车辆横摆转动惯量及轮胎侧偏刚度识别方法的研究

车辆参数辨识在汽车正逆向开发及控制器设计等方面是必要前提与技术难点.目前参数的获取主要有两种方法:通过仪器测量的方法和系统辨识技术.研究了一种能够识别横摆转动惯量及轮胎侧偏刚度的实验辨识方法.该方法通过汽车转向盘转角脉冲输入获得的实验数据,首先采用时域法辨识车辆横摆角速度对转向盘转角和侧向加速度对转向盘转角的传递函数,再通过非线性最小二乘法拟合传递函数中包含的横摆转动惯量和前后轮胎侧偏刚度,使所得频响特性和辨识所得频响特性误差最小,最后通过仿真验证该方法的理论可行性.所提的实验辨识获得横摆角速度和轮胎侧偏刚度参数的优点是无需特制或购买专用测量设备,尤其在实验条件受限情况下,更具有重要的工程实际意义.

Research on System Identification of Vehicle Moment of Inertia about the Z axis and Tire Cornering Stiffness

Vehicle parameters identification play key role in vehicle design and controller design. Currently, there are 2 means to get vehicle parameters, through physical instrumental or system identification techniques. This paper focuses on identification approach for vehicle moment of inertia about the Z axis and tire cornering stiffness. The experimental data is from vehicle steering wheel angle pulse input, time-domain method is used to identify the transfer function of yaw rate and lateral acceleration to steering wheel angle firstly, and then nonlinear least-squares fitting method is used to fit vehicle moment of inertia about the Z axis and tire cornering stiffness to make the minimal error. Finally, theoretical feasibility of the method is verified by a simulation case. There are significant and practical advantages, such as no need for special instrumental, by virtue of system identification to obtain the vehicle parameters.