Type synthesis of 4-DOF nonoverconstrained parallel mechanisms based on screw theory

Abstract

A systematic method is developed for the type synthesis of 4-DOF nonoverconstrained parallel mechanisms with three translations and one rotation inspired by the design of H-4. First, the motion requirements of primary platform and secondary platform of the 4-DOF nonoverconstrained parallel mechanisms are analyzed, and the conflict between the number of actuators and the constraint system for nonoverconstrained parallel mechanism is solved. Then, the research topic of type synthesis of 4-DOF nonoverconstrained parallel mechanisms is transformed into the type synthesis of the secondary platform with three translational DOF linked by two chains. On the basis of the screw and reciprocal theory, all possible secondary limbs with 3-DOF, 4-DOF, and 5-DOF are synthesized, respectively. Finally, the configurations and spatial assembly conditions of all possible secondary limbs are provided and some typical mechanisms are sketched as examples.

Structural Synthesis of Parallel Mechanisms with High Rotational Capability

“…A prominent characteristic for the H-4 family is that non-rigid moving platforms are used, after that many PMs with high rotational capability were synthesized utilizing the non-rigid moving platforms. Guo et al [20,21] developed a systematic method for the type synthesis of 4-DOF non-overconstrained parallel mechanisms with three translations and one rotation inspired by the H-4 manipulators and presented a class of 4-DOF non-overconstrained parallel mechanisms with large rotational workspace based on screw theory. Wang et al [22] synthesized a type of 2T3R and 3T3R PMs through constructing different kinds of configurable platforms, which possess high rotational abilities.…”

Research on Optimization Walking Robot Gait Planning Based on Human Bionics

“…Humanoid robot is a kind of human shape, and the ability to emulate some of the physical features of the human body, awareness and social skills and have some experience in the human part of the robot [6][7]. Humanoid robot is a mechanical and electrical, computer, sensors, control technology and materials, and many other subjects in one, is an important indicator of the level of a national high-tech development, therefore, the world's developed countries have invested heavily in research and development.…”

Type synthesis of 2R2T parallel mechanisms based on motion equivalent chain method

“…Liu et al 16 proposed a new family of 2T1R parallel manipulators with high rotational capability. Inspired by the design of H-4, Guo et al 17 developed a systematic method for the type synthesis of 4-DoF non-overconstrained parallel mechanisms with 3T1R motion.…”

“…Proc IMechE Part C: J Mechanical Engineering Science 228(17) at WEST VIRGINA UNIV on July 1, 2015 pic.sagepub.com Downloaded from…”