| The tensegrity robot has many characteristics,such as its light weight and strong flexibility,so that it can keep its original shape and not be destroyed when it is thrown to the ground at high altitude.The good expansion ratio of tensegrity robot makes it a research hotspot in the field of space exploration.Among many robots,the six bar spherical tensegrity robot has the characteristics of high structural symmetry,simple control and strong carrying capacity.In this paper,the original six bar spherical tensegrity robot is debugged,the factors affecting the robot motion are analyzed,and the scheme of designing electric cylinder to solve the robot motion failure is proposed;According to the designed electric cylinder,a new tensegrity robot is built.The specific research contents are as follows:1.The mathematical model of the six bar spherical tensegrity structure is established,and the relationship between the length and force density of the bar member and the cable member is determined through the node balance;The motion of the original robot is debugged,and the motion limiting factors of the robot are summarized;An electric cylinder with small structure,fast movement speed and large thrust is proposed to optimize the structure of the robot and make it realize the expected movement;According to the design requirements,select a reasonable transmission scheme,select the lead screw and motor in the electric cylinder,check the strength of the lead screw,and complete the overall structural design of the electric cylinder.2.The dynamic simulation of the electric cylinder is carried out to verify whether its motion speed and displacement meet the theoretical setting values;The impact load of the electric cylinder is simulated to verify whether the structural stiffness can meet the actual requirements;Carry out finite element analysis on some parts of the electric cylinder to verify whether the strength of the structure meets the actual requirements;Explore the installation position of the controller in the robot,determine the best installation mode of the controller,and determine a reasonable signal transmission mode for this installation mode;Select the controller of the robot,reasonably arrange each control element according to the principle of minimum push rod structure,and draw and make relevant PCB circuit boards.3.This paper explores the static slope of the robot,analyzes the maximum slope value that the robot can maintain stability when it lands on the slope with different positions and postures,and calculates the corresponding slope value through theory;Finally,the correctness of the theoretical calculation is verified by the dynamics software,and the causes of the error are analyzed.4.Assemble the parts and controller,and build the physical model of the electric cylinder;Build an electric cylinder test bench to test its thrust,speed and current;When the voltage is constant,the thrust and speed,thrust and current of the push rod are measured,and the relevant laws are summarized.Under the same thrust,the relationship between the push rod speed and voltage is inferred;Select the reasonable parameters of electric cylinder and spring stiffness coefficient to build the optimized tensegrity robot;According to the rolling mode of the robot,the upper computer App controlling the robot is designed;The robot feedback mechanism is added to determine the number of the robot landing push rod through the feedback mechanism and then control its motion;The robot is tested to determine that it can achieve the expected gait movement. |
