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Robot calibration is often used synonymic for parametric robot calibration. Non-parametric robot calibration circumvents the parameter identification. Used with serial robots, it is based on the direct compensation of mapped errors in the work space. Used with parallel robots, non-parametric calibration can be performed by the transformation of the configuration space. Parametric robot calibration is the process of determining the actual values of kinematic and dynamic parameters of an industrial robot (IR). Kinematic parameters describe the relative position and orientation of links and joints in the robot while the dynamic parameters describe arm and joint masses and internal friction. A calibrated robot has a higher ''absolute'' positioning accuracy than an uncalibrated one, i.e., the real position of the robot end effector corresponds better to the position calculated from the mathematical model of the robot. Absolute positioning accuracy is particularly relevant in connection with robot exchangeability and off-line programming of precision applications. Besides the calibration of the robot, the calibration of its tools and the workpieces it works with (the so-called ''cell calibration'') can minimize occurring inaccuracies and improve process security. ==Accuracy criteria and error sources== The international standard ISO 9283 is setting different performance criteria for IR and suggesting test procedures in order to obtain appropriate parameter values. The most important criteria, and also the most commonly used, are accuracy of pose (AP) and repeatability of pose (RP). Repeatability is particularly important when the robot is moved towards the command positions manually („Teach-In“). If the robot program is generated by a 3D simulation („off-line programming“), absolute accuracy is vital, too. Both are generally influenced in a negative way by kinematic factors. Here especially the joint offsets and deviations in lengths and angles between the individual robot links take effect. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Robot calibration」の詳細全文を読む スポンサード リンク
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