Robot kinematic calibration is an effective way to reduce the errors of kinematic parameters and improve the positioning accuracy of a robot. This paper presents a cost-effective kinematic calibration method for a hexapod robot that only needs a monocular camera and two planar markers. The markers are attached to the body and the foot-tip of the robot separately, and the robot’s six legs are calibrated one by one. The kinematic model and error model of the robot are established based on the local product of exponential (POE) model, and the calibration task is formulated as a nonlinear least squares problem where 24 unknown parameters are estimated for each leg. The proposed calibration procedure is successfully evaluated on a real hexapod robot, and the experimental results show that the robot can have a better walking performance after calibration.

机器人运动学标定是减少运动学参数误差、提高机器人定位精度的有效途径。本文提出了一种具有成本效益的六足机器人运动学校准方法，该方法只需要一个单目相机和两个平面标记。标记分别贴在机器人的身体和脚尖上，机器人的六条腿被一一标定。基于指数局部积（POE）模型建立机器人的运动学模型和误差模型，并将标定任务表述为非线性最小二乘问题，每条腿估计24个未知参数。所提出的校准程序在真实的六足机器人上成功评估，