Research On Adaptive Planetary Wheeled Crawler Robot

With the continuous innovation and application of technology,all kinds of ground moving mechanism have more superior performance.Among them,crawler mobile mechanism is widely used because of its large ground area,small ground specific pressure,strong adaptability to the environment,and good movement ability in various complex ground,especially in military investigation,post-disaster search and rescue and other fields,crawler mobile mechanism has superior performance.According to the characteristics of the crawler mobile mechanism,this paper proposes an under-driven planetary wheeled crawler mobile mechanism to extend the range,improve the robot's passive obstacle crossing ability and reduce the obstacle crossing time.Based on the investigation of the research status of crawler mobile mechanism at home and abroad,this paper compares and analyzes the characteristics of various crawler mobile mechanism.According to these characteristics,a planetary crawler type auxiliary obstacle crossing mechanism with under-drive and passive self-adaptation is proposed,which can make the robot move in different forms according to the change of terrain conditions.By comparing the characteristics of different arrangement schemes of the star-shaped crawler mechanism on the robot chassis,a optimal arrangement scheme with a forward swing arm is selected.The kinematics and dynamics models of the crawler mobile platform on the horizontal ground are established and the movement characteristics of the crawler robot on the horizontal ground are analyzed.In this paper,the obstacle crossing performance of planetary crawler wheel under different driving conditions is analyzed,and the motor torque required by the robot when climbing the stair obstacle is calculated by establishing the dynamic model,and the motor torque required by the robot when climbing the slope,crossing the ditch and other obstacles is calculated and analyzed.The multi-body dynamics simulation software RecurDyn was used to create a virtual model of planetary wheeled crawler robot,and the torque curve of the robot driving the wheel in the process of moving on slope,trench and step terrains was obtained.To the results of theoretical calculation and simulation analysis of mutual authentication,on the basis of contact with the actual situation to determine the structure parameters of the robot,and using SolidWorks software to the design of the various components in detail,using the finite element analysis software for the design of the robot's key has carried on the intensity of bearing parts,the structure of the robot is optimized according to the results of the check.After the overall design of the crawler robot is completed,a prototype robot is trial-produced and tested on flat land,grassland and rugged terrain.In particular,the robot climbed stairs and crossed ditches through experiments,which verified the correctness of theoretical analysis,the adaptability of underdriven planetary crawler wheel to terrain and the robot's strong ability to climb steps.The innovation of this paper is that the underactuated planetary crawler wheel is applied to the crawler robot,which reduces the number of motors driving the robot and the weight of the robot.This enables the robot to have better obstacle jump and endurance,and the passive adaptive terrain enables the robot to jump over obstacles more quickly.