基于QFT算法的多功能履带导航平台多体耦合振动控制研究

QFT-based Multi-body Coupling Vibration Control for Multi-functional Crawler Navigation Platform

摘要:

针对丘陵山地柑橘果园非结构环境下，多功能履带导航平台自主作业时受路面振动激励影响，导致支重轮-车体系统振动，进而出现机械臂定位、导航误差等问题，本文开展了履带平台振动机理和控制研究。采用谐波叠加法搭建等级路面模型，建立履带-支重轮-地面多自由度振动理论模型，并研究振动传递机理，建立RecurDyn多体耦合动力学仿真模型，得到多功能履带导航平台的振动传递规律;采用最小二乘法辨识仿真结果，得到多组不确定性振动系统的线性传递函数，搭建不确定系统的定量反馈理论（QFT）控制器，通过与PID控制对比分析，验证了QFT控制系统鲁棒性和快速响应能力。采用极值法和加速度均方根评价试验结果，果园试验结果表明，QFT控制后，果园实测点位垂向加速度均方根减少为控制前的78.8%，满足振动作业国家标准要求，能够有效抑制振动，为多功能导航作业平台精准作业提供更好的适应性，显著提升了平台在非结构环境下导航定位精度与作业稳定性。

Abstract:

In the non-structured environment of citrus orchards in hilly and mountainous areas, when the multi-functional tracked navigation platform operates autonomously, it is affected by the vibration excitation of the road surface, causing vibration of the support wheel-car body system, and subsequently resulting in positioning and navigation errors of the mechanical arm. Therefore, the research on the vibration mechanism and control of the tracked platform was conducted. A hierarchical road model was established by using the harmonic superposition method, and a multi-degree-of-freedom vibration theoretical model of the tracked-axle-wheel-ground was established. The vibration transmission mechanism was studied, and a multi-body coupled dynamic simulation model of RecurDyn was established to obtain the vibration transmission law of the multi-functional tracked navigation platform. The simulation results were identified by using the least squares method, and multiple sets of linear transfer functions of uncertain vibration systems were obtained. A quantitative feedback theory (QFT) controller for the uncertain system was built, and compared with PID control, the robustness and fast response capability of the QFT control system were verified. The test results were evaluated by using the extreme value method and the root mean square value of acceleration. The orchard test results showed that after QFT control, the root mean square value of the vertical acceleration at the measured points in the orchard reduced to 78.8% of the data before control, meeting the requirements of the vibration operation national standard, effectively suppressing vibration, providing better adaptability for precise navigation and operation of the multi-functional navigation platform, and significantly improving the navigation positioning accuracy and operation stability of the platform in non-structured environments.