Single Leg Structure Design And Motion Modeling Analysis Of Quadruped Robot With Jumping Function

Quadruped mammals have many advantages,such as high speed,strong jumping ability and adaptability in complex environment.Quadruped bionic robots based on quadruped mammals have broad application prospects in many fields.In order to develop a high performance quadruped robot with fast moving speed,strong jumping ability and good adaptability to complex environment,this paper takes quadruped robots as the research object and studies it deeply.On the basis of theoretical calculation and simulation analysis,the bionic structure design of quadruped robot,the kinematics and dynamics analysis of the single leg and the key problems in the dynamic simulation are deeply analyzed and studied.On the basis of the existing quadruped robots,a novel quadruped robot single leg is designed.The single leg is set as a structure unit which can be controlled by the energy storage and change law.The specific structures of the hip joint,knee joint and energy storage device of the single leg are designed,and the functions of flexible damping and energy storage in the leg structure are studied.In order to study the kinematic characteristics of the jumping motion of the quadruped robot's single leg,the kinematic analysis of the jumping stage and touchdown stage was carried out respectively for the single leg motion.By analyzing and applying the D-H method,the kinematic positive solutions and inverse solutions of the jumping stage and touchdown stage are deduced for single leg movement,and the velocity and acceleration of the single leg are further analyzed.By using MATLAB software,the motion working space of the single leg is obtained.Finally,the statics of the quadruped robot's single leg is analyzed,and the mathematical model of the positive and inverse analysis of the statics is established for the robot's single leg.In order to study the dynamic characteristics of the jumping motion of the quadruped robot's single leg,the whole process dynamic of quadruped robot's single leg motion is analyzed.Because the force of robot's single leg jumping stage and touchdown stage are different,the dynamics of robot's single leg is divided into two stages.In the jumping stage,the dynamic analysis model of multi rigid body system is set up.The relative kinematics is analyzed for the robot's single leg,the dynamic equation of the single leg jumping stage is established by using the Lagrange method,and the related solution is carried out.At the moment of the end of the jumping stage,the foot of the robot's single leg has an impact on the ground,and the dynamic model of the landing impact is established for the single leg.The motion is analyzed and solved after robot's single leg landing impact,the motion energy loss of the robot's single leg is also obtained.In the touchdown stage,the robot's foot contacts with the ground,and the size of the damping spring has large deformation in the shank.In this stage,the robot's single leg is regarded as a rigid-flexible coupling system,and a dynamic analysis model of rigid-flexible coupling is established.The dynamic equation of this stage is established by using Lagrange method,and solved.The analysis results laid a theoretical foundation for robot jumping control.In order to verify the rationality and the motion effect of jumping motion of the quadruped robot's single leg,the trajectory planning is carried out for the single leg vertical jump motion in four stages.A realize jumping effective method is planned for the robot's single leg.The five curves are used for the trajectory planning in the rise and take-off stage and the descending touchdown stage,which effectively avoids the discontinuity of acceleration.Combined with theoretical analysis,virtual prototyping technology is applied to simulate the dynamic process of robot's single leg mo tion.The three-dimensional model is imported into the ADAMS software to simulate and observe the movement of each component.The displacement,speed and acceleration curves of each component and its joint are obtained in ADAMS.The force situation and simulation effect of each component are analyzed in jumping,and it's dynamic performance is evaluated.Thus,the robot control,optimization design and path control simulation can be realized,and the jumping ability of the robot is improved.The simulation results provide a reference for robot motion control.