Design And Analysis Of A Kind Wheel-Tracked Composite Variant Wheel

Research institutes of every country attach more and more importance to the research ofall-terrain mobile chassis in case of non-structural complex and changing environment. It hassignificant research and application value for flexibility and trafficability of vehicles andmobile robots. Wheel-tracked variant wheel is composed by reconfigurable track, strechingmechanism, transmission mechanism and driving mechanism. The wheel alternates between“cirle” and “triangle” by driving internal streching mechanism, thereby improving athleticperformance of mobile chassis. When variant wheel runs on the good road, it can go well andquickly as with the wheeled chassis saving time. The variant wheel is turned into “triangle”When it encounters intertidal zone, gully ice and snow. After passing obstacles, in can go backto wheeled chassis and continue to run. This variant wheel has some advantages such ascompact structures, terrain adaptable and high operating efficiency.Firstly, the advantages and disadvantages as well as the applicable environments andsituations of the wheeled, the tracked and the wheel-tracked walking mechanism in domesticand foreign are analyzed. Then the design ideas of variant wheel is put forward combinedwith practical needs. The operating principle and design scheme of variant wheel is analyzedin detail. Mainly includes wheel deformation principles and programs; reconfigurable track’sshape, structure, and material elongation; programs analysis of transmission mechanism’sstructure and power transmission; planning motion curve of streching mechanism’s stretchingand contraction, contrast-driven solutions and selection of the hydraulic cylinder, strengthcheck, the construction of hydraulic circuit and control.In the next, the key points of design are proposed and detailed designing of themechanical structure on variant wheel. With SolidWorks software to establish thethree-dimensional model of the variant wheel, and estimating the quality, checkinginterference, etc. With the ANSYS finite element simulation software to analyze stress-strain,check strength and optimize structure of the track, the leaf spring and streching mechanism,which are the key component parts of variant wheel. Then, generating engineering drawingsand trial-manufacturing model machine.At last, as the manufacture of the variant wheel is completed, independent load tests areconducted by the INSTRON loading machine for the key components of the variant wheelsuch as the track and the leaf spring. Then, draw the motion trail of the stretching mechanismof the assembled variant wheel and measure the stretching rate of the reconfigurable tracked.After that, install the assembled variant wheel on the ATV four wheel drive sport utilityvehicle to carry out related tests. So, some related parameters such as the maximum runningspeed of the round state and the obstacle climbing ability of the triangular state of thewheel-tracked variant wheel can be measured. It turned out that the track and the leaf spring meet the design requirements. To prevent the track from swinging around, the speed of theround state can’t beyond25km/h. As it turned into the triangular state, it has the ability ofclimbing the slope with the angle of28degrees，the boss with the height of180millimetersand the ravine with the width of400millimeters.Conclusion: Wheel-tracked variant wheel can stretch and recovery and normallyoperation between two kinds of working condition. By which，proved the structural design isreasonable and reached preliminary first-generation prototype design requirements. In thenext study, we need to make an intensive study of variant weight, the height of climbing bossand the problem of “tossing band” in wheel state.