Synthesis Theory Of Straight-line Track Linkages And Development Of Its Software System

Straight-line trajectory linkage mechanism plays an important role in straight-line motion mechanism.Researchers have given many classical comprehensive theories and methods through in-depth research,and established a mature comprehensive theoretical system.However,with the continuous progress of science and technology,robotics,aerospace,medical,transportation and other fields continue to develop in the direction of automation,high-speed,high-precision,and put forward higher and higher requirements for the synthesis accuracy and efficiency of linear linkage mechanism.For this reason,Researchers at home and abroad have put forward many new synthetie methods and solved many comprehensive problems by combining theoretical methods with analytical software.but these methods still have the problems of low comprehensive efficiency and wide application range.The previous synthesis methods can not meet the requirements of the development of modern machinery.Therefore,In order to keep up with the development of modern machinery,it is particularly important to study the theory and method of linear trajectory synthesis of linkage mechanism and develop the synthesis software.In view of the above background,this paper focuses on the synthesis of straight-line trajectory of linkage mechanism,and mainly studies the following aspects:(1)In this paper,aiming at the synthesis of four-position straight-line trajectory of planar four-bar mechanism,the Ball point theory and its synthesis formula are used to derive the synthesis software,and the solution-region diagram of the mechanism is obtained.the trajectory synthesis method of five-point straight-line linkage mechanism under general and special conditions is studied by using the theory of Burmester point.Using analysis software,the performance solution-region maps including the ratio of rod length,rod length and mechanism type are drawn.The specific information of the mechanism can be intuitively understood in the solution-region diagram,which effectively avoids the blindness in selecting the mechanism and improves the synthesis efficiency.(2)In this paper,aiming at the synthesis of two-line trajectory of planar four-bar mechanism,based on the synthesis of single-linetrajectory of planar four-bar mechanism,the synthesis of double linear trajectory of crank-rocker mechanism is studied,and the specific synthesis method is given.Taking the number of double Bauer points as variables and using the developed comprehensive software,the solution domain diagram of the distribution law of the number of double Bauer points is obtained,which enriches the theory of double-line synthesis of planar four-bar mechanism.(3)In this paper the straight-line trajectory linkage mechanisms with special positions are studied,and the comprehensive formulas of these mechanisms are derived.The straight-line trajectories of these special mechanisms are synthesized by using comprehensive software,and the specific analytical formulas for the kinematic analysis of four-bar mechanisms are deduced.The comprehensive software is developed,and the kinematic curves of each point on the planar four-bar mechanism are obtained.