Showing papers on "Rear-end collision published in 2002"

Alert algorithm development program: nhtsa rear-end collision alert algorithm

Abstract: As part of its ongoing research activities supporting the development, testing and evaluation of collision warning systems, the National Highway Traffic Safety Administration (NHTSA) developed an experimentally-based rear-end collision warning algorithm and sponsored analysis of the algorithm using test data collected during an intelligent cruise control field operational test. In October of 1999, NHTSA sponsored a joint research effort with the Johns Hopkins University Applied Physics Laboratory to refine the algorithm previously developed by NHTSA and translate it into structured C code capable of running in the real-time processor environment of a prototype vehicle-based system. This report describes the theory of operation of the NHTSA algorithm and its theoretical performance under a defined set of typical rear-end collision scenarios. Test data from a series of controlled test track studies are discussed and an estimate of the number of rear-end collisions that could be avoided using the NHTSA algorithm is also presented in the report.

Driver distraction, warning algorithm parameters, and driver response to imminent rear-end collisions in a high-fidelity driving simulator

Abstract: This report presents three experiments that use a high fidelity driving simulator to examine driver response to imminent rear-end collision situations. The first experiment examines how variations in algorithm parameters affect the ability of a Rear end Collision Avoidance System (RECAS) to aid distracted drivers in avoiding an imminent collision. The results show that an early warning helps drivers to react more quickly and to avoid more collisions than either a late warning or no warning. The second experiment examines the ability of the RECAS to help non-distracted driver avoid an imminent collision. The results show that the RECAS benefits drivers even when they are not distracted. The third study examines the effect of manipulating the urgency of the auditory warning by changing the volume of the warning tone. Varying the volume levels for the warning tones had no systematic effect on the driver response. These studies show that the RECAS provides a potential safety benefit by reducing the time it takes drivers to remove their foot from the accelerator. The warnings do not speed the drivers' application of the brake, increase their maximum deceleration, or affect their mean deceleration.

Differential occupant kinematics and forces between frontal and rear automobile impacts at low speed: evidence for a differential injury risk.

Abstract: Numerous factors are believed to influence the risk for injury to the cervical spine in low speed automobile crashes. These include occupant stature, gender, position, age, pre-existing health status, and awareness of impending crash. Factors extrinsic to the occupant that are thought to influence the risk for injury include seat back characteristics, head restraint geometry, type of restraint system used, crash speed, relative vehicle mass, and the direction of impact. Several studies have indicated that rear impact crashes are associated with greater risk for injury and, in some cases, a worse prognosis. Epidemiological studies have identified many risk factors, but the retrospective study design and wide ranging variables of real life crash scenarios has not allowed careful comparison of specific variables. We sought to answer the question concerning the possible reasons for the disparity in risk between front vector crashes and rear vector crashes using human subject crash testing.

Safety distance about car-following

Abstract: It is pointed out that the traffic accident mostly result in improper driver's action.The driver's capability of response time and speed estimation are studied,and driving performance by car following in traffic is investigated,in order to calculate the appropriate driving safety distance,which assures that neither the rear end collision occurs nor road capacity is affected.If the following distance is S(m),and the following vehicle's velocity is V(m/s),the study results show that when SV/2,the following is safety under the good condition of driver and vehicle,when S2V,the following is safety under the poor operation of driver and vehicle.

Failure display for vehicle

Abstract: PROBLEM TO BE SOLVED: To easily recognize a failure by a driver while driving a vehicle even in the case of the occurrence of the failure in some of systems, in a vehicle mounting a plurality of the systems having a function different from each other. SOLUTION: As one example of a warning light 4a provided in a meter display 4, a trouble display A1 of a lane change support system, a failure display A2 of an all weather vision system, a failure display A3 of a driving support system, and a failure display A4 of a rear end collision foreseen system, are provided.

Technical report: physical and virtual passenger vehicle rollover crash tests: a literature review

Abstract: Rollover crashes have received more attention in recent years for several reasons. Though automotive manufacturers have improved the safety of their vehicles in the frontal, side and rear crash modes, rollovers remain a significant threat to vehicle occupants. Rollovers occur least often of all crashes, but their fatality rate is second only to frontal crashes. Occupant safety in a rollover is a difficult challenge facing the automotive industry due to the chaotic and unpredictable nature of the crash. Current standards do not ensure occupants involved in a rollover will be safe. The search for a repeatable and accurate dynamic rollover test to be used for a new safety regulation is ongoing. The newest safety tool for consumers is an informational rating given to vehicle models by the National Highway Traffic Safety Administration (NHTSA) on the likelihood of a vehicle rolling over if a crash takes place. Researchers have been studying the dynamics of rollover crashes, and simulation has become an important tool in understanding this crash mode. As technology gets more and more advanced, the simulations have become more accurate and useful. The newest technology available to aid in safety research of all types is finite element (FE) analysis software. Full frontal, side, and rear crash tests have been performed and validated in FE software, however a full rollover model has yet to be published.

Rear-end collision avoidance device for vehicle

Abstract: PROBLEM TO BE SOLVED: To assure a safety in rear-end collision while suppressing a cost increase. SOLUTION: This rear-end collision avoidance device for a vehicle comprises a traction control system and an electronic control brake system 8 controlling a service brake. The device also comprises a range measurement means for measuring a distance between the vehicle and a forward object, a vehicle speed detection means, a forward object speed calculation means, a deceleration calculation means for calculating a deceleration by using the distance from the forward object and the speed of the forward object, a safe braking distance calculation means, a rear-end collision avoiding manual operation judgment means, and a means transmitting a signal to instruct the no-load state of the engine to the traction control system, and a required calculated deceleration value is transmitted, as a brake requirement value, to the electronic control brake system, if a rear-end collision avoiding manual operation is not performed when the distance from the forward object is less than a safe braking distance.

Method for moving a headrest in the event of a rear-end collision and arrangement of a headrest on a vehicle seat

Abstract: The invention relates to a method for moving a headrest of a vehicle seat in the event of a rear-end collision and to an arrangement of a headrest on a vehicle seat. According to the invention, the headrest (3), in the event of a rear-end collision, can be moved in a forward direction of travel (Y) by means of a drive device (4) and by an impact device (5) that absorbs a rearward movement of the upper body of an occupant located on the vehicle seat (1).

Vehicle rear end collision preventing device

Abstract: PROBLEM TO BE SOLVED: To provide a vehicle rear end collision preventing device capable of applying brakes to the driver's own vehicle with a proper strength and at a proper timing upon acquiring the information on the foregoing vehicle including its braked condition SOLUTION: The vehicle rear end collision preventing device is composed of a distance measuring device 1 to measure the inter-vehicle distance between driver's own vehicle A and the foregoing vehicle B, a communication device 2 to receive the running information including the start of braking operation and deceleration of the foregoing vehicle B sent therefrom, a warning device 3 to emit a warning of rear end collision upon acquiring the inter-vehicle distance and running information and judging the possibility of rear end collision to the foregoing vehicle B from the acquired information and the running speed of the driver's own vehicle A, and an automatic brake device 4 to apply brakes to the driver's own vehicle A so that its deceleration becomes greater than that of the foregoing vehicle B in case there is such possibility of rear end collision Thereby the brakes are applied to the driver's own vehicle A with a proper strength and at a proper timing by getting the running information including the braked condition of the foregoing vehicle B

Car body structure of automobile

Abstract: PROBLEM TO BE SOLVED: To enhance transmission of load to front and rear sides of a car body and to realize energy absorption efficiency against front or rear end collision. SOLUTION: When a collision input is axially applied to a front waist reinforce 1 by a front collision, a load is transmitted to a door waist reinforce 6 through a front pillar 2 and is transmitted from the door waist reinforce 6 to a floor-constituting body 7 through a center pillar 5. Thereby, the load is dispersed and transmitted to a whole rear part of the car body.

Rear-end collision impact buffer device

Abstract: PROBLEM TO BE SOLVED: To provide a rear-end collision impact buffer device capable of restricting a damage of a cab of a colliding vehicle to the minimum, absorbing an impact in response to an impact force in a wide rang, and reducing an occupation space in the collision direction. SOLUTION: This rear-end collision impact buffer device 1 is provided in the rear part of a vehicle 2 to be collided at a height nearly corresponding to a chassis 12 of the colliding vehicle 11 to buffer the impact generated when colliding. This rear-end collision impact buffer device 1 is provided with a plurality of buffer materials 3a-3e arranged in the collision direction, and the top surface of each buffer material 3a, 3b, 3c arranged close to the colliding vehicle 11 is formed lower than the top surface of a front buffer material. A damage of a structural member (a cab 13) on the chassis 12 of the colliding vehicle 11 can be thereby reduced. A impact in a wide range can be absorbed by giving different strength to each buffer material 3a-3e, and a space in the collision direction can be saved.

Prealarming signal lamp and tail part of motor vehicle for preventing rear end collision

Abstract: The utility model relates to an alarm indication light for vehicle anti-bumping equipped at the tail portion of the vehicle The added alarm indication light of the utility model based on the existing technique is respectively connected with a capacitor, an electric resistance, a three-electrode tube and a relay Owning to the additional arrangement of the utility model of a set of alarm indication devices to the braking indication light of a vehicle, as long as in driving time of the diver, the accelerator pedal is unleashed, and before braking is adopted, the alarm indication light equipped at the tail portion of the vehicle can illuminate in advance When seeing the alarm indication light that the front vehicle illuminates, the rear driver should unleash the throttle immediately, and prepare for adopting braking, thereby vehicle bumping accidents can be avoided or decreased