通过分析车辆悬架弹簧静挠度和动挠度的功能特性,得到了悬架弹簧的理想刚度特性.这一理想工作特性可以通过在普通弹性元件的平衡点并联具有负刚度特性的元件实现,由此提出了车辆悬架的负刚度控制策略.通过数值仿真,对比分析了悬架负刚度半主动控制策略、天棚阻尼半主动控制策略、理想天棚阻尼控制策略的控制效果.对磁流变液减振器负刚度特性的分析表明,其可以作为具有负刚度特性的半主动作动器使用.讨论了在基于磁流变液减振器的半主动悬架中负刚度控制策略的技术实现方法,通过仿真和实验对负刚度控制策略和天棚阻尼控制策略进行了对比分析,结果表明,负刚度半主动控制能更好的抑制振动对车身加速度和轮胎动位移的影响.
On the basis of function principle analysis of vehicle suspension spring, the ideal characteristic of suspension spring was presented. This ideal characteristic can be obtained by parallel a spring which has negative stiffness characteristic with a normal spring. To approach the ideal characteristic of suspension spring, a negative stiffness based control strategy was presented. Control results of negative stiffness semi-active control strategy, skyhook semi-active control strategy and ideal skyhook control strategy were compared by simulation. For its negative stiffness characteristic, the magneto-rheological damper can be used as an actuator with negative stiffness characteristic. The implementation approach of negative stiffness based control strategy using magneto-rheological damper was discussed. The negative stiffness control strategy and the sky-hook control strategy were compared by simulation and rig test. Analytical result shows that the negative stiffness based control strategy can restrain the influence of vehicle body and dynamic tyre reflection caused by vibration.