最优化技术的高速叉车车身转动惯量辨识方法

Identification Method of Moments of Inertia of Body about High Speed Forklift Based on Optimization Technology

针对某型高速叉车底盘与车身匹配分析的虚拟样机,为确保其仿真分析的置信度,依托整车平顺性测试结果,采用最优化技术辨识车身转动惯量并用于虚拟样机的修正。具体地,一方面,由整车平顺性测试结果中获得其前、后悬架系统悬挂质量部分的固有频率,即偏频。另一方面,将车身转动惯量视为参数化变量,建立参数化的车身振动分析之理论模型。进而,基于理论模型计算而再次得到前、后悬架系统偏频,并优化车身转动惯量的参数化取值,最终使悬架偏频的理论计算结果与相应的测试结果趋于吻合,此时的车身转动惯量取值即为最终的辨识结果,由此大大提高了这一建模所需关键性基础数据的精确性。而相关的整车动态测试结果则验证了所提方法的有效性。

Relying on the test results about vehicle＇s ride comfort, the moments of inertia of the body were identified by means of the optimization technology and used to amend the Function Virtual Prototype of dynamic simulation about matching analysis between the chassis and body of a high speed forklift in order to insure the reliability of the simulation. Concretely, on the one hand the natural frequencies of the suspending mass of the front and rear suspension systems, i.e., the offset frequencies were obtained from the test results about vehicle＇s ride comfort; on the other hand the moments of inertia of the body were regarded as parameter variables so that the parameter theory model of the body vibration analysis was set up. Then the offset frequencies of the front and rear suspension systems were calculated and obtained again based on the theory model, and the parameter values of the moments of inertia of the body were optimized to make the calculating offset frequencies being according with the test ones. In fact it is the optimal values of the moments of inertia of the body obtained here that were the final identified results. So the accuracy of those of the pivotal data base was improved consumedly, and the effect of the method put forward here was validated with the interrelated vehicle dynamic test results.