农用底盘主动平衡试验平台与控制系统设计与试验  

Design and Experiment on Auto Leveling System and Control Strategy for Agricultural Chassis

作　　者：赵建柱[1] 高明远 马晨旭 王志策 黄莹 黄韶炯[1] ZHAO Jianzhu;GAO Mingyuan;MA Chenxu;WANG Zhice;HUANG Ying;HUANG Shaojiong(College of Engineering,China Agricultural University,Beijing 100083,China)

机构地区：[1]中国农业大学工学院,北京100083

出　　处：《农业机械学报》2018年第11期358-364,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家重点研发计划项目(2016YFD0701705)

摘　　要：常规的农用作业装备很难适应坡地作业环境,为了使作业车身在坡地作业时保持水平,以主动平衡系统作为研究对象,开发了主动平衡试验平台及控制系统。基于Sim Mechanics与Sim Hdraulics模块建立了机-电-液多物理域仿真模型;针对双作用非对称式液压油缸推程与回程运动的不同特性,采用双通道式PID控制策略进行控制,分别对液压油缸跟随响应、位移误差变化、速度阶跃响应与平台双轴倾角进行仿真分析。仿真表明,双通道PID控制下最大跟随误差为1. 90 mm,响应时间为0. 228 s,极限状态下平衡时间为2. 98 s。与单通道PID控制相比,其最大控制误差降低49. 3%,响应速度提高了45. 8%。在实验室模拟8种不同坡度,对主动平衡试验平台进行响应时间和平衡效果测试,系统响应时间为0. 328 s;随着坡度的增加,试验平台调平最大误差为1. 14°,最大均方根误差为0. 299°,主动平衡试验平台及控制系统达到了设计要求。Conventional agricultural chassis was difficult to adapt to the slope which put a severe test during the operation.Taking the auto leveling system as the research content,a two-degree of freedom platform and its self-control system was developed.The mechanical-electrical-hydraulic multi-physics simulation model was established based on SimMechanics and SimHdraulics,which helped to analyze spatial kinematics through SimMechanics while hydraulic system simulation through SimHdraulics.Due to dual-acting asymmetric hydraulic cylinders,a dual-channel PID control strategy was used to control following response,displacement error,velocity respectively and dual-axis inclination.The hydraulic cylinder with push and return movements could be regarded as different hydraulic cylinders with different piston areas.The characteristic of dual-channel PID control meant when errors were adjusted with different PID parameter values.The simulation results showed that the maximum following error was 1.90 mm and the response time was 0.228 s under dual-channel PID control.The equilibrium time in the limit state was 2.98 s.Compared with single-channel PID control,the maximum control error was reduced by 49.3%,and the response speed was increased by 45.8%.Tests under eight different gradients were performed.These results showed that the response time of the auto leveling system was 0.328 s.With the increase of gradient,the maximum error of the test platform leveling was 1.14°,and the maximum root mean square error was 0.299°.The auto leveling system had a fast response,small following error,good follow-ability and high control accuracy under the dual-channel PID control and it can meet the requirements of ring slope operation.

关 键 词：农用底盘 坡地作业 主动平衡 试验平台 多物理域仿真 双通道PID控制 

分 类 号：U463.8[机械工程—车辆工程]