Investigation into on-road vehicle parameter identification based on subspace methods
Investigation into on-road vehicle parameter identification based on subspace methods
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DOI：
10.1016/j.jsv.2014.07.012
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发表时间：
2014-12-02
影响因子：
4.7
通讯作者：
Zhang, Nong
中科院分区：
文献类型：
--
作者：
Dong, Guangming;Chen, Jin;Zhang, Nong
路面轮胎激励的随机性可以激发道路车辆的弹跳、俯仰和侧倾模式的低频乘坐振动。本文基于子空间辨识方法，仅通过测量车辆簧上质量和簧下质量的加速度，就可以在一定精度下估计出车辆的模态参数和质量转动惯量。车辆弹跳、俯仰和侧倾模式的特征在于它们的大阻尼（阻尼比0.2-0.3）。针对高阻尼模态，比较了两种子空间辨识方法，一种是利用输入/输出数据，另一种是仅利用输出数据。结果表明，在给定相同数据长度的情况下，仅使用输出数据的方法可以明显地观察到较大的模态识别结果误差，而额外使用输入数据将显著减小估计方差。代替使用轮胎力作为输入，这是难以测量或估计，簧下质量的垂直加速度作为输入。理论分析和Monte Carlo实验表明，在车速不太高的情况下，以簧下质量加速度为输入的子空间辨识方法比以路面轮胎力为输入的方法能得到更准确的结果。在模态参数识别之后，如果车辆质量及其重心是预先确定的，则可以仅使用识别的频率直接计算道路车辆的侧倾和俯仰惯性矩，而不需要精确估计模态形状向量和多变量优化算法。(C)2014爱思唯尔有限公司版权所有。
The randomness of road-tyre excitations can excite the low frequency ride vibrations of bounce, pitch and roll modes of an on-road vehicle. In this paper, modal parameters and mass moments of inertia of an on-road vehicle are estimated with an acceptable accuracy only by measuring accelerations of vehicle sprung mass and unsprung masses, which is based on subspace identification methods. The vehicle bounce, pitch and roll modes are characterized by their large damping (damping ratio 0.2-0.3). Two kinds of subspace identification methods, one that uses input/output data and the other that uses output data only, are compared for the highly damped modes. It is shown that, when the same data length is given, larger error of modal identification results can be clearly observed for the method using output data only; while additional use of input data will significantly reduce estimation variance. Instead of using tyre forces as inputs, which are difficult to be measured or estimated, vertical accelerations of unsprung masses are used as inputs. Theoretical analysis and Monte Carlo experiments show that, when the vehicle speed is not very high, subspace identification method using accelerations of unsprung masses as inputs can give more accurate results compared with the method using road-tyre forces as inputs. After the modal parameters are identified, and if vehicle mass and its center of gravity are pre-determined, roll and pitch moments of inertia of an on-road vehicle can be directly computed using the identified frequencies only, without requiring accurate estimation of mode shape vectors and multi-variable optimization algorithms. (C) 2014 Elsevier Ltd. All rights reserved.