Structure Synthesis And Performance Analysis Of Forging Manipulators

Forging manipulators is one of essential forging equipments in the modern forging workshops,which is used to forge workpiece with foging press.Forging manipulators have advantages of liberating workers' productivity,enhancing the production efficiency,improving the working environment and realizing the automatic forging.Now the research level of domestic forging press has been at the forefront,however,the research of forging manipulator started late,and it can not reach the international advanced level,restricting the development of forging industry.Therefore,the paper takes the forging manipulator as the research object,carries on the thorough theory research from its structure synthesis,kinematics,dynamics,anti-toppling stability and bearing capacity.The basic module mechanisms and combination rules are established.Based on the combination rules,the transformation of the kinematic diagram of the mechanism to the combination graph was carried out.According to the corresponding relationship between the connection elements of the combination graph and the connection matrix,the digital representation of the combination graph is solved.Based on the relative links matrix of basic mechanisms,an identification method of the combination rigid structure is proposed.Based on the connection sequence and the combination principle of 2-link Barranov truss,an identification method of the combination isomorphism is proposed.Based on the identification methods of the combination rigid structure and isomorphism,the structure synthesis software of the major-motion mechanisms is developed.Through the constraint-synthesis method of screw theory two types of wrench systems of the lateral-translation and yawing mechanisms are obtained.Based on the two types of wrench systems,the limb wrench systems of three limbs and four limbs are obtained respectively.According to the limb transformation principle,the various lateral-translation and yawing mechanisms are obtained.The yawing characteristic of the second kind of the yawing mechanism is obtained on the base of the structural characteristic.Combined with the major-motion mechanisms,10 kinds of forging manipulators ate constructed.The motion algorithm module and flowchart are proposed.According to the vector relation of the parameters in the algorithm flowchart,the kinematics functions of the motion flowchart are obtained.Based on the kinematics functions the forward and inverse position kinematics of three major-motion mechanisms are analyzed.Meanwhile,the movement space,lifting deviation and other kinematics performances are obtained.The force algorithm module and flowchart are proposed.According to the Newton-Euler dynamics equation,the dynamics functions of the force flowchart are obtained.Based on the dynamics functions,given the clamp trajectory planning function,the driver forces of the three major-motion mechanisms are analyzed.A novel anti-toppling stability function is proposed.Based on the function the dynamic changes of anti-toppling stability of three main motion mechanisms during different movement are obtained.According proportional coefficient method of planar mechanism the dynamic changes of bearing capacity of three major-motion mechanisms are analyzed,when the pitching angle is-10,0 and 10 degrees.The scale model of the N-I forging manipulator is developed.The open loop hydraulic system is designed.The circuit control system of the hydraulic system is completed.The lifting,horizontal-translation,pitching,lateral-translation and yawing of the manipulator are shown.