tailieunhanh - Advances in Robot Manipulators Part 11

Tham khảo tài liệu 'advances in robot manipulators part 11', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 392 Advances in Robot Manipulators joint errors were chosen based on data sheets of commercially available standard actuators to A0 3 P RRR 40 ym T. It is important to note that in the non-redundant case the last element of AỚ vanishes. In Fig. 7 the optimized switching patterns Jopt of the actuator position Ỗ as well as the resulting mechanism pose errors Avy and A f are presented. The EE was moved along trajectory ti with a constant orientation of p -30 p 0 and p 30 denoted as tI -30 tj 0 and tj 30 respectively. The distance the EE moved along the trajectory is denoted as s. A significant improvement of the accuracy due to the kinematic redundancy 1 _ c I 1 c I 2 c 1 3 c I 1 s a íopt ÍI -30 c I 1 c 1 2 c 1 3 c I 1 s b ổopt tI 0 c I 1 c 1 2 c 1 3 c I 1 s c íOpt ÍI 30 1 _ c I 1 c I 2 c 1 3 c I 1 s c I 1 c I 2 c I 3 c I 1 s c I 1 c I 2 c 1 3 c I 1 s 8 8 Fig. 7. Simulation results while moving along trajectory ti -30 left tj 0 center and tj 30 right solid gray non-redundant mechanism dashed black optimized redundant mechanism using n Jh solid red optimized redundant mechanism using y Axh is well noticeable. . regarding tj -30 and tj 0 the maximal pose error occurring close to CI 2 is minimized by a reconfiguration of the mechanism according to the optimized switching patterns. Fig. 7 shows that both optimization criteria n Jh and y A h lead to similar switching patterns and to similar achievable accuracies. In Table 2 an overview of the maximal errors of the three triangular trajectories shown in Fig. 6 are given. In order to quantify the accuracy improvement the maximal translational Axymax and rotational error A f max of the moving platform over a complete trajectory was determined. The values represent the achievable accuracy of the associated mechanism. Additionally the percentage increase decrease of the kinematically redundant PKM in comparison to its non-redundant counterpart is given. Significant improvements of the