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The development of advanced ABS, EBS, and vehicle dynamics control systems requires significant resources and testing. Even in the most controlled environment, on-track vehicle tests are not repeatable. A heavy vehicle model combined with pneumatic brake hardware connected to actual brake system controllers creates a powerful engineering tool. This tool is useful for control system development, electro-mechanical actuator development, and brake system development. An existing heavy vehicle model is modified to interact with the realtime simulation hardware and the pneumatic brake system hardware. Data from several hardware in the loop simulations are presented.

The accuracy of existing rotational wheel dynamics models has been found to be insufficient for heavy vehicle Antilock Braking System (ABS) and Electropneumatic Braking System (EBS) simulation, specifically when wheelspeeds are at or near zero but the vehicle speed is not. Control strategies specific to ABS and EBS, the low frequency response of pneumatic actuation, and the practice of using fewer modulators than braked wheels require that a vehicle model be able to handle lockedwheel scenarios accurately. Commercially available models have been found unsatisfactory in this regard, and technical literature has not been found to address this issue.

An analysis of salt water effects and test methods to design Antilock Brake System (ABS) Electronic Control Units (ECUs) capable of withstanding the Heavy Vehicle frame mount environment. An examination of new and existing test methods and design techniques to ensure reliability over the life of the vehicle.

This paper presents an analytical solution of piston ring pack lubrication for two-cylinder truck air brake compressor. A system of nonlinear equations with seven variables was developed to describe lubrication phenomena of the piston ring pack for both fully flooded and starvation conditions. The full mass conservation boundary conditions defined by JFO ([14],[15]) theory were employed for complete description of the cavitation algorithm with enclosed and open cavitation patterns. Impact of the piston ring design parameters such as offset, crown height, and tension on the oil transport, lubrication conditions and friction losses of the compressor were discussed in details.