Design And Movement Research Of The Wheel-Track-Leg Hybrid Mobile Robot

With the development of robot technology and the improvement of intelligence,robots have more sophisticated structure and advanced sensor technology.“Smart” robots can show their talents in all fields,and small ground mobile robots as intelligent special robots are widely used in military investigation,nuclear power testing,explosion warning and other fields with their structural characteristics and performance advantages.However,for the ground mobile robots,there are still many problems to be solved in practical applications.Long-term survival and stability in unstructured environments will be a huge challenge,especially when the robots are unable to avoid high obstacles or complex terrain,but to overcome the high obstacles and adapt to the complex terrain,so the high capability of obstacle negotiation and good adaptability becomes particularly important for the robots.Firstly,this paper summarizes the research results of wheel-track-leg hybrid mobile robot both at home and abroad,and learns lots of design experience from the excellent cases.For the unstructured environment,a new wheel-track-leg hybrid mobile robot has been proposed,which is composed of a robot body,four driving mechanisms,four independent track arms,two supporting legs and one wheel lifting mechanism,and the robot can fully benefit the advantages from wheeled,tracked and legged mobile robots to move in the hybrid locomotion mode for the rough terrain and high obstacle.Secondly,based on the principle of dynamic pose transformation matrix,the kinematics model of center of mass of the robot and the kinetic equations of the robot system have been established.For unique structures of the front and rear support legs of the robot,a new method of obstacle negotiation based on track-leg mode in unstructured environments has been presented.Meanwhile,the constraints and nonlinear relationship model when crossing obstacles have been solved.Moreover,the method of stability pyramid also has been used in the analysis of climbing motion,especially in the hybrid locomotion mode,it's proven that the robot can remain stable in the process of climbing motion.Thirdly,based on Altium Designer software,the robot hardware control system is designed,and the system is based on the microcontroller including power conversion,drive,communication and other peripheral circuits,and wo generations of hardware circuit boards are welded and debugged.Finally,based on Solidworks 3D modeling,simulation experiments and prototype experiments are carried out to verify the feasibility of the scheme.