Analysis And Control About Rolling Motion Of Spherical Tensegrity Robot

The spherical tensegrity structure consists of 6 bars and 24 strings which are connected to each other,The strings only bear the tension and the bars only bear the pressure.Because its appearance is similar to the sphere,it is called the spherical tensegrity structure.At first,the tensegrity structure appeared in the art field only in the form of sculpture,then gradually it formed a certain research system,more as a new kind of spatial structure appeared in the field of architecture.At the end of the 20 th century,researchers applied the tensegrity structure to the field of biology and made outstanding contributions.In recent years,the tensegrity structure has been applied to the field of robot.By controlling the length or force of the string,the whole structure can complete the specific motion according to a certain rule.In this paper,the spherical tensegrity robot is taken as the main research object.Firstly,I complete the shape finding of the robot,establish it's dynamic model and analyze the principle of robot motion.Secondly I obtain the relationship between the rolling direction and the length of the string of the robot and use the genetic algorithm to optimize the rolling gait.Then I complete the “manual” control,the simulation of rolling direction control of the robot.At last,I complete the manufacture and continuous rolling verification of the robot prototype.The main contents of this paper are as follows:This subject first describes spherical tensegrity structure,studies its structure topological relations,uses the method of solving the nonlinear equations to complete the shape finding of the spherical tensegrity structure and establish the dynamic model of the robot.In this paper,the concept of heavy torque is used as a static method to judge if the robot can rool.Secondly,the concept of rolling gait is put forward and classified according to the topological relation of structure of the robot.When the length of string changes,the whole shape of the robot will change,so the relation between rolling direction and length of string element should be obtained.The rolling gait is optimized by genetic algorithm under the condition of different number of driving.Then,the "manual" control of the robot can be realized by the relationship between the rolling direction and the length of the string.The look-up table algorithm is constructed and applied to the robot's rolling direction control system to complete its directional control simulation.Finally,it's necessary to complete the manufacture of the prototype,including the driving mode,the electronic control system and the structure design.In addition,the experimental verification of the continuous rolling of the robot is also needed.