负载高位抖动/晃动工况下叉车动态纵向稳定性分析

Analysis of dynamic longitudinal stability of forklift under jitter/slosh condition at high load

考虑门架变形、轮胎刚度阻尼以及车体惯性质量等参数的影响,搭建了基于VL motion的纵向动力学模型,结合门架液压系统模型建立基于AMESim与VL motion的联合仿真分析平台,辨识负载高位抖动/晃动工况中惯性力矩的时变特征,根据零力矩点理论(Zero Moment Point,ZMP)分析了叉车纵向堆垛的稳定条件。针对叉车纵向堆垛过程中由于液压系统冲击引起的失稳问题,设计了一种组合式液压缓冲装置。仿真结果表明,由于组合式液压缓冲装置的节流与吸能作用,减轻了负载运动状态变化所引起的液压系统冲击问题,提高了叉车纵向堆垛稳定性。

Considering the influence of parameters such as gantry deformation,tire stiffness damping and vehicle body inertia mass,a longitudinal dynamics model based on VL motion was built.Combined with the gantry hydraulic system model,a joint simulation analysis platform based on AMESim and VL motion was established.Based on the above analysis platform,the time-varying characteristics of inertia torque in jitter/slosh conditions at high load were identified,and the stability conditions of vertical stacking of forklift trucks were analyzed according to the Zero Moment Point(ZMP)theory.Aiming at the instability caused by the impact of hydraulic system during the vertical stacking of forklift truck,a combined hydraulic buffer device was designed.The simulation results showed that the throttle and energy absorption of the combined hydraulic buffer device could reduce the impact of hydraulic system caused by the change of load motion state and improve the stability of vertical stacking of forklift truck.