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An alternative to the current drum brakes, with the increased requirements of todays daily service are disc brakes, in that they offer, in contrast to the drum brakes, the following technical advantages and in turn enhance the active safety of modern commercial vehicles when braking: Enhanced brake pedal-feedback and actuation Improved efficiency Little performance losses when high thermal loads occur (fading). In order to be able to determine the improvement potential of disc brakes they will be compared to the commonly employed Simplex drum brakes. Both wheel brake systems (disc-/drum brakes and all variations) were tested on a computer controlled brake dynamometer and in field tests using a heavy duty commercial vehicle (class 8). The results are compared and conclusions drawn regarding “advantages/disadvantages”.

The current trend toward electronic system integration will soon bring active and passive safety systems together inside a single electronic control unit. The processing capability of microcontrollers and digital signal processors make it feasible to integrate many systems together on a single chip or fewer chips than before. Increased integration however, can increase the consequences and reactions to common mode failures. Failure mode management associated with this type of integration will be critical to provide the expected benefits while balancing the failure effects on these traditionally isolated systems. This paper examines tradeoffs that can occur when various active and passive safety systems are integrated together. Alternative designs are compared and the effects of various failure modes are analyzed.

To maintain standards, all manufactured automotive items are subject to strict quality control. Quality control processes test items against agreed upon specification limits. Items that “pass” these tests are "good enough" for commercial use, while items that “fail” are discarded. Quality control testing for large numbers of manufactured products can be costly; as a result, manufacturers might implement inexpensive test processes. Less expensive test processes may result in lower accuracy measurements. Utilizing lower accuracy measurements can increase both the number of discarded items and the number of returned (or recalled) items. We have created a multi-dimensional statistical ellipse model, formed from both lower and higher accuracy measurements, with which the impact of decisions based on lower accuracy test procedures can be assessed. A common method used to improve production yield is to shift the specification limits, increasing the process’s capability index.

Given the legal requirements for quality assurance of passenger car exhaust emissions worldwide we define our quality assurance system and present the emission laboratories of the Mercedes-Benz assembly plants Sindelfingen and Bremen. We developed a hierarchically structured, multi-level computer system, which enables us to automize emission test procedures, calibration, maintenance of measurement systems and documentation of exhaust data. Test cell computers coordinate the different components of the test cells and perform maintenance and calibration of measurement devices, thus guaranteeing a high measurement quality with reasonable economy. The coordinating level computer, the emission host system (EHS), processes test parameters, controls and supervises the test sequences and evaluates the test results on a statistical basis.

The purpose of this research was to present and analyze a previously unreported mechanism of injury within the automotive crash environment - spinal burst or compression fractures due to a vertical force component. Spinal burst fractures are comminuted fractures of the vertebral body which are often associated with retropulsed bone fragments into the spinal. Compression fractures are less traumatic fractures of the vertebral body with minimal comminution. Both fracture types can have varying degrees of neurologic deficit. The mechanism of injury is hypothesized to be a high energy compressive load along the axis of the spine initiated through the buttocks and pelvis or through torso augmentation (inertial loading of the lumbar spine by the torso). Four crashes are presented as evidence of this injury mechanism within the automotive crash environment: two in the United States and two in Germany.

In the world of automated driving, sensing accuracy is of the utmost importance, and proving that your sensors can do the job is serious business. This is where ground-truth labeling has an important role in Autoliv’s validation process. Currently, annotating ground-truth data is a tedious and manual effort, involving finding the important events of interest and using the human eye to determine objects from LiDAR point cloud images. We present a workflow we developed in MATLAB to alleviate some of the pains associated with labeling point cloud data from a LiDAR sensor and the advantages that the workflow provides to the labeler. We discuss the capabilities of a tool we developed to assist users in visualizing, navigating, and annotating objects in point cloud data, tracking these objects through time over multiple frames, and then using the labeled data for developing machine learning based classifiers.

Advances in electronic technology have enabled significant enhancements to automotive safety in the last two decades. In the 1990's, death and injury rates declined significantly thanks to airbag/restraint and anti-lock braking systems. Governments and insurance industries tend to focus/legislate performance for the most severe accident types, since these accidents cause a disproportionate number of deaths1. The industry tends to emphasize performance on the severe events without realizing the potential drawbacks, especially at the other end of the scale in low severity events. This uneven approach can lead to overly sensitive systems that respond inappropriately in low severity events. This paper outlines the need to avoid industry ratings and government requirements that emphasize performance only at one end of the scale.

Far-side kinematics and injury are influenced by the occupant environment. The goal of the present study was to evaluate in-vehicle human far-side kinematics, kinetics and injury and to assess the ability of the WorldSID to represent them. A series of tests with five Post-Mortem Human Subjects and the WorldSID were conducted in a vehicle-based sled test environment. The surrogates were subjected to a far-side pulse of 16.5 g in a 75-degree impact direction. The PMHS were instrumented with 6 degree-of-freedom sensors to the head, spine and pelvis, a chestband, strain gauge rosettes, a 3D tracking array mounted to the head and multiple single 3D tracking markers on the rest of the body. The WorldSID lateral head excursion was consistent with the PMHS. However, forward head excursion did not follow a PMHS-like trajectory after the point of maximum lateral excursion. All but one PMHS retained the shoulder belt on the shoulder during the entire test.

Cyclist injuries and fatalities are a world-wide concern and often a consequence of interaction with cars. The MICA2 Project (Modelling of Interactions between Cyclists and Automobiles) is aimed at protecting bicyclists from getting injured by a passing car. This study addresses the need for new protective safety systems through the development and testing of a novel external car airbag. The airbag was designed to add protection to the center side part of the car, in the B-pillar area, to protect the head of a bicyclist impacting a car in this area. Two methods were used to evaluate performance of the system. For full system tests, a Hybrid III 50th percentile male dummy was seated on a city bike and projected into the side of a car at either 30°, 60° or 90° to the car side. In additional component tests an adult pedestrian headform was launched towards the roof rail or B-pillar structure of the car.