A Novel Force-Controlled Spherical Polishing Tool Combined With Self-Rotation and Co-Rotation Motion

Abstract

In order to improve the polishing efficiency and aim at the problem that the positioning error of industrial robot will cause the fluctuation of polishing force and the instability of removal function, a novel force-controlled spherical polishing tool combined with self-rotation and co-rotation motion for automatic polishing process is presented. The spherical polishing tool, which is integrated into the end of arm of an industrial robot for workpiece profile polishing has a linear voice coil motor to provide compliance and polishing force in the polishing process. The fluctuation of the polishing force caused by the positioning error of the robot can be effectively reduced, and a stable symmetric Gaussian removal function can be obtained by optimizing the ratio of co-rotation to self-rotation speed of the end-effector. The main advantage of the polishing method is that the polishing force can be actively controlled according to the pre-planned polishing requirements. By measuring the responsiveness and the stability of the polishing force using the proposed end-effector, it is verified that the polishing method can better adapt to the fluctuation of the polishing force and has a good performance in achieving remarkable polishing force tracking. The effectiveness of the proposed polishing method in ensuring the stability of removal function and surface convergence efficiency is verified through polishing experiments. The robotic flexible polishing method has great application prospect in processing large-sized optical components. It significantly improves the precision of polishing force and the surface convergence efficiency of the workpiece. INDEX TERMS Polishing force, robotic flexible polishing, removal function, spherical polishing tool.

A High-Bandwidth End-Effector With Active Force Control for Robotic Polishing

“…From Fig. 9(a), it can be seen that the frequency response of the proposed end-effector was attenuated to -3 dB with a theoretical bandwidth of 1510 rad/s, which is a significant increase of 67.77% from the theoretical bandwidth of 900 rad/s obtained in a recent robotic polishing theoretical analysis [29]. When using the whole system shown in Fig.…”

“…Chen et al [28] developed a mini robot for polishing thin-walled blisks, which contains complex components such as a positioning table and eddy current damper. Wu et al [29] proposed a force-controlled spherical polishing tool combined with self-rotation and co-rotation motion for an automatic polishing process, which obtained a bandwidth frequency of 900 rad/s. Yang et al [30] designed a three degree-of-freedom (DOF) (i.e., two-rotational and one-translational (2R1T)) end-effector to perform continuous contact operations, which achieved a force control bandwidth of 15 Hz.…”

Investigations on the production of optical freeforms applying the advanced wheel polishing process

“…1) had been introduced by OptoTech back in 2013 as the outcome of an internal R&D project. Wu et al have recently published some closer investigations on the removal behaviour of such tools [3]. The A-WPT provides the specific advantages of a standard wheel polishing tool rotating around only one axis (high removal rates even at small polishing spot sizes, reduced tool wear) while combining them with a homogenization of the resulting micro texture on the polished surfaces by adding a second rotational axis.…”

Speed Adjustment on Variable Frequency Induction Motor Using PLC for Automatic Polishing Machine

“…Then in 1890, the development of the Ward-Leonard system was very meaningful for the evaluation of DC motor drives, which use generators and electric motors to drive DC motor drives. In the 1940s, all systems primarily used air conditioning to further develop the ward system -Leonard used an AC motor [8]. This system can increase ceramic output and improve quality.…”