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A vehicle model is an important factor in the development of vehicle control systems. Various vehicle models having different complexities, assumptions, and limitations have been developed and applied to many different vehicle control systems. A 14 DOF vehicle model that includes a roll center as well as non-linear effects due to vehicle roll and pitch angles and unsprung mass inertias, is developed. From this model, the limitations and validity of lower order models which employ different assumptions for simplification of dynamic equations are investigated by analyzing their effect on vehicle roll response through simulation. The possible limitation of the 14 DOF model compared to an actual vehicle is also discussed.

This paper presents a real-time computer system for the control of refrigerant flow in an automotive air conditioning system. This is an experimental system used to investigate the potential advantages of electronic flow control over conventional flow control (using an orifice tube or thermal expansion valve). Two features of this system are presented. First, the system organization is described. Second, the control and interface software are presented. The emphasis is on the software. The system is organized as a closed loop control system. The inputs to the controller are measurements of the refrigerant system. In particular, thermocouples are used to measure the refrigerant temperature before and after the evaporator. The analog thermocouple signals are converted to digital form by an off-the-shelf, portable, data acquisition system (DAQ). Via a parallel port link, these digital measurements are transfered to a laptop computer.

Vehicle roll dynamics is strongly influenced by suspension properties such as roll center height, roll steer and roll camber. In this paper, the effects of suspension properties on vehicle roll response has been investigated using a multi-body vehicle dynamics program. A full vehicle model equipped with front MacPherson and rear multilink suspensions has been used for the study. Roll dynamics of the vehicle were evaluated by performing fixed timing fishhook maneuver in the simulation. Variations of vehicle roll response due to changes in the suspension properties were assessed by quantitatively analyzing the vehicle response through simulation. Critical suspension design parameters for vehicle roll dynamics were identified and adjusted to improve roll stability of the vehicle model with passive suspension. Design of Experiments has been used for identifying critical hardpoints affecting the suspension parameters and optimization techniques were employed for parameter optimization.

The new wireless rotor electrical machine has all the coils placed on the stator. The laminated wireless rotor serves as a magnetic field switcher. A wireless rotor is cold, and it facilitates machine cooling. The model of the wireless rotor machine includes electrical and mechanical components. The wireless rotor machines can find an application in practice because they have advantages over existing devices. In modeling, we use a new approach. We consider a motor as a natural control system with torque feedback. Such an approach simplifies analyses and adjustment of the operation of an electrical machine. First, we analyze an open-loop control system without torque feedback. In this case, by changing the rotor speed under external torque, we can receive the torque-speed motor characteristics. After some adjustments to the open-loop system, we can consider the close loop control system with torque feedback. We use a space vector representation for sinusoidal electric components.

The urban trams with a low floor are more convenient for the passengers, and with a high floor - more cheaply and more technologically during manufacturing and operation. The combined advantages those and others in themselves are trams with average height of a floor, but for this purpose it is necessary to lower height of tram carriages, that is reached by application of electric motors with a small stator external diameter. It is offered in this the perspective electric drive on the base of the synchronous motor with independent excitation. The salient rotor poles of the motor do not contain windings. The motors stator is carried out on the base of the stator body of regular AC electric motor. The multiphase winding is located in the stator. A winding section, which conductors settle down above the between rotor poles, carry out a role of the excitation winding, and others, which conductors lay above poles, - a role of the armature winding.