Differential End Force Of Two Arms Based On Perfect Internal Force Modeling And Control Research

Along with the development of science and technology and green manufacturing,the low-energy and compliance coordination operation of dual-arm robots has gradually become a hotspot of current research.The modeling and control of dual-arm robots,as the essence of dual-arm compliance coordination operations,have become a top priority in research.At present,the traditional dual-arm dynamics model is only the simple superposition of two single-arm dynamics,and the relationship between the two arms has not been established.The generalized inverse analysis of the dynamic model shows that the internal force model and the operating force model are intersected.Thus,the coordinated control based on this will cause energy loss of the robot arm,even cause damage to the object or the robot arm.Aiming at the above problems,based on the relative Jacobian matrix,this paper derives the differential end force dynamic model of the dual-arm,and establishes the relationship between the two arms.Based on the principle of equilibrium force,the reason for the cross of the internal force model is pointed out and perfected.And the differential end force dynamic model of the two-arm after optimization of internal force is obtained.Finally,the adaptive impedance compliant coordinated control based on this model is carried out.The main research contents are as follows:First,the differential end force dynamic model of the dual-arm.Based on the D-H parameter method,the coordinate system of each link of the two arms is established,and the Jacobian matrix of a single-arm is derived through the kinematics derivative method and the vector analysis method.The relative Jacobian matrix of dual-arm is obtained by using the translation and rotation matrix transformation relationship among the joints.Using the relationship between Jacobian matrix and the relative Jacobian matrix of the dual-arm,the differential end force dynamic model of the dual-arm is established by combining the virtual work method.Secondly,the differential end force dynamic model of the dual-arm based on the perfect internal force.Deeply analyzing the generalized inverse theory,the generalized inverse expressions in dynamic models under different circumstances are listed.The imperfection of the dual-arm end force model based on minimum norm decomposition is analyzed based on the principle of equilibrium force system.By selecting the appropriate dual-arm Jacobian generalized inverse to improve the two-arm relative Jacobian,the operating force term and the internal force term in the model are drawn and applied to the differential end force dynamic model of the dual-arm.Thirdly,an adaptive impedance compliance control system based on the differential end force model of the dual-arm based on the internal force load distribution.The impedance coordinated control system is used to improve the robustness of the dual-arm robot and solve the interactive problem between the dual-arm robot and the external environment.For the defect that the impedance coefficient of the system cannot be adjusted in real time,an adaptive term is introduced to improve the environmental adaptability of the dual-arm robot.And the stability of the system is proved by constructing and analyzing the Lyapunov equation.Finally,the simulation and experiment based on the differential end force model of the dual-arm which internal force is consummated.By selecting the structure data of robot arms and their joint motion parameters,the movement trajectory of the mechanical arms is determined.Based on the MATLAB software,the differential relative force and moment data of the dual-arm's ends with or without internal force load distribution are extracted,and the obtained curve is compared with the actual value.The analysis shows that the two curves have the same change trend.And the dual-arm differential relative end force based on the internal force load distribution is more accurate when a certain end force is required.Thus it can be seen,the model is more accurate and more perfect.