针对农业机械滑动耕作部件(如深松铲、起垄铲等)田间作业时阻力采集困难和相关阻力测试装置结构复杂、维护使用成本高、缺乏过载保护等问题,设计了一种滑动式耕作部件作业阻力测试装置(TRTD)。TRTD包括部件安装库、扭转弹簧、旋转主轴、定位盘和编码器等,并以双翼型深松铲为例,建立了包含修正系数k与扭簧转角θ、耕深H、耕速v、土壤容积密度ρ、深松铲结构参数等换算关系的耕作阻力测试方法,与传统三点式作业阻力测试系统(TTD)在6组耕作条件下进行了土槽对比试验。试验通过F检验和T检验(α=0.05)得出2种测试装置测量值总体方差相同和均值一致。精度分析结果表明TRTD相比于TTD的最大相对误差为1.34%,波动性分析结果表明TRTD与TTD的波动幅值比较接近,两者最大相对偏差都不超过5%。TRTD满足阻力测试装置的精度和稳定性要求,能保证作业阻力采集的同时,具有过载保护功能。
Accurate measurement of tillage resistance for cultivate component is critical.The related resistance testing device has complex structure,high maintenance cost,lack of overload protection and difficulty in collection in farmland.Aiming at the problems of the related resistance testing device,the tillage resistance testing device(TRTD) for sliding cultivate component was designed.TRTD consisted of component library,torsional spring,rotation axis,positioning plate and encoder.The force analysis of double-wings subsoiler was carried out.A measurement method of tillage resistance was established which contained the relationship of correction factor k as a function of spring corner θ,tilling depth H,tilling speed v,soil bulk density ρ and subsoiler structure parameters.In order to evaluate the TRTD,a soil bin contrast test with traditional testing device(TTD) was conducted under six tillage condition treatments.The test results showed that the mean and variance of the measured sample from both testing devices had no significant difference.The results of precision analysis showed that the maximum relative error of TRTD was 1.34% compared with TTD.The results of fluctuation analysis showed that the fluctuation amplitude of TRTD was similar with that of TTD and both relative deviations were not more than 5%.TRTD met the requirement of accuracy and stability and possessed the function of overload protection as well as providing condition for acquisition of tillage resistance.