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This paper discusses the development of engine and vehicle model for performing dynamic emulation experiments on vehicle transmissions. In order to reduce costs and shorten new vehicle development cycle time, vehicle simulation on the driveline test bench is an attractive alternative at the development phase to reduce the quantity of proto vehicles. This test method moves the test site from the road to the bench without the need for real chassis parts. Dynamic emulation of mechanical loads is a Hardware-in-the-loop (HIL) procedure, which can be used as a supplement of the conventional simulations in testing of the operation of algorithms without the need for the prototypes. The combustion engine is replaced by an electric drive dynamometer, which replicates the torque and speed signature of an actual engine. The road load resistance of the vehicle on a real test road is accurately simulated on Load dynamometer.

In order to improve the performance of automatic emergency steering and collision avoidance of intelligent vehicle, two automatic steering control methods under ideal model following control are proposed. The two ideal reference models are the reference model with zero sideslip angle of vehicle gravity center and the reference model with no phase-lag in vehicle lateral acceleration. The control system adopts the combination of outer loop and inner loop. In the design of the outer loop controller, the optimal control is used to get the steering wheel angle needed to avoid collision. The inner loop controller uses feedforward and feedback control to get the required front and rear wheel steering angles. Taking vehicle two degrees of freedom (DOF) lateral dynamics model as the research object, the vehicle collision avoidance reference trajectory is obtained through the fifth-degree polynomial.

The transient response characteristics of a vehicle under steering angle input are important evaluating indicators of vehicle handling stability. For a new developed vehicle, which was found that the transient response under steering angle input is too slow at high speed, a rigid-flexible coupling vehicle model is established in ADAMS/Car based on multi-body dynamics theory. Improvement measures are studied and put forward to improve the transient response characteristics of the vehicle. The sensitivities of transient response to various parameters are analyzed. The optimization method of adjusting the tire cornering stiffness and moving forward the mass center is adopted. The test data after improvement show that the response time of yaw velocity is shortened obviously. Meanwhile, the value of evaluation index in other tests remains basically unchanged.