Effects of Joint Clearance on the Motion Accuracy of Robotic Manipulators

Abstract

Accuracy is one of the key features that improves the quality of robotic manipulators for many industrial and medical applications. Even with an accurate design and manufacturing process, clearance problems in joints cannot be eliminated in articulated systems. This leads to a loss of accuracy in robotic manipulation. In this study, the effects of joint clearance in a robotic system are investigated. The need for the trajectory of end effector is considered to analyse the motion sensitivity. The kinematics and dynamics of a six-DOF robot with joint clearance are evaluated relative to a robot without joint clearance. Different scenarios for clearance values and working periods are performed to fulfil the required motion task. A neural model is also used to predict the trajectory deviations during the working process. The results show that clearance has a significant role in the motion sensitivity of robotic manipulations. Trajectory errors can also be determined by using a dynamic neural predictor with suitable input variables.

Control System Design for a Centrifuge Motion Simulator Based on a Dynamic Model

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Task Location to Improve Human–Robot Cooperation: A Condition Number-Based Approach

“…As shown from the obtained results, the proposed approach, which is based on the condition number index, contributes in improving the HRI in terms of the achieved accuracy and the stability as well as the human comfort, but at the expense of the task speed. Accuracy is a very important and crucial factor in HRI [57][58][59], particularly in some robotic applications such as surgical tasks, assembly tasks, transferring objects, and welding processes. The results from the current approach are compared with the previous approach [26] based on the manipulability index in Table 4.…”

Optimal Placement of Vibration Sensors for Industrial Robots Based on Bayesian Theory

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