Form 101 – Proposal Improving Safety, Comfort and Efficiency of Convoy Vehicles through Novel Preview Control

1 Improving Safety, Comfort and Efficiency of Convoy Vehicles Through Novel Preview Control Fuel consumption and emissions are major concerns associated with heavy trucks, and both can be reduced if the trucks travel in a very closely-spaced platoon [1]. The military deploys trucks in closelyspaced convoys where the terrain can be highly variable and the drivers often inexperienced. Traffic accidents are a major cause of death for soldiers during peacetime [2]. Automated highways in which groups of vehicles travel very closely have been envisioned to improve traffic flow and safety [3]. The applicant’s research team will pursue improvements in ride quality and active safety that take advantage of the close spacing and similar paths of convoy vehicles. The proposed active systems will increase occupant comfort, reduce fatigue, improve vehicles’ ability to execute evasive maneuvers, and contribute to energy reduction. Both ride quality and roadholding of actively-suspended vehicles (i.e., with a force actuator or active damper in the suspension system) can be improved by sensing the road ahead of the vehicle and using this information in a preview controller [4-8]. For convoys, the overall response of the preceding vehicle(s) is proposed as a means to generate preview controller information for follower vehicles. The vehicles ahead of a given vehicle become the preview sensors, instead of look-ahead sensors mounted on the front bumper of the vehicle. The proposed research will design and simulate such preview controllers, and address issues related to stability and robustness. Physical implementation will be done using reduced-scale vehicle hardware. The use of lead-vehicle-as-sensor will then be applied to yaw and roll dynamics to improve handling and ride quality during cornering, when encountering bumps, and when road friction suddenly changes as in winter driving scenarios. Active suspensions reduce the longitudinal energy lost to vertical suspension motion [9-10], thereby reducing vehicle energy consumption. The potential reduction for heavy commercial or military vehicles with preview-active suspension and intelligent cruise control will be simulated. Recent Research Progress The research builds upon recent results by the applicant and his HQP, as part of his current NSERC Discovery Grant (DG) and Auto21 projects. Preliminary research on preview-active suspension using leading vehicle states instead of look-ahead sensors [8] has shown improvements in performance, with lower power demand by the actuators, for a simulated two-vehicle convoy represented by quarter-car models. Tire deflection was estimated with a Kalman filter, and used to generate a road profile, which was then fed into an optimal preview controller for the follower. No look-ahead sensors would be required using such an approach. Road estimation methods similar to [8,28] gave limited success, and further estimator design using practical measurements is proposed in the Methodology section.