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Wear of brake disc is normally faced with sophisticated experimental methods, a basic overview on the phenomena related to disc wear is presented in this paper. DTV consists in a heterogeneous wear of the disc surface and it is caused by two factors: run-out and the mechanism of disc wear. The importance of DTV is due to the vehicle vibrations that high DTV values can cause during braking. A model, that considers iron oxide layer evolution on disc surface, can evidence some of the principal characteristics of disc wear. In this model the wear rates of disc gray cast iron and iron oxide layer are considered as some of the principal factors in DTV evolution, as well as the kinetics of the chemical reactions involved.

Newer automobiles have complex dynamic and stability controls due to regulations, competition, and safety concerns. More systems require testing at the subcomponent level to ensure proper operation in the final vehicle assembly. Many of the stability and navigation features originally designed for aircraft components are now being incorporated into automobiles. Certain types of motion test simulators were originally designed for testing aircraft sensors as: gyroscopes, inertial navigation systems (INS), inertial measurement units (IMU), and attitude heading and reference systems (AHARS) This same type of equipment is now used for automotive testing as: airbag fuse sensors, anti-skid sensors, rollover sensors, vehicle stabilization systems, active suspension sensors, and navigation systems.

In order to reduce injury caused by collision accidents and minimize disruption to drivers, slight steering is added on top of emergency braking. ...To make the scenarios more representative, Euro NCAP testing standard is referenced and an analysis on real collision accidents data is taken into account. Simulation results support that strategy based on ICS is effective in scenarios involving VRU and that slightly steering is effective in reducing injury and disruption to the driver.

The analysis presented here updates and expands previous research in which rollover critical events were classified based on a detailed review of about 500 police-reported single-vehicle rollover crashes of ESC-equipped vehicles. In order to compare the rollover performance of vehicles with and without ESC for the present study, an additional sample of 150 police reports on non-ESC passenger cars and 196 police reports on light vehicles with ESC in single-vehicle rollovers were obtained, and detailed coding of rollover scenarios was performed. The coding effort was undertaken by an engineering team and focused on critical events leading to rollovers (departure from road, loss of directional control, impact with an object, and departure from road with possible driver's input); driver factors (alcohol/drug involvement, speeding, inattention, distraction, fatigue, and overcorrection); and environmental factors.

Despite the general similarity of U.S. and European heavy trucks, there are differences in design properties that affect braking and turning performance. A European tractor-semitrailer was studied for the purpose of comparing its properties to those of U.S. vehicles and assessing the comparative performance. Mass, suspension, and braking system properties of the European tractor and semitrailer were measured in the laboratory and on the proving ground. Turning and braking performance qualities were evaluated by computer simulation and by experimental tests. In turning performance the European combination had a 9 percent advantage in rollover threshold, compared to a generic U.S. vehicle with properties that were in the midrange of U.S. design practice. Higher suspension roll stiffness and higher chassis weight on the European tractor and semitrailer accounted for the higher threshold.

Because of an increasing popularity of the SUV and Light Truck with an elevated center of gravity, the rollover propensity is higher than before. This paper proposes a method to detect and prevent an impending rollover of the vehicle using Electronic Stability Control(ESC). The Rollover Prevention(ROP) function determines a rollover critical situations based on the rollover propensity index and generates a proper activation through a brake and engine intervention. The rollover propensity index is calculated from the relative distance of the trajectory to the threshold on the phase plane of roll-angle and roll-rate. The threshold on the phase plane is deduced from the conservation of energy in the roll model. For the detection and activation of continuous rollover phenomena, we use the TTL concept that presents a gradually increasing rollover propensity. The proposed algorithm in this paper is shown to be effective in mitigating a rollover through the simulation and vehicle test.

This discussion paper reviews trends and priorities in road and vehicle safety. Seatbelts, drunken driving awareness, rear stoplights, industry-government cooperation, anti-lock or anti-skid braking, steering systems, lighting and electronics have improved safety. Vehicle design and construction, International Uniform Safety Standards for harmonization of standards, information exchange, and component design are areas for development.

Industry response to safety objectives and also to government regulation has produced a large number of safety enhancing engineering developments, including radial tires, disc brakes, anti-lock brakes, improved vehicle lighting systems, better highway sign support poles, padded instrument panels, better windshield retention systems, collapsible hood structures, accident sensitive fuel pump shut-off valves, and other items. A significant development was the design of the energy absorbing front structures.

Results of this study can be used in enhancing the braking system of a vehicle, investigating traffic accidents, and also designing or improving racecars.

The results from the case study highlight frontal impact situations from real world accident data that have the greatest potential in terms of improving accident outcome. One of the first stages in the development of forward dectection driver support systems is a system to detect vehicles travelling in the same direction. ...It involves a systematic and new way of examining accident data in order to extract information concerning pre-crash situations. One problem area when implementing collision mitigation systems is being able to achieve sufficient target discrimination. ...Here, braking tends to be efficient in terms of accident mitigation; hence reducing AIS1 spinal injuries in this specific traffic incidence. The need for an increased level of object discrimination becomes obvious though, when taking all frontal impacts into account.

A long standing problem with heavy vehicle stability has been rollover. With the higher center of gravity, heavier loads, and narrower tracks (as compared to passenger vehicles), they have a lower rollover stability threshold. In this paper, a rollover stability control algorithm based on a two-degrees-of-freedom (DOF) and a three-DOF vehicle model for a two-axle truck was developed. First, the 3DOF model was used to predict the future Lateral load Transfer Rate (LTR). Using this LTR value, the dynamic rollover propensity was estimated. Then, a robust output feedback gain control rollover stability control algorithm based on the combination of active yaw control and active front steering control was developed. A H₂/H∞/poles placement multi-objective control strategy was developed based on the 2DOF reference model.

Results from testing the feedback system show that it effectively detects potential collisions and provides warning signals, reducing the risk of accidents. The ABS is designed to prevent dangerous braking scenarios in single-track vehicles, such as rear-wheel lift-off and front-wheel locking. ...The system provides real-time warnings to the rider, thereby reducing the risk of accidents. The implementation of the ABS improves riding stability and steerability, providing a safer and more pleasant riding experience.

The authors believe this testing protocol will be useful to Fleet Managers and Maintenance Personnel, Law Enforcement specializing in Commercial Vehicle Inspection and Accident Investigators who need information on brake system performance.

In racing design, important and urgent problems have to be solved: on one hand an high level of optimization of shapes and weights is needed for achieving high performance, on the other hand a quick development time is necessary to reduce the time between the new concept and the actual application on racing car as many redesigns are carried out during racing season. In the present paper, a quick design strategy for the brake disc mounting bell is proposed in order to reduce the development time and to reach an high accuracy for improving car performance. The brake disc mounting bell is a poorly studied component, but it has important side effects on the handling and the efficiency of a racing car. The proposed design strategy is developed by means of thermal and static finite element analysis (FEA).

The circumstances of the accident are reviewed, and how the accident was modeled using ADAMS. ARB is then added to the vehicle model to examine what would happen if ARB had been on the vehicle. ...One case uses the same steering as in the accident, and one case uses the same path as the accident. In both of these cases, ARB would have prevented the vehicle from rolling over. ...A single vehicle on-road rollover accident of a small van is used to examine the effectiveness of the Anti-Rollover Braking System (ARB).

In the prototype development, the reliability and the ability of protection design of the battery in the whole vehicle against the environmental loads are mainly studied, especially, heat and cold, water, shock, and the accident impact. In addition, it is carried out the performance improvement by the heat management design of the motor to meet the practical use condition.

The course has been approved by the Accreditation Commission for Traffic Accident Reconstruction (ACTAR) for 7 Continuing Education Units (CEUs). Upon completion of this course, accredited reconstructionists should mail a copy of their course certificate of achievement and the $5 participant CEU fee to ACTAR, PO Box 1493, North Platte, NE 69103.

It does not include damage that occurred during heavy maintenance or overhaul activity, taxi incidents or accidents where an aircraft under tow collided with a piece of GSE.

The durability performance of brake hoses is a crucial issue for such components. Accelerated fatigue testing of brake hoses is necessary for understanding achievable lifetime, actually computation of durability is quite cumbersome due to the many different materials the hoses are made from. Despite SAE standards are available, accelerated testing of brake hoses subject to actual torsional and bending stresses seem important to provide relevant feedback to designers. In this paper, an innovative methodology for assessing the fatigue behavior of brake hoses of road vehicles is proposed. A dynamic testbed is specifically designed and realized, able to reproduce the actual assembly conditions of the hoses fitted into a vehicle suspension. The designed testbed allows to replicate actual loading conditions on the brake hoses by simulating the vertical dynamics and steering of the suspension system together with brake pressure.

Determination of vehicle speed at the time of impact is frequently an important factor in accident reconstruction. In many cases some evidence may indicate that the brake pedal of a striking vehicle was disengaged, and the vehicle was permitted to idle forward prior to impacting the target vehicle.