Highway Safety Research Institute Research Articles

Development of a Motion Control for a highly dynamic, self-propelled driving simulator

The new concept of the self-propelled driving simulator comprises a hexapod, a yaw joint and a wheel-based motion platform with four individually steerable wheels. This concept provides a theoretically unlimited motion range, which especially enables highly dynamic drive maneuvers. To ensure an omnidirectional motion, the motion platform has to accelerate instantly in any direction. This requirement leads to the main challenges in the control system of the simulator: taking into account the nonlinear and transient tire characteristics and generating the target accelerations as expected by the driver. According to these requirements, the Motion Control is only for controlling the horizontal dynamics of the motion platform. The Motion Control presented in this paper includes various model definitions, especially regarding the essential tire characteristics considered within an extended HSRI (Highway Safety Research Institute) tire model. The Motion Control as Two-Degrees-of-Freedom control contains a Feedforward for generating target body forces, a Control Allocation for an optimal force distribution to the wheels, a Single Wheel Control as a specific control of the tire forces, and a Compensation Control on acceleration level. Investigation of this control by simulation, using a simplified reference model, already revealed a high controller performance regarding accuracy and quality. The optimal force distribution leads to an equal adhesion utilization and the Compensation Control compensates the remaining Single Wheel Control deviations. Difficulties only occur for the steering angle in the case of low velocity up to a standstill. Due to the exact input–output linearization, the Single Wheel Control leads to a singularity and instability. Therefore, the steering angle requires exceptional control in this case.

Big Data Interprets US Opioid Crisis

Since 2010, there has been a new round of drug crises in the United States. The abuse of opioids has led to a sharp increase in the number of people involved in drug crimes in the United States. There is an urgent need to explore solutions to the drug crisis in the United States. In this paper, the model of in-depth analysis is established under the condition of obtaining the opioid data and the influence factor data of the large sample of five state[1]. In the first part, we use the Highway Safety Research Institute model based on the differential equation model to predict the initial value, find the initial position of the drug transfer, and obtain the curve of the number of different groups over time by fitting the data, so that the curves can be predicted the changing trends of the groups in the future. It was found that in Kentucky State, the county’s most likely to start using opioids were Pike and Bale. In Ohio, the county’s most likely to start using opioids are Jackson and Scioto. In Pennsylvania State, Mercer and Lackawanna are the counties most likely to start using opioids. Martinsville and Galax are the counties where Virginia State is most likely to start using opioids. Logan and Mingo are the counties where West Virginia State is most likely to start using opioids. In the second part, the gray prediction model is used to further analyze the time series of each factor, the maximum likelihood estimation method is used to obtain the weight of each factor, and the weight coefficient matrix is used to simulate the multivariate regression equation, and the factors that have the greatest influence on opioid abuse are educational background and family composition. In the third part, the hypothesis test model of two groups (the data type is proportional) is used to verify the difference between the influence factors (including the predicted values) in the first two parts of the states, thus verifying the feasibility between them. At the same time, we put forward a few suggestions to combine the current situation in the United States with the CDC data. We believe that in order to address the opium crisis, the U.S. government needs to strengthen not only oversight of doctors' prescriptions, but also make joint efforts of all sectors of society to fundamentally reduce the barriers to the use of opioids.

Estimation of Road Friction Coefficient and Vehicle States by 3‐DOF Dynamic Model and HSRI Model Based on Information Fusion

AbstractVehicle states and the road friction coefficient in active safety control systems have become increasingly prominent. However, a low‐cost, high‐precision system in real‐time has yet to be achieved. The use of complex models has led to poor real‐time estimation, while variations in the road friction coefficient have often been neglected. This paper adopts information fusion technology by using DEKF theory for rapid simulation and estimation of these parameters. Using a vehicle dynamic model based on three degrees of freedom (3‐DOF) and the Highway Safety Research Institute tire model, DEKF recursive estimation models are established and verified. In the DEKF, two recursive state and parameter estimation models exist in parallel. The models are dependent upon each other and have real‐time interaction correction in order to forecast information, which quickly yields true value estimation in simulation. Experimental brake test results show that the DEKF estimator not only accurately estimates the vehicle state parameters, but also estimates the road friction coefficient in real‐time. This can reduce the cost of the vehicle sensor, and can estimate the status parameter, which is difficult to measure. The validity and feasibility of this algorithm have been verified by an HIL driving simulator, offering the possibility of future application in real cars.

Dual extended Kalman filter for combined estimation of vehicle state and road friction

Vehicle state and tire-road adhesion are of great use and importance to vehicle active safety control systems. However, it is always not easy to obtain the information with high accuracy and low expense. Recently, many estimation methods have been put forward to solve such problems, in which Kalman filter becomes one of the most popular techniques. Nevertheless, the use of complicated model always leads to poor real-time estimation while the role of road friction coefficient is often ignored. For the purpose of enhancing the real time performance of the algorithm and pursuing precise estimation of vehicle states, a model-based estimator is proposed to conduct combined estimation of vehicle states and road friction coefficients. The estimator is designed based on a three-DOF vehicle model coupled with the Highway Safety Research Institute(HSRI) tire model; the dual extended Kalman filter (DEKF) technique is employed, which can be regarded as two extended Kalman filters operating and communicating simultaneously. Effectiveness of the estimation is firstly examined by comparing the outputs of the estimator with the responses of the vehicle model in CarSim under three typical road adhesion conditions(high-friction, low-friction, and joint-friction). On this basis, driving simulator experiments are carried out to further investigate the practical application of the estimator. Numerical results from CarSim and driving simulator both demonstrate that the estimator designed is capable of estimating the vehicle states and road friction coefficient with reasonable accuracy. The DEKF-based estimator proposed provides the essential information for the vehicle active control system with low expense and decent precision, and offers the possibility of real car application in future.

Constitutive modelling of abdominal organs

Abdominal organs are very susceptible to trauma. In order to protect them properly against car crash and other impact consequences, we need to be able to simulate the abdominal organ deformation. Such simulation should account for proper stress–strain relation as well as stress dependence on strain rate. As the step in this direction, this paper presents three-dimensional, non-linear, viscoelastic constitutive models for liver and kidney tissue. The models have been constructed basing on in vivo experiments conducted in Highway Safety Research Institute and the Medical Centre of The University of Michigan ( Melvin et al., 1973). The proposed models are valid for compressive nominal strains up to 35% and fast (impact) strain rates between 0.2 and 22.5 s −1. Similar models can find applications in computer and robot assisted surgery, e.g. the realistic simulation of surgical procedures (including virtual reality) and non-rigid registration.

The University of Michigan, Highway Safety Research Institute, report UM-HSRI-82-9 : T. D. Gillespie, L. Segel, R. D. Ervin, L. W. Schneider and K. L. Campbell 1982

The University of Michigan, Highway Safety Research Institute, report UM-HSRI-82-9 : T. D. Gillespie, L. Segel, R. D. Ervin, L. W. Schneider and K. L. Campbell 1982

The University of Michigan Highway Safety Research Institute, US

The University of Michigan Highway Safety Research Institute, US

Annotated bibliography on highway travel exposure research methods : Arthur C. Wolfe. Report No. UM-HSRI-78-7. Prepared by the Highway Safety Research Institute, University of Michigan, for the National Highway Traffic Safety Administration, U.S. Department of Transportation, Washington, D.C., January 1978. 55pp (Available from NTIS.)

Annotated bibliography on highway travel exposure research methods : Arthur C. Wolfe. Report No. UM-HSRI-78-7. Prepared by the Highway Safety Research Institute, University of Michigan, for the National Highway Traffic Safety Administration, U.S. Department of Transportation, Washington, D.C., January 1978. 55pp (Available from NTIS.)

Impact trauma of the human temporal bone.

A cooperative study between the Department of Otorhinolaryngology and the Highway Safety Research institute of the University of Michigan was designed to study temporal bone fracture produced in cadavers subjected to realistic automotive impact situations. Utilizing sled and piston impact configurations frontal and parietal impacts were noted to produce ipsilateral and contralateral fractures of nine temporal bones in seven cadavers. The impact velocities varied between 18.1 and 25.0 mph. Using standard otologic microsurgical techniques, the temporal bones were dissected and numerous gross and microscopic injuries to middle and inner ear structures were found. The authors conclude that extensive comminuted fracture of the human temporal bone is seen with realistic crash situations of low velocity, and that lateral impact which produces a longitudinal fracture with a posterior fossa comminution is associated with disruption of the cochlea and facial nerve, as well as of middle ear structures. The classical transverse fracture of extensive skull trauma lies medial to these structures and does not involve the otologic contents of the human temporal bone. Associated brain and skull injuries are also described.

Safety for Children in Automobiles

In the current issue ofAmerican Journal of Diseases of Children(129:946-949, 1975) an article entitled, Are 1974-1975 Automotive Belt Systems Hazardous to Children? squarely faces the problem of trauma to childrenas a result ofusing restraint systems in automobiles. It decries the apparently widely accepted, but unsupported, belief that children should not wear safety belts, and asks pediatricians to report both injuries and cases in which restraints have been effective in preventing or reducing the severity of injuries. Since pediatricians often do not hear about children who wereuninjuredin a motor vehicle crash, it is hoped that other physicians who may hear about such incidents from adult patients would also report. (Physicians may write directly to Richard G. Snyder, PhD, Highway Safety Research Institute, Huron Parkway and Baxter Road, Ann Arbor, MI 48105, or to me at the AMA.) The need for data in regard to child

SEAT BELT INJURIES

Department of Anatomy, The University of Michigan Medical School, and the Biomedical Department, Highway Safety Research Institute, The University of Michigan, Ann Arbor

Research on Wet Tire Traction

Abstract This paper describes experiments and methodology employed in an attempt to develop a system for the grading of wet tire traction. Data from instrumented vehicle experiments and the University of Michigan Highway Safety Research Institute mobile tire tester are used to support the conclusions. The vehicle tests include J-curve cornering and diagonal, locked-wheel braking. The maneuvers are used to generate information on tire tractive properties and their dependence on tread depth, rim size, suspension, and surface conditions. Three tire force measures obtained with the mobile tire tester, the peak longitudinal, peak free-rolling lateral, and locked-wheel longitudinal coefficients of friction, are presented for a group of 90 percent of the original equipment tire sizes in use on American cars and are rank correlated with vehicle results. The results indicate the feasibility of defining minimum wet traction levels for various tire-road interface properties.

THE PREVENTION OF HIGHWAY INJURY. Proceedings of a Symposium, 1967

THE PREVENTION OF HIGHWAY INJURY. Proceedings of a Symposium, 1967 Ross A. McFarland CopyRight https://doi.org/10.2105/AJPH.59.6.1067 Published Online: August 29, 2011

Who Is the Deadly Drinking Driver?

Joseph W. Little, Assistant Professor of Law, University of Florida, was formerly associated as a full time researcher with the University of Michigan's Highway Safety Research Institute, and continues his affiliation as a consultant. Mr. Little is a graduate of the University of Michigan Law School and has practiced law in Atlanta, Georgia and Ann Arbor, Michigan. This paper was prepared as a result of his participation in a proposal to the National Highway Safety Bureau for a major Alcohol Safety research contract to the Highway Safety Research Institute, which has devoted special attention to the place of alcohol misuse in highway tragedies.-EDITOR.