Dynamics Modeling And Gait Planning Studies Of Biped Robot With Heterogeneous Legs

This paper proposes a new mode of humanoid robots-Biped Robot with Heterogeneous Legs (BRHL), in order to improving personification features of humanoid robot walking and providing ideal research platform for intelligent prosthetic, etc. BRHL is the integration of legs walking robot and intelligent prosthesis research. It can simulate the situation that the disabled wear intelligent prosthetics very well. The artificial legs correspond to the disabled healthy leg, and the bionic legs correspond to intelligent prosthetic leg which the disabled wear. Based on BRHL as research platform, the works done in this paper is as follows:The research status of humanoid robot and intelligent prosthesis at home and abroad has been elaborated, and the design project has been proposed. BRHL hip joint has three degrees of freedom, which is driven by a motor, legs knee has been used four-bar closed chain. The artificial legs knee joint is driven by artificial muscle active, and the bionic legs knee joint is driven by semi-active magneto rheological damper.On the basis of the purpose of BRHL kinematics modeling and methods expounded, the position of the robot has been analyzed, the constraints problems of knee joint four-bar linkage has been discussed. Based on the homogeneous coordinate transformation, BRHL kinematics model has been deduced. In addition, based on first class Lagrange dynamics equation and the thought of segmentation modeling, first, dynamic model of artificial legs and bionic legs has been established in the support phase and swing phase. Then, the coordination dynamics model of BRHL has been presented. The modeling method can conveniently analysis the driving moment of each joint requiring.Based on the method of Human walking motion data to do gait planning for artificial legs of the robot, it can determine existing constraints in the gait process. By solving the inverse kinematics to get the angle of the key points, then this paper uses interpolation function of cubic spline to critical point interpolation and calculates the movement trajectory curve of each joint of the robot. Finally, this paper uses the idea of gait follow to conduct followed gait optimization for the bionic leg. Following results prove that the method is feasible and effective. Based on the virtual prototype technology, the three-dimensional model of simplify BRHL has been established in Pro/e software. Through importing it into the ADAMS software, the Walking movement has been simulated, so as to validate the result of the gait planning.Finally, this paper summarizes the work, analyzes shortcomings and proposes future research priorities.