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Recently, the development of various driver assistance systems into today's vehicle have increased due to the availability of affordable advanced electronics. With this increase in electronic content on today's commercial vehicles, various opportunities for sensor fusion are opened up, primarily because the sensors are typically part of the ECU cluster, and always measuring either driver input, vehicle states and potentially the environment around the vehicle. Given the larger variance in vehicle mass and length for commercial vehicles, as opposed to passenger cars, sensor data integrity and robustness is important to assure that all the sensors are reporting the same information, so that safety-critical Driver Assistance Systems can intervene effectively and robustly.

Forward collision mitigation systems (FCMS) are becoming standard in passenger car vehicles with the current trend of safety technologies development. Currently, safety systems are on the road towards widespread acceptance in the commercial vehicle industry. Whereas the full Electronic Stability Control (ESC) system attempts to sense the states of the vehicle to assist the driver to maintain directional control of the vehicle, current FCMS attempts to sense the environment around the front of the vehicle and either warns the driver to react or intervenes by slowing down the vehicle autonomously. Some of the latest developments in FCMS for commercial vehicles will be discussed, together with an outlook of future systems. This study will also examine some of the common scenarios that forward collision mitigation systems can be beneficial in, especially for commercial vehicles. The scenarios will be investigated using Hardware-in-loop-simulation, and the results discussed.

The application of stability systems on heavy vehicles clearly has numerous advantages, when the cost of the cargo, the service life of vehicles, and the vehicle potential for damage are taken into account. The primary objective of such systems is to assist the driver to maintain control in the face of uncertain driving conditions. The dynamic effects of such system, however, are not widely tested by the industry. The study presented in this paper will present an evaluation of the effects of full and partial stability systems on tractor-trailers using hardware-in-the-loop simulation. With the advancement of simulation capabilities that enables the repeatability of maneuvers, the study presented attempts to provide various deterministic “what-if” scenarios under various vehicle stability system combinations.

Electronic Stability Control (ESC) has presented itself to be a rather significant technological advancement in passenger car safety within the last few years. For the commercial vehicle industry, stability systems have been an option available for tractor-semitrailer within the last few years. However, there are axle weight limits imposed on commercial vehicles, unlike emergency vehicles which are allowed to be loaded to the maximum axle weight ratio. With the fact that fire trucks are carrying high CG loads and may typically be travelling at speeds higher than the normal driving speed for a road, one of the recommendations is that stability systems become available as standard in heavy duty emergency vehicles such as firetrucks. This study will analyze several scenarios commonly encountered by emergency vehicles such as firetrucks and demonstrate the benefits of stability systems for heavy duty emergency vehicles.

The new RSDII (Reduced Stopping Distance, phase 2) regulation creates an increased emphasis by the heavy truck industry to ensure that brake systems are properly chosen and optimized. This regulation has led to vehicles being fitted with much more powerful brakes. However, despite the intent of these new brakes to provide larger braking forces for shorter stopping distances, the performance of vehicles is still limited by the maximum friction coefficient between the vehicle's tires and the road. In order to get the most out of these new brakes, it is essential that the entirety of the vehicle be taken into account. With the use of a hardware-in-the-loop simulation tool, this paper will present stopping data predictions from a variety of vehicles of varying brake torque and wheelbase. It will be shown how these factors change the way a vehicle behaves under panicked stopping situations.

Global demand for diesel fuel has predominantly driven the Commercial Vehicle industry to seek out fuel consumption reduction technologies to integrate into their products in order to provide value to their customers. Since air generation and use directly affect fuel consumption, active management of these systems provides a new avenue to achieving future fuel and green house gas (GHG) emissions requirements. Using a turbocharged compressor coupled with a clutch mechanism delivers air at maximum efficiency while simultaneously removing parasitic losses during an inactive state. The electronic air dryer monitors vehicle status and actively manages the charging and regeneration activities to minimize waste. Lastly, the use of an engine air boosting device enables both steady state and transient savings by means of driveline modifications such as adaptive shifting and rear axle ratio changes without the associated dynamic performance degradation.