Visual Detection Method For End Trajectory Of Cable-Driven Parallel Mechanism

In recent years,more and more scholars have paid attention to and studied the parallel mechanism driven by flexible cables,which has the advantages of simple model,large workspace and low price.The study of the motion state of the end effector of the flexible parallel mechanism is an important index reflecting the motion state of the mechanism,and it is also a reference for mechanism simplification and fault diagnosis.Its detection accuracy is an important aspect to measure the structural performance of the mechanism.It is necessary to ensure that the end effector reaches the predetermined motion state.Therefore,it is of great significance to study the application of visual inspection method for end trajectory of cable-driven parallel mechanism.In this paper,the moving target tracking algorithm is discussed in depth.In this paper,the principle of CamShift algorithm is introduced in detail.Aiming at the problems of manual setting of initial search window and low stability of moving target tracking in traditional algorithm,the CamShift algorithm is improved on the basis of traditional algorithm,and the improved algorithm is used to track and detect the end effector of cable-driven parallel mechanism.The experimental results show that the improved CamShift algorithm successfully realizes the automation of the initial search window,and can track and detect moving objects stably and effectively.In this paper,the location algorithm of moving target is studied in depth.This paper analyses the location principle of the traditional Zernike moment sub-pixel edge location algorithm.On this basis,a new sub-pixel edge location algorithm based on improved Zernike moment is proposed,which combines the traditional Zernike algorithm with iteration method,and the error caused by the algorithm is analyzed and compensated.The performance of the improved algorithm is studied through simulation experiments.The simulation results show that the detection accuracy and stability of the improved algorithm are better than the traditional algorithm and the other two common location algorithms.The overall scheme of the visual inspection experimental platform is designed.According to the overall scheme,the hardware selection,installation and control software development of the visual inspection experimental platform are completed.The end trajectory of the cable-driven parallel mechanism is tested by using the visualinspection experimental platform,and the source of the error is analyzed.The experimental results show that under the same experimental environment,the more complex the end-effector motion trajectory is,the larger the error between the actual value and the theoretical value of the target trajectory obtained by visual detection will be;From the perspective of detection method,the detection accuracy of the improved algorithm in this paper is higher than that of the traditional algorithm,and it can detect the motion state of the end-effector more accurately.