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This paper describes the measurement procedures and results of vehicle tires using a synchronized optical and analog system. The device detects 3D positions, forces, moments, and contact pressures of a tire on the testing machine. The infrared light is captured by a vision sensor and the load cells as well as pressure transducers were recorded by an A/D board. Results from direct measurements, tire force machine (TFM) measurements, and dynamo measurements are presented. Vertical, lateral and fore-aft forces were applied in the TFM, where side slip and lock-up braking force vs. the normal load and yaw angles, and their relation with 3D tire deformations were measured. For the dynamometer testing, free rolling tests were conducted.

The application of velocity-feedback active systems to control the vehicle ride quality is studied in this paper. The control force of the active damper is derived from velocity signals, which does not need position feedback. The controller of the optimal active damper is developed from second-order equations. The control system could be used when the full-state information is not available. The power spectrum of both full-state suspension and active damping systems can be computed through a converted road roughness.

This paper presents the development of Wright State's electric racecar. The car utilizes two AC induction motors and controllers and is propelled by a timing belt/pulley assembly on the rear axle. Conventional lead-acid batteries are adopted due to low installation cost. Differential equations that describe traction and propulsion capabilities as well as power consumption were formulated. Instead of using section-to-section estimation, “closed-form” solutions for the traction, propulsion and power requirement were derived. The simulation results for vehicle traction and propulsion are presented. The car was tested on tracks and successfully raced in various events.

This paper presents the application of a multibody formulation program to generating equations of motion for commercial vehicles. The formulation procedure adopts the separated-form virtual work principle. Equations are expanded using generalized coordinate partitioning through a Jacobian matrix expansion. The inertia force vector is separated into nonlinear, linear and time-dependent terms, and the generalized force vector is derived from virtual energies. Friction forces are included in the formulation. Nonlinear and linearized models are provided in a symbolic FORTRAN form allowing the control design be implemented with second-order or first-order equations. A fourth-fifth order Runge-Kutta-Fehlberg's algorithm with self-adjustable step sizes is utilized to numerically integrate the reduced systems. An example, a six-axle tractor-semitrailer model is demonstrated.