Locking control of underground signal lights based on improved Kalman filter and state observer

During underground ramp transportation in non-coal mines, traditional signal light locking control method is ineffective due to insufficient UWB dynamic positioning accuracy, long sampling interval of vehicle positioning cards, and data loss. Aiming at this problem, this paper proposed a locking control method of underground signal lights based on improved Kalman filter and state observer. The underground vehicle positioning principle based on UWB was analyzed, and a signal light logic determination method tailored to the characteristics of non-coal mine operation was provided. A strong tracking Kalman filter algorithm was introduced, and it was improved through strong tracking adaptive method. A time-varying fading factor was incorporated in the calculation of prediction errors, improving the positioning accuracy. According to the filtered posterior distance and speed values, the time for the vehicle to reach the threshold was predicted, solving the problem of control lag caused by discrete data acquisition and improving the reliability and timeliness of signal light locking. A remote state observer was used to evaluate the performance of signal light locking control. Based on statistics of the time domain automatic tracking, the quantitative evaluation of the locking reliability was realized. Simulation results demonstrated that after improving Kalman filter algorithm, the dynamic and static position errors of the vehicle were reduced by 25.67% and 27.19%, respectively, the dynamic and static speed errors were reduced by 25.28% and 34.73%, respectively. The logic response of the signal light threshold was faster. Results from underground industrial trials and applications showed that the success rate of underground signal locking was over 99.5% after using the strong tracking Kalman filter algorithm, which effectively improved the real-time performance and reliability of signal locking control of underground ramp intersections and ensured the safe driving of underground vehicles.