基于MEMS陀螺仪的农机转向轮角测量方法

针对传统连杆式轮角传感器安装困难,提出双MEMS陀螺仪轮角测量方法测量农机转向轮角。设计Kalman滤波器消除陀螺仪零偏、随机漂移和角度积分累积误差,实时反馈校正轮角测量值,实现农机转向轮角的精准测量。验证试验结果表明Kalman滤波器的校正效果良好,双MEMS陀螺仪测量转向轮角方法可行。对比试验结果表明,该方法转向轮角测量精度与传统轮角传感器测量精度相当,2.5m和1.5m上线距离均方根误差分别为0.26°和0.21°;动态响应性能略逊于传统角度传感器性能,分别采用本文方法和轮角传感器进行导航,拖拉机偏离目标航线2.5m时上线时间分别为17.9s和15s,偏离目标航线1.5m时上线时间分别为16.2s和14.2s。两组试验结果表明,本文提出的双MEMS陀螺仪转向轮角测量方法具有较好的测量精度,适用于农机转向轮角测量,满足导航作业的需求,能够替代传统的连杆式绝对轮角传感器。

Steering wheel angle measurement method of agricultural machinery based on dual MEMS gyroscope

Aiming at the difficulty in installing the traditional link-type wheel angle sensor, a dual MEMS gyroscope wheel angle measurement method is proposed to measure the steering angle of agricultural machinery. The Kalman filter is designed to eliminate the gyroscope’s zero offset, random drift, and cumulative error of angular integration, and to correct the wheel angle measurement value in real time to achieve accurate measurement of the steering wheel angle of agricultural machinery. The verification test results show that the Kalman filter has a good correction effect, and the method of measuring steering wheel angle by the dual MEMS gyroscope is feasible. The comparison test results show that the accuracy of the steering wheel angle measurement by this method is equivalent to that of traditional wheel angle sensors. The root-mean-square error of the line distance at 2.5 m and 1.5 m is 0.26° and 0.21°, respectively. Using the method of this paper and the wheel angle sensor for navigation respectively, the on-line time when the tractor deviates from the target course by 2.5 m is 17.9 s and 15 s, and when the tractor deviates from the target course by 1.5 m, the on-line time is 16.2 s and 14.2 s. The results of two sets of tests show that the dual MEMS gyroscope steering wheel angle measurement method proposed in this paper has good measurement accuracy, it’s suitable for agricultural machinery steering wheel angle measurement, meets the needs of navigation operations, and can replace the wheel angle sensor.