Papers by Author: Yi Cao

Abstract: This paper mainly addressed the workspace analysis and performance evaluation of a special class of the 6/6 cable-suspended parallel robot. Based on the screw theory and the static equilibrium, the Jacobian matrix of the cable -suspended parallel robot is constructed. The workspace volume is characterized as the set of points where the centroid of the moving platform can reach with tensions in all suspension cables for a constant orientation. This paper attempts to tackle some aspects of optimal design of this special class of the 6/6 cable-suspended parallel robot by addressing the variations of the workspace volume and the accuracy of the robot using different geometric configurations, different ratios and orientations of the moving platform. The global condition index is used as a performance index of a robot with respect to the force and velocity transmission over the whole workspace.

Abstract: masticatory movement of mankind is a very complicated process of food processing. In order to research the mechanism of masticatory,firstly, a bionic robot must be designed to achieve chin’s multi-degree of freedom motion and chewing. By 3/3-RRRS parallel mechanism driving teeth up and down, it achieved full chewing of food. The study of this article is done in the condition of each given attitude and location of the moving platform, using the method of the three dimensional boundary search for location workspace. Through the research on workspace, it can be used to analyze the change law of workspace, and provide a theoretical basis for chewing bionic robot’s design with specific chewing campaign parameters.

Abstract: It is known that two primary disadvantages of parallel manipulators are the complicated forward kinematics and limited workspace. This paper mainly addressed the kinematics and workspace analyses of a 3/3-RRRS 6-DOF parallel manipulator. After a brief introduction of the 3/3 -RRRS 6-DOF parallel manipulator, a three-dimensional model and its relevant structure diagram are constituted, the forward and inverse displacement analyses of the 3/3-RRRS parallel manipulator are discussed in detail, especially, a novel geometrical method referred as equivalent mechanism is proposed for the forward displacement analysis of the manipulator under consideration. Based on the displacement analyses of the manipulator, a discretization method is proposed for the computation of the reachable position/orientation workspace of the 3/3-RRRS parallel manipulator, respectively. Examples of a 3/3-RRRS parallel manipulator are given to demonstrate these theoretical results.

Abstract: This paper mainly addressed the kinematics simulation of the Slider-Crank mechanism. After proposing a mathematical model for the forward displacement of the slider-crank mechanism, the mathematical models for the forward velocity and acceleration of the slider-crank mechanism are constructed, respectively and the simulation models for the forward kinematics of the slider-crank mechanism are constituted in the Matlab/Simulink simulation platform. Finally the forward kinematics simulation of the slider-crank mechanism was successfully accomplished based on Matlab/Simulink. Examples of the simulation for the forward kinematics of a slider-crank mechanism are given to demonstrate the above-mentioned theoretical results.

Abstract: This paper introduced the important role of the remote sensing satellite in remote sensing field. There existed some defects for a traditional classical AZ-EL type antenna used in tracking remote sensing satellite. The design project of Stewart manipulator antenna was presented by Stewart manipulator designing theory. The singular configuration theory of Stewart manipulator introduced position singularity, attitude singularity analysis and posture ability of Stewart manipulator was studied. The theorem of nonsingular posture was presented and proved. The nonsingular workspace area of a Stewart manipulator was determined. The antenna design based on Stewart manipulator satisfied with hemisphere airspace workspace and got the theoretical basis of realizing passing zenith tracing.