| The research on humanoid robot developed rapidly in recent years, and humanoid robot has more and more human being characters. Comparing with other locomotion methods, the supporting foot is alternately discretely contact with the ground during bipedal walking, the best supporting position can be chosen, the locomotion has the least restriction from the environment, so the bipedal walking has the highest flexibility. Since humanoid robot copy the locomotion method from human being, it suits to human-friendly help people or cooperate with people in the daily life and works. Studying the bipedal dynamical walking of a humanoid robot is becoming one of the main focus in robotics, it has not only important academic value but also considerable significance of application. To realize stable dynamic-walking involves many aspect, this paper studied the most fundamental ones of them, such as: the mathematical model, the stability constraints, gait planning and optimization, the control strategy of walking and so on. The researches include:1, The kinetics of a biped robot is expressed as exponent product using screw theory. The 3D analytic kinetic and dynamical models are deduced. The corresponding computer-aided symbol deduction program is compiled. Based on the knowledge of geometry and gait planning, the constrain condition of the stair acting on the robot walking path during climbing upstairs and downstairs is studied.2, For indicating the contact state between the supporting foot and the ground, the new concept of the center of the normal ground reaction force is introduced. Analyzing the distribution of the normal ground reaction force, the constraint condition of keeping the supporting foot to be fully in contact with the ground is obtained. The study shows cutting a slot at the bottom of the supporting foot can improve the contact state between the supporting foot and the ground. The contact state changes along with the change of the forces on the supporting foot. Syntheses the contact and slipping factor, the condition of keeping the supporting foot to be fixed on the ground is found.3, The common concepts of bipedal walking are summarized, the stability index and stability angle is proposed. The difference between single step and double step is cleared, and the "step " concept in humanoid robot and daily life is united. For utilize the inertia of the bipedal walking of the robot, taking the character of the main mass of the robot located at the upper-body in consideration, using the inherence trajectory of the inverse pendulum plans the walking gait. Under the circumstance of smoothly connecting deference gait of several phases, the forward gaits of the beginning and ending phases are designed in accelerating space. In consider the similarity of the lateral gait in deferent phases, the lateral gait of the beginning and ending phases are obtained from the middle phase using transition function. The modern Lie Group analysis is introduced, applying the Lie method of the invariance of the differential equations undergoing infinitesimal transformation, the Lie symmetry of the lateral dynamic model of the humanoid robot is studied, and the corresponding conserved quantity is found.4, Non-time reference gait planning method is proposed. The usual reference variable, time, is changed to a non-time variable in gait, so the whole gait-planning phase can be divided into two phases, (1) planning the space walking path: Taking the...
|
PDF Full Text Request