Analysis Of Quasi-static Locomotion And Obstacle Climbing Capability Of Rolling Mechanism Based On Close Chain Five-bow-shaped-bar Linkage

Along with the progress of technology, mankind is looking for better ways to instead ofthe human being with extensive labour and research the outer space that unknown. Now,moving mechanism is utilized in producing, living, research, military more widely. The legrobot is stablely and can adapt to the unstructured environments where the terrain is irregularand plain alternately, but less efficient with slow speed, but rolling mechanism can passsmoothly structured environment stably, greater speed and more energy efficient. The movingmechanism is required to have new rolling robot. According to the theory of body bionics,Rolling Mechanism Based on Close Chain Five-Bow-Shaped-Bar linkage is put forwardbased on the summary of the latest research results at home and abroad. Through coordinatedjoint movements during the rolling mode, the rolling movement is driven by the gravitationaltorque of the centroid offset that is caused by slowly moving the robot’s center of gravityfrom its geometric center to achieve rolling and obstacle claiming.Firstly, The structure is designed in this paper, the bow-shaped-bar structure isintroduced into a rolling robot, The robot has a modular structure. Which is made up of thebody. And the structure is designed based on the symmetry theory. Mass center distributionand the structure parameters of limbs and trunk are designed according to the rotationalsymmetry principle, and also take use of the pro/engineer to optimize the parameters of thestructure, stimulating hao it achieves rolling. Also use dynamic stimulus to evaluate the torqueof the motor.Secondly, the rolling mechanism is simplified, kinematic model of quasi-staticlocomotion process is established. The mobile strategy for Centroid is put forward; thetermination robot configuration is optimized through penalty function. According to thenonlinear characteristics of the kinematic equations, joint trajectory is planned by the leastsquare method based on the principle of less energy consumption.Once more, the rolling robot is simplified when closed chain five-bar linkage whenrolling on the flat surface. The segmentation functions are utilized to derivate the kinematicconstraint equations and the center of mass trajectory equations during a rolling cycle, as wellas the center of mass motion velocity and acceleration equations.Based on the summary of thedeficiencies in the existing rolling institutional trajectory planning, the constant center ofmass offset joint trajectory planning strategy is put forward, as well as the precise conditionsof smooth motion and joint continuity. Joint trajectory is placed in a rolling cycle according to this strategy. The planning results to verify the correctness and rationality of the trajectoryplanning strategy, and also verify the superiority of the quadruped robot on the structure.Finally, we put forward three principles how the rolling robot achieves climbing. Howdifferent factor affects it, analysis the highest altitude the rolling robot can climb.The robotprototype is performed. Related experiments to verify the superiority of the rolling robot onthe structure.