含MRD的拖拉机驾驶室悬置系统半主动控制研究

Research on Semi-Active Control of Cab Suspension System with MRD for Tractor

提出一种含磁流变减振器(MRD)的拖拉机驾驶室悬置系统,针对MRD的阻尼非线性力学特性,基于双曲正切函数建立了MRD阻尼力Tanh函数模型。根据MRD阻尼力输出特性试验数据,采用遗传算法有效辨识了模型中的相关参数。为实现MRD阻尼力的有效控制,结合简化的Tanh函数模型,提出一种MRD阻尼力反馈线性化控制方法。建立了拖拉机车架-驾驶室-座椅系统状态空间数学模型,基于振动传递特性,确定了驾驶室悬置系统隔振性能评价指标。以振动响应量最小为控制目标,利用最优控制理论进行了MRD阻尼力控制器设计,实现MRD阻尼力的最优调节。仿真计算结果表明,所设计的控制器能够有效提高含MRD的拖拉机驾驶室悬置系统隔振性能。

A cab suspension system with magnetorheological damper（MRD）for tractor is proposed. For the nonlinear damping characteristics of MRD,a damping model is established based on Tanh function. On the basis of the experimental data of MRD mechanical properties,the key parameters of the model are identified accurately by genetic algorithm. To achieve the effective control of damping force of MRD,a feedback linearization control method is proposed based on the simplified Tanh function model of damping force. Then,the state-space mathematical model of frame-cab-seat system for tractor is established. Based on the vibration transmissibility,the vibration isolation performance evaluation indices for cab suspension system are determined. To minimum the vibration response at the seat,the damping force control law is derived based on optimal control approach,thus the optimal regulation of the MRD damping force can be achieved. The effectiveness of the proposed controller for improving the vibration isolation performance of cab suspension system is verified by simulation results finally.