Using lead vehicle response to generate preview functions for active suspension of convoy vehicles

Improving ride quality and active safety systems of convoy vehicles (vehicles traveling with close following distances on a specified path) can reduce fatigue and injury in military vehicle deployments and intelligent vehicle highway systems. A form of preview-active suspension control to improve convoy vehicle ride quality is proposed, wherein dynamic response of the lead vehicle is used to generate feed forward preview control gains in addition to feedback control gains for the follower vehicle suspensions. In contrast to conventional preview control with look-ahead sensors that can be expensive and unreliable, the tire deflection of the lead vehicle is estimated with a Kalman filter and used to generate road profile information for the preview controller of the followers. A virtual convoy, composed of a lead vehicle with active suspension system, and a follower vehicle with preview-controlled active suspension, is developed in MATLAB and SIMULINK. The results show improved ride comfort and road holding of the follower vehicle with the novel preview approach compared to the lead vehicle with conventional active suspension. Moreover, the power demand for the follower vehicle suspension is much less than for the lead vehicle. The road holding metric (tire deflection) was more sensitive to measurement noise than was ride quality (sprung mass acceleration); however, meaningful improvements were achieved for reasonable sensor noise levels.