%0 Journal Article
%T Kinematics, Singularity, and Workspaces of a Planar 4-Bar Tensegrity Mechanism
%A Zhifei Ji
%A Tuanjie Li
%A Min Lin
%J Journal of Robotics
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/967251
%X Compared with conventional mechanisms, tensegrity mechanisms have many attractive characteristics such as light weight, high ratio of strength to weight, and accuracy of modeling. In this paper, the kinematics, singularity, and workspaces of a planar 4-bar tensegrity mechanism have been investigated. Firstly, the analytical solutions to the forward and inverse kinematic problems are found by using an energy based method. Secondly, the definition of a tensegrity mechanism¡¯s Jacobian is introduced. As a consequence, the singularity analysis of the planar 4-bar tensegrity mechanism has been completed. Thirdly, the actuator and output workspaces are mapped. Finally, some attractive characteristics of the mechanism are concluded. 1. Introduction As the complexity of robotic applications in space increases, new demands for lighter and quicker mechanisms arise. Tensegrity mechanisms can be viewed as one alternative solution to conventional mechanisms. For this reason, a planar 4-bar tensegrity mechanism is proposed in this paper and the kinematics and statics of the mechanism are studied. The term tensegrity was created by Fuller [1] as a combination of the words tensional and integrity. It seems that he was inspired by some novel sculptures completed by Snelson [2]. The detailed history of tensegrity systems was reviewed by Motro [3]. Tensegrity systems are formed by a set of compressive components and tensile components. Tensegrity systems have advantages of light weight, deployability, being easily tunable, and so forth. Due to these attractive characteristics, tensegrity systems have been used in several disciplines such as architecture, biology, aerospace, mechanics, and robotics during the last fifty years [4]. The applications of tensegrity systems can be divided into two main branches. One application is used as structures and the other one is used as mechanisms. In addition, the research of tensegrity structures has two main issues, which are the form-finding problem and the behaviors under external loads. The form finding of a tensegrity structure corresponds to the computation of the structure¡¯s equilibrium shape for a given set of parameters. This problem has been studied by many authors [5¨C7]. Moreover, a review of form-finding methods is given by Tibert and Pellegrino [5]. The behaviors of tensegrity structures under external loads have also been researched by many researchers [8, 9]. A static analysis of tensegrity structures was given by Juan and Mirats Tur [10]. When some components (rigid rods or springs) are actuated, tensegrity mechanisms
%U http://www.hindawi.com/journals/jr/2014/967251/