improved time difference ranging and weighted position calculation are proposed. In the time difference ranging stage, the clock distribution measurement model and Gaussian filtering calculates the measured value of the distance difference of arrival (DDOA). In the weighted position calculation stage, the final target position coordinates are calculated according to the multiple measured values and the coordinates of the distance measuring point, which effectively reduces the time caused by the clock measurement. The static positioning is compensated separately to reduce the measurement error caused by the crystal oscillator of the hardware itself; the physical UWB module is built for experimental testing, the UWB device's ranging value is simulated, analyzed and evaluated, and the positioning accuracy is performed After the evaluation and error compensation, the two-stage UWB positioning algorithm is tested on the actual indoor robot. The experimental results show that the DDOA ranging value can be maintained within +/- 30cm based on the time difference ranging scheme, and the positioning accuracy after error compensation can meet the positioning requirements. It can be seen that the proposed two-stage UWB positioning algorithm for mobile robots without difference can meet the needs of indoor positioning, and has the advantages of low cost, low energy consumption, and high stability.