tailieunhanh - Sensing Intelligence Motion - How Robots & Humans Move - Vladimir J. Lumelsky Part 11

Tham khảo tài liệu 'sensing intelligence motion - how robots & humans move - vladimir j. lumelsky part 11', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 276 MOTION PLANNING FOR THREE-DIMENSIONAL ARM MANIPULATORS We will first analyze the PPP arm Section an arm with three sliding prismatic joints it is often called the Cartesian arm and will develop a sensor-based motion planning strategy for it. Similar to the 2D Cartesian arm the SIM algorithm for a 3D Cartesian arm turns out to be the easiest to visualize and to design. After mastering in this case the issues of 3D algorithmic machinery in Section we will turn our attention to the general case of an XXP linkage. Similar to the material in Section some theory developed in Section and Sections to is somewhat more complex than most of other sections. As before we assume that the arm manipulator has enough sensing to sense nearby obstacles at any point of its body. A good model of such sensing mechanism is a sensitive skin that covers the whole arm body similar to the skin on the human body. Any other sensing mechanism will do as long as it guarantees not missing potential obstacles. Similar to the algorithm development for the 2D case we will assume tactile sensing As was shown in prior chapters the algorithmic clarity that this assumption brings is helpful in the algorithm design. We have seen in Sections and that extending motion planning algorithms to more information-rich sensing is usually relatively straightforward. Regarding the issues of practical realization of such sensing see Chapter 8. THE CASE OF THE PPP CARTESIAN ARM The model definitions and terminology that we will need are introduced in Section . The general idea of the motion planning approach is tackled in Section . Relevant analysis appears in Sections and . We formulate in particular an important necessary and sufficient condition that ties the question of existence of paths in the 3D space of this arm to existence of paths in the projection 2D space Theorem . This condition helps to lay a foundation for growing 3D path .