Actuation Spaces Synthesis of Lower-Mobility Parallel Mechanisms Based on Screw Theory

Chinese Journal of Mechanical Engineering

Shihua Li¹  Yaxiong Ke¹  Jingjun Yu²  Yanxia Shan³ 

[1] Hebei Provincial Key Laboratory of Parallel Robot and Mechatronic Systems, Yanshan University, 066004, Qinhuangdao, China;School of Mechanical Engineering, Yanshan University, 066004, Qinhuangdao, China;Robotics Institute, Beihang University, 100191, Beijing, China;School of Mechanical Engineering, Yanshan University, 066004, Qinhuangdao, China;School of Liren, Yanshan University, 066004, Qinhuangdao, China;

关键词: Lower-mobility parallel mechanism;    Screw theory;    Actuation space;    Actuator placement;    Input selection;   

DOI  :  10.1186/s10033-021-00546-7

来源: Springer

【 摘 要 】

The lower-mobility parallel mechanism has been widely used in the engineering field due to its numerous excellent characteristics. However, little work has been devoted to the actuator selection and placement that best satisfy the system’s functional requirements during concept design. In this study, a unified approach for synthesizing the actuation spaces of both rigid and flexure parallel mechanisms has been presented, and all possible combinations of inputs could be obtained, laying a theoretical foundation for the subsequent optimization of inputs. According to the linear independence of actuation space and constraint space of the lower-mobility parallel mechanism, a general expression of actuation spaces in the format of screw systems is deduced, a unified synthesis process for the lower-mobility parallel mechanism is derived, and the efficiency of the method is validated with two selective examples based on screw theory. This study presents a theoretical framework for the input selection problems of parallel mechanisms, aiming to help designers select and place actuators in a correct and even optimal way after the configuration design.

【 授权许可】

CC BY