Tham khảo tài liệu 'advanced strategies for robot manipulators part 3', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Hyper Redundant Manipulators 51 Fig. 13. Camera looks to the center of the circle How to move the camera according to the steps of these algorithms The image behavior in accordance with camera s movements was studied. The effect of pan and tilt rotations on two points placed in a quadratic position on a circle was geometrically described. Coordinate transformation matrices corresponding to rotations with pan and tilt angles respectively for perspective transformation were used. The variation of the distance between the two points placed in a quadratic position on the circle and the centre of the circle depending of the tilt angle X is plotted bellow in Fig. 14. Fig. 14. Distance variation for quadratic positions The variation of the ratio of the two distances is plotted bellow in Fig. 15a. The plot from Fig. 15b shows how is transformed a rectangle inscribed in the circle and having the edges parallel with the axes OX and OY when a tilt rotation is performed. Theoretically by zooming the distance between the two points varies in a linear way as it is shown upper right. The image s segmentation is basically a threshold procedure applied to the image s histogram. All the procedures included in the calibration algorithms were mathematically proven. If the calibration algorithm was successfully applied then the system is ready to perform the visual servoing tasks. 52 Advanced Strategies for Robot Manipulators Fig. 15. a. Ratio distances variation b. Rectangle transformation and distance variation under zoom influence 5. A Compliance control of a hyper redundant robot This section treats a class of hyper redundant arms can achieve any position and orientation in 3D space and that can perform a coil function for the grasping. The arm is a high degree of freedom structure or a continuum structure but in this chapter a different technological solution is assumed. The general form of the arm is shown in Figure 16. It consists of a number N of elements cylinders made of .
