面向机器人运动跟踪的电磁定位系统

Electromagnetic Localization and Orientation Method and System

电磁定位具有精度高、速度快和易实现等优点,所以对手术、室内和室外机器人跟踪是一个良好的选择。电磁定位以交变电磁信号作为源信号。交变的电流信号激励发射线圈(信号激励部件)在空间中产生交变的电磁场,感应线圈(信号感应部件)在交变的电磁场中输出频率相同的信号。根据输出信号的幅值和相位信息,我们可以计算出感应线圈相对于发射线圈的位置和方向信息。本文面向机器人定位跟踪,介绍电磁定位系统的原理与实现,包括磁场模型、电磁定位算法与系统软硬件的搭建与实验。本文介绍两种不同的激励模式,分别为分时激励3轴正交发射线圈模式与同时激励2轴正交发射线圈模式,两种模式中的感应线圈均采用3轴正交线圈。实验结果表明,定位系统可以达到1mm的定位精度。

Electromagnetic localization and orientation method has the advantages of high accuracy, high speed and high applicability, so that it is a reasonable choice to be used in surgical, indoor and outdoor robots. It uses alternating signals as excitation source. The generating coils (used as the excitation part) are applied with low-frequency AC currents to generate alternating electromagnetic field in space, while sensor coils (used as the sensing part) output the same frequency signal. By using the amplitude and phase information of the output signals from the sensor coils, the position and orientation information of the sensor coils related to generating coils can be calculated. In this paper, the electromagnetic localization and orientation system is presented toward the robot localization, including the magnetic model, localization algorithm and the hardware\software of the system. Two different excitation methods are used in the system, which are the time-sharing with 3-axis generating coils and phase-division with 2-axis generating coils. Sensor coils used in these two types are 3-axis coils. Experimental results show that the system can have a good accuracy with 1 mm.