Kinematic Calibration of a Six-Legged Walking Machine Tool

Abstract This paper presents the kinematic calibration of a novel six-legged walking machine tool comprising mobile robot integrated with parallel manipulator on body. Each leg is 2-universal-prismatic-spherical (UPS) and UP mechanism, 6-PSU mechanism. The error models both subsystems are derived according to their inverse kinematics. objective function for each limb formulated as residual, i.e., deviation between actual computed joint coordinates. hip center first identified via sphere fitting, other parameters by solving individually using least-squares method. Thus, partially decoupled, complexities reduced. A method proposed legged overcome lack fixed base ground. experiment conducted validate method, where laser tracker used measurement equipment. entire identified, motion accuracy that significantly improved after calibration. Validation experiments performed evaluate positioning trajectory errors tool. results indicate legs improves not only individual subsystem but also cooperative among subsystems.