| 摘要: |
| 【目的】分析农用柔性底盘偏置转向机构工作参数对其运动与动力性能的影响，为柔性底盘转向控制提供依据。【方法】基于转向理论，以电动轮转速与载荷为因素，利用模糊综合评价法，用柔性底盘偏置转向时纵、横向驱动力及偏置臂转角相对误差构建综合指标，通过柔性底盘试验台测试二者对综合指标的影响，分析电磁摩擦锁锁紧电压与转向电桥步进电机转速对各个转向性能指标的单因素作用，并以转向内、外侧锁紧电压和步进电机转速为因素，通过L16(45)正交试验，探讨两侧偏置转向机构参数的分配特性。【结果】电动轮转速、载荷及交互作用对综合转向性能均有显著影响（P<0.05），电动轮转速为120 r/min左右时综合转向指标最小；随着锁紧电压及步进电机转速的增大，纵、横向驱动力均随之增大，而转角相对误差随锁紧电压上升先增大后减小，随步进电机转速增大而增大，锁紧电压与步进电机转速的适宜范围分别为18~24 V和150~180 r/min；转向内、外侧锁紧电压与步进电机转速对综合转向指标均有显著影响（P<0.05），空载时最优内、外侧锁紧电压分别为22 和20 V，最优步进电机转速分别为180和170 r/min，额定载荷时最优内、外侧锁紧电压分别为24 和22 V，最优步进电机转速仍分别为180和170 r/min；最优参数分配方案的验证试验表明，最优转向参数分配下柔性底盘偏置转向的纵、横向驱动力均有所提升且转向误差减小。【结论】优化试验所得转向内、外侧锁紧电压与步进电机转速组合可提升柔性底盘的综合转向性能。 |
| 关键词: 农业机械 柔性底盘 转向性能 工作参数 综合评价 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目（51375401） |
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| Experiment and optimization on working parameters of off-center steering mechanism for agricultural flexible chassis |
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QU Jiwei,GUO Kangquan,SONG Shujie,et al
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| Abstract: |
| 【Objective】This study analyzed the effects of off-center steering mechanism working parameters on the motion and dynamic performance of agricultural flexible chassis (FC) to provide basis for steering control of FC.【Method】Based on steering theory,the influences of speed of in wheel motor (IWM) and load of FC on longitudinal force, lateral force and steering relative errors were tested using self made test bench.Then,a comprehensive evaluation method was introduced to combine these three indicators into a comprehensive index (CI).The single factor effects of locking voltage (LV) and speed of stepper motor (SMS) on each indicator were also analyzed.Taking SMS and LV of the inner and the outer steering sides of FC as factors,a orthogonal test was designed and the influence of each factor on CI was analyzed.Finally,the optimal parameters distribution was obtained and verified by experiments.【Result】The speed of IWM,the load of FC and their interaction had significant effects on CI (P<0.05).The comprehensive index had the smallest value when the speed of IWM was around 120 r/min.With the increase of LV and SMS,both lateral force and longitudinal force increased steadily.The steering error increased first and then declined with the increase of LV,and it increased with the increase of SMS.The reasonable ranges of SMS and LV during steering were 150-180 r/min and 18-24 V,respectively.The inner LV,outer LV,inner SMS and outer SMS all had significant effect on CI (P<0.05).In the case of no load,the optimal inner and outer locking voltages were 22 and 20 V,and the optimum stepper motor speeds were 180 and 170 r/min,respectively.In the case of rated load,the optimal inner and outer locking voltages were 24 and 22 V,and the optimal stepper motor speeds were still 180 and 170 r/min,respectively.The verification showed that longitudinal and lateral driving forces of off center steering were increased and steering errors were reduced under the optimal steering parameters.【Conclusion】The combination of locking voltages and stepper motor speeds of the inner and outer steering sides obtained from this test improved the comprehensive steering performance of the flexible chassis. |
| Key words: agricultural machinery flexible chassis steering performance working parameters comprehensive evaluation |
