搭载低成本MEMS-IMU的RTK接收机初始对准方法

Initial Alignment Method of RTK Receiver with Low-cost MEMS-IMU

搭载的低成本微机电系统惯性测量单元(micro-electro-mechanical system-inertial measurement unit, MEMS-IMU)的实时动态载波相位差分(real time kinematic, RTK)接收机的初始对准是一个关键的技术问题,也是目前惯导RTK的一个挑战。针对这个问题,提出一种基于梯度下降的惯导RTK初始对准方法,将多矢量定姿与梯度下降相融合,有效地提高了多矢量定姿的精度。通过仿真实验和现场实验验证改进算法的有效性。试验结果表明:在不使用任何附加传感器(如磁力计)的情况下,使用低成本MEMS-IMU,仅需2~3 s,就可以在91%的置信度下,对中杆倾斜40°范围内RTK的测量精度达到2.5 cm,该算法的精度和收敛速度都能很好地满足惯导RTK应用的要求。

The initial alignment of the real time kinematic(RTK)receiver onboard a low-cost micro-electro-mechanical system-inertial measurement unit(MEMS-IMU)is a key technical issue and a challenge for current inertial RTK.Aiming at this problem,an initial alignment method was proposed for inertial navigation RTK based on gradient descent,which combined multi-vector attitude determination with gradient descent,which effectively improved the accuracy of multi-vector attitude determination.The effectiveness of the improved algorithm was verified by simulation experiments and field experiments.The experimental results show that without using any additional sensors(such as magnetometers),using a low-cost MEMS-IMU,it takes only 2 to 3 s to tilt the centering rod within 40°with 91%confidence.The measurement accuracy of RTK reaches 2.5 cm,and the accuracy and convergence speed of the algorithm can well meet the requirements of inertial navigation RTK applications.