为了克服传统直线式土槽试验台的缺点,提出了旋转式圆形土槽试验台的总体设计方案;为补偿大尺寸圆形土槽加工、装配误差和方便后续配合农业机械的模拟田间试验,设计了轮胎摩擦驱动的旋转式圆形土槽试验台的初始安装位置机械式调整装置,并计算了土槽不圆度补偿能力;设计了土槽试验台控制系统,建立以PLC为主控、伺服电机为执行机构的闭环系统,使得该土槽具有平稳的运行速度;经试验发现该试验台能够补偿土槽的不圆度,可以在0-3.8 r/min转速范围内平稳运转,最大速度波动标准差为0.038 r/min,从启动到进入平稳运行所需最长时间为9.8 s;配合栽植机构进行移栽试验,株距变异系数为4.46%,均匀性好,能够满足移栽农艺要求。
In order to overcome the shortcomings of traditional linear soil-bin test bed,a kind of rotary round soil-bin test bed was proposed. To compensate the processing and assembly errors of the large-size round soil-bin test bed and provide convenience for the following simulating field trials of agricultural machinery,a driving scheme of rotary round soil-bin test bed driven by tire friction was optimized.Mechanical adjusting device for initial installation position of the rotary round soil-bin test bed driven by tire friction was designed,and the soil-bin roundness compensation capability was calculated. The control system for the proposed rotary round soil-bin test bed was designed,and the closed-loop system was established with PLC as controlling unit and servomotor as executive device. All of these made the soilbin test bed run at a steady speed; it was found that the test bed can compensate for roundness of soilbin,it can smoothly run at the speed of 0 - 3. 8 r / min,the maximum standard deviation of speed fluctuation was 0. 038 r / min,the longest time required from the start to smooth running was 9. 8 s.Transplant experiment with planting mechanism was carried out; the spacing coefficient of variation was4. 46% which means good uniformity and can well meet the transplanting agronomic requirements.