Design And Performance Study Of The Rubber Crawler Combined With High-range Sprayer

Pest control was an important link to insure high yield of agroforestry. To improve thetechnical level of plant protection equipment applied to field-crops and tall trees, rubber crawlerself-walking type high-range sprayer was researched, which high-range spraying installation andrubber crawler successfully combined.The model of contacted pressure of caterpillar track was constructed with the simplifiedmodel method. The expressions of contacted pressure, adhesive force and driving force on levelroad and ramp were deduced. The results showed that the maximum distance between centre ofcontacted pressure and centre of ground connection was1/6length of ground connection. Besides,the best slip ratio was inexistent when the contacted pressure was the uniform distribution. But,the best slip ratio was existent when the contacted pressure was the nonlinear distribution.Main components of high-range sprayer were designed. Moving device was the four-wheelone-belt structure. The pitch of rubber pedrail was101mm. The length of ground connection was1.5m, the distance between two tracks of bilateral rubber pedrail was1.2m, the highest designspeed was6km/h. Integrated body frame was maked up by chassis and subframe, power ofdriving gear was9kW, power of the engine was25.4kW. In addition, various performances of thesprayer were acquired via analysis. Nominal contacted pressure was18.1kPa in the full-ladencase. The maximum permissible gradient was decided by the cohesion of soil. The width of ditchwhich was under0.94m could be successfully strided when the sprayer went ahead and the valuewas0.55m when the sprayer drew back. The ultimate angle of the upward gradient or thedownward gradient when the sprayer could berth safely respectively was33.7°and48.1°.The statics analysis, the modal anslysis and the optimal design of the integrated body framewere accomplished by ANSYS. The maximum equivalent stress in the frame which was in thefull-laden case or the empty-laden case respectively was90.1MPa and110.3MPa, and thecorresponding safety factor was2.61and2.13, which indicated that material was superfluous.The half dozen intrinsic frequency of the frame respectively was12.0Hz,14.5Hz,18.9Hz,23.7Hz,27.4Hz and33.3Hz. The highest sensitivity for the evaluation parameter was thethickness of material by the parametric design moudle. The superfluous condition of material wasacquired by the topological optimization moudle. And optimal design for the frame wasaccomplished which was based on the consequences of these two modules.The prototype of the high-range sprayer was applied in a series of experiments. Theexperiment results showed the first four intrinsic frequency respectively was54.7Hz,82.0Hz, 109.4Hz and165.0Hz, furthermore, these amplitudes of the time-field curves were stable. Themaximum coefficient of the static friction was0.20and the dynamic friction coefficient was0.18by the hauling experiment in the full-laden case. The linear regression model of the deviation ratewith respect to velocity, the minimum turning radius with respect to the turning angularvelocity were established which were based on experiments data.