Motorcyclist Head Research Articles

Analysis head injuries of Vietnamese motorcyclist without a helmet in car to motorbike frontal impact using a computer model

Nowadays, with the increasing demand for travel, the number of people using motorbikes is increasing, especially in Vietnam. People tend to face more injury risks when they are in traffic, such as vulnerable road users (VRU) – pedestrians, cyclists, and motorcyclists. Therefore, the objective of this study is to assess how car crashes influence Vietnamese motorcyclists' bodies, in particular their heads, because they are the most vulnerable parts of their bodies. The result of this study is to let people know what they’re facing in case they are hit by a car. In addition, this research analyzes the injury to the motorcyclist's head when being hit by different configurations of the car. Due to the lack of facilities, car-to-motorcyclist frontal impact simulation has become the best way to resolve this problem. The impact conditions, which were obtained from real motorcyclist accidents in Vietnam, including the speed of vehicle and motorcycle, and impact angle, were defined as initial loading conditions in a simulation of the head striking the windscreen by using a finite element Vietnamese dummy model. Logistic regression models were developed to study brain injury risk with respect to injury-related variables: the head linear acceleration and head injury criterion (HIC) value. In this paper, the deformation of the motorbike structure model was neglected, so the material has been selected as a rigid form. The knowledge from this research could be a prerequisite for developing guidelines to improve motorcyclist safety in Vietnam.

Influences of impact scenarios and vehicle front-end design on head injury risk of motorcyclist

Motorcycle to vehicle collision is one of the most common accidents in the world and usually leads to serious or fatal head injuries to motorcyclists. This study aims to investigate the influences of impact scenarios and vehicle front-end design parameters on head injury risk of the motorcyclist. Five general vehicle types and different impact scenarios were selected for a parametric analysis. Impact scenarios were set according to ISO, 13232 regulation considering impact angles and impact speeds. Five vehicle types of Sedan, MPV (Multi-Purpose Vehicle), SUV (Sport Utility Vehicle), EV (Electric Vehicle) and 1-Box vehicle were included. HIC15 (Head Injury Criterion), head angular acceleration and CSDM (Cumulative Strain Damage Measure) were calculated to evaluate head injury risk of the motorcyclist. The results show that the critical impact speed for HIC15 and head angular acceleration was around 15 m/s, while the critical speed for CSDM was approximately 10 m/s. Impact angle of 45° show extremely high injury risk to the motorcyclist head. Bonnet leading edge height and its combination with other parameter present high influences on motorcyclist head injuries, and the increasing the bonnet leading edge height can potentially reduce head injury risk of motorcyclists. In summary, the present research results provide some theoretic bases for determining the test speed in motorcycle-vehicle crash regulation and design consideration for typical vehicle front end shape.

A study on motorcyclist head reponses during impact against front end of vehicle

Motorcycle to vehicle impact accidents occur frequently in real world and often cause serious brain injuries and deaths of motorcyclists. This study aims to research the motorcyclist head responses and helmet protection performance at common motorcycle-vehicle impact scenarios. First, multi-body system (MBS) models of motorcycle-vehicle impact were developed to investigate motorcyclist’s head and vehicle conditions (position, orientation and velocity) at the time of head impacts with vehicle. Then, the impact conditions were input to finite element (FE) models of head striking vehicle to obtain the head tissue level responses, such as coup pressure, von Mises stress, first principal strain and skull stress. Influences of impact velocity, impact angle, and helmet usage on head responses were investigated by conducting parametric studies. The results show that motorcycle and vehicle initial speeds and impact angles influence motorcyclists’ head impact locations on vehicles and head responses. Coup pressure and skull stress have strong relationships with head impact forces, while von Mises stress and first principal strain are sensitive to head equivalent impact velocity combining of normal and tangential velocities. Helmet shows a clear effectiveness in reducing brain pressure and skull stress, while its influences von Mises stress and first principal strain in brain subtly.

Automatic Detection of Motorcycle on the Road using Digital Image Processing

Traffic accident is one of the causes of death in the world. One of them is traffic accidents on motorcyclist not wearing helmets. To overcome this problem, several researchers have developed detection system of motorcyclist not wear helmet. This system consists of motorcycle detection and motorcyclist head detection. On motorcycle detection, accuracy still needs to be improved. For this reason, this paper proposed motorcycle detection by adding image improvement processes that are enhancing contrast and adding object positioning features.The techniques proposed in this study are divided into 3 stages of image enhancement, feature extraction, and classification. The image enhancement stage consists of enhance contrast, convert RGB image to gray scale, background subtraction, convert gray scale image to binary, closing operation, and small object removal. The features used in this paper are the features of the object area, the circumference of the object, and the location of the object, while the method for classification process using back-propagation neural network and SVM. The proposed method resulted in an accuracy of 96.97%. Error occurs in all image test data not motorcycle objects detected as motorcycle objects. This error is caused because the pixel value between the objects in the image with the background color has a level of difference is too small, so it is detected as an object not a motorcycle.

A STUDY ON MOTORCYCLISTS HEAD INJURIES IN CAR–MOTORCYCLE ACCIDENTS BASED ON REAL-WORLD DATA AND ACCIDENT RECONSTRUCTION

Accident data had shown that as one of the most vulnerable road users, the risk of motorcyclist casualties due to head injuries is extremely high in motorcycle accidents. The objective of this study was to analyze motorcyclist head injury based on epidemiological statistical analysis and car–motorcycle accident reconstruction using real world accident data, and obtain a comprehensive understanding about safety effects of helmets on motorcyclists head injury. In epidemiological data analysis of this study, odds ratios (ORs) was applied to identify differences in injuries between helmeted and unhelmeted motorcyclists. Two vehicle–motorcycle collisions with detailed information were reconstructed by using PC-Crash simulation and MADYMO reconstruction. Furthermore, the head injury reconstruction using MADYMO outputs as boundary conditions was accomplished and analyzed with respect to 1st principal strain, Von Mises stress, coup pressure, countercoup pressure at the cerebrum. The results indicated that unhelmeted motorcyclists were more likely to suffer head injury, serious and fatal injury, and tend to take equal responsibility or more. 1st principal strain was reduced from 0.44 to 0.25 for Case 1, and from 0.16 to 0.10 for case 2 when including a helmet. Von Mises stress were reduced from 30.37[Formula: see text]kpa to 19.51[Formula: see text]kpa for Case 1 and from 3.42[Formula: see text]kpa to 3.03[Formula: see text]kpa for case when including a helmet, which meant a reduction of the risk of concussion. But the motorcyclist in Case 2 experienced a lower percentage increase in coup pressure and countercoup pressure. This study provided comprehensive knowledge on motorcyclists head injuries and the effectiveness of helmets as well as contributing to develop the injury prevention measures and protection devices of motorcyclists.

Comparison of potential injuries to the head and lower extremities of a motorcyclist during impact with W-beam and wire rope barriers using FE simulations

ABSTRACTBecause of their lack of protection, motorcyclists are at a higher risk of injury during a crash compared to car occupants and contribute significantly to the road trauma around the world. Roadside barriers are constructed to protect riders from crashes with off-road objects. Among the different types of roadside barriers, the most common is W-beam barriers, which are designed in consideration of the safety of car occupants. Wire rope barriers may be installed as an alternative and have been found to be safe for cars. However, no in-depth investigation of injuries sustained by motorcyclists crashing into these barriers has been reported. The present study aims to investigate and compare potential injuries to a motorcyclist's head and lower extremities during collisions with W-beam and wire rope barriers. To capture the effect of structural stiffness, detailed finite-element (FE) models of the rider (dummy), the motorcycle, and the barriers were used in simulations carried out in LS-Dyna®, an explicit FE solver. The wire rope barrier was found to be capable of restraining the rider on the road in all cases. Although injuries to lower extremities increased in some cases, potentially fatal injuries to the rider's head were reduced by the wire rope barrier.

Designing and Constructing a Smart Armor for Protecting Motorcyclists’ Head and Neck in the Accident Time

Background: In general, riding motorized two-wheeled vehicles carries a higher risk of being involved in a fatal accident than any other mode of transport. In some countries, the use of protective helmets while riding motorcycles is a legal requirement. That is, a helmet can be a lifesaver in an accident and can protect against severe head, brain and facial injuries, particularly integral helmets with full facial protection. The present paper introduces a newly invention of smart armor to protect motorcyclist's head and neck in an accident time and to minimize injuries. Materials & Designs: The smart armor for protecting motorcyclist's head and neck was designed innovatively. The system was constructed from boxes settled on the motorcycle, including a power source, an incident detection sensor, a transmitter circuit and a transmitter circuit antenna. In addition, the helmet parts including a mechanical operator's box, mechanical force interface cables, helmet frame, balance surface, fixed neck guard and moving neck guard were constructed. The constructed system was formally registered by the Iranian Patent Organization in 2010. Findings & Tests: The smart armor showed useful capabilities and was successfully tested by several motor cyclists in simulated accidents. The different mode of collision with obstacle ahead, back hit, and change angle more than 45 degrees from vertical mode of motorcycles were successfully tested. Conclusions: The designed smart armor presented in this article, showed a suitable performance to protect motorcyclist's head and neck simultaneously. Therefore, it can be used as a suitable protective device for motorcycle riders.

Behaviour of helmets during head impact in real accident cases of motorcyclists

A motorcyclist is a vulnerable road user and the most often injured body segment is the head. The present study deals with motorcyclist's head protection and is focused on the behaviour of the helmet during simulated head impact in real accident cases. The analysis of real-world motorcyclist head trauma can be divided into three steps, i.e. accidentology to collect several real accident cases, kinematics reconstruction to obtain the initial conditions of the head just before the impact and helmeted head impact simulation to evaluate the behaviour of the helmet during impact and to assess the head injury risk. For each accident case, body kinematics has been simulated using MADYMO software. The initial condition, in terms of velocity and impact location, of the head just before the impact was then extracted and implemented in the finite element model of the human head coupled with a validated finite element model of a helmet in order to reconstruct the head impact. This impact analysis on the helmeted head allowed us to highlight the injury mechanisms specific to motorcyclists especially in terms of helmet and head loading. In this study, the relative velocities between head and impacted structure vary from 25 to 60 km/h with significant tangential components. The deformations of the constituting helmet's material vary from 17% to 90% for this rather low-energy impacts, demonstrating that improvement in material behaviour is needed in order to increase survival chances in the case of impact speeds above 30 km/h.

Influence of the body on the response of the helmeted head during impact

The most frequent type of injury that causes death or disability in motorcycle accidents is head injury. The only item of personal protective equipment that protects a motorcyclist's head in real-world accidents is the safety helmet. The protective capability of a helmet is assessed, according to international standards, through the impact of a headform fitted with the helmet onto an anvil. The purpose of the present work was to study the influence of the presence of the body on the impact response of the helmeted head. Full-body and detached-head impacts were simulated using the finite element (FE) method. As a consequence of the presence of the body, the crushing distance of the helmet liner was drastically increased. This evidence indicated that the effect of the body should be included in impact absorption tests in order to provide conditions that are more realistic and stringent. The solution to an analytical model of the helmeted headform impact revealed that increasing the headform mass has the same influence on impact outputs, particularly the liner's crushing distance, as including the whole body in impact tests. The added mass was calculated by using a helmeted Hybrid III dummy for an impact configuration that frequently occurred in real-world accidents.

Head and neck responses in oblique motorcycle helmet impacts: a novel laboratory test method

The dynamics of a Hybrid III dummy's head and neck in helmeted impacts using a novel oblique impact test were studied. Three impact conditions were investigated that simulated a range of motorcyclist head impacts and provided estimates of head and neck injury using published injury assessment reference values. The resultant linear and angular accelerations in the coronal plane were significantly higher for an impact to the side of the head when compared with frontal impacts. Neck axial forces were recorded, ranging from 2.1 to 3.4 kN. Linear regression analyses were conducted to determine the correlation coefficients that characterised the relationships between dummy responses and impact and sled velocities. Linear regression curves showed that increasing the impact and sled velocities resulted in an increase of the head angular accelerations. The neck axial force was found to positively correlate with the impact and sled velocities in the lateral impacts.

FEA of oblique impact tests on a motorcycle helmet

In accidents, motorcycle riders full-face helmets often make oblique impacts with road surfaces. Finite element analysis was used to predict the rotational and linear acceleration of a Hybrid II headform, representing a motorcyclist's head, in such impacts, considering the effects of friction at the head/helmet and helmet/road interfaces. Simulations of the oblique impact test in British Standard BS 6658 were validated by comparison with published data. This showed that COST 327 experimental data was largely determined by the friction coefficient (0.55) between the helmet shell and abrasive paper, and hardly affected by that between the head and helmet. Slip was predicted at the shell/paper interface throughout the impact, due to the high angular inertia of the helmet, and the normal force remaining below 3.5 kN. Simulations of more severe motorcycle helmet impacts explored the effects of impact site and direction, impact velocity components, helmet fit and the scalp. In these impacts, the higher velocity component normal to the road caused high frictional forces on the helmet shell, eventually causing it to roll on the road. The peak headform rotational accelerations, at some impact sites, were potentially injurious. The most effective method of reducing head rotational acceleration could be a reduction in the linear acceleration limit of the helmet standards.

The effects of a mandatory motorcycle helmet law on helmet use and injury patterns among motorcyclist fatalities

Background The National Highway Traffic Safety Administration (NHTSA) has found that motorcycle helmets are 37% effective in preventing death and 65% effective in preventing brain injuries in a crash. Unfortunately, in 1995 Congress lifted federal sanctions against states without helmet laws and since then there have been a number of primary motorcycle helmet laws repealed or weakened. More lives could be saved and serious injuries avoided if there was increased helmet use throughout the United States. Methods This study analyzed helmet use and injury patterns among motorcycle riders in the United States involved in fatal crashes from 1995 through 2003 and compared the results between states with and without a primary helmet law. Age, sex, injury severity and helmet use are some of the variables obtained from the Fatality Analysis Reporting System (FARS). Results In the 20 states and the District of Columbia, which currently have a primary helmet law, 84.0% of fatally injured riders were wearing a helmet. In the 27 states with a secondary helmet law, 36.2% of fatalities used a helmet, and in the remaining three states with no law at all, helmet use dropped to 17.6%. In the two states (Arkansas and Texas) that changed from a primary helmet law to a secondary helmet law in 1997, helmet use decreased from 78.2% in 1996 to 31.7% in 2000. Conclusion If all states were to enact a primary motorcycle helmet law, helmet use would dramatically increase while decreasing the number of motorcyclist head injuries and fatalities. Impact on Industry The results of this study will hopefully persuade law makers to enact primary helmet laws in all states throughout the nation. Helmet manufacturers can use this data to design more comfortable helmets while also improving upon the protective qualities of these safety devices.

Evaluating the Positional Stability of Motorcycle Helmets

Traditional motorcycle helmet performance standards provide a test for the strength and stiffness of the retention system. While such tests assure adequate strength, they do not assure that the helmet will be retained in place on a motorcyclist's head, even when securely fastened. The reason is that the geometry of the retention system can allow the helmet to roll off when contact or inertial forces are generated in a collision. This ejection of motorcycle helmets during accident events has been widely noted by various researchers. Different types and styles of motorcycle helmets were tested to determine the susceptibility to roll off, i.e. “positional stability”. Tests were performed with two commonly used adult sizes of headforms corresponding to standards of the U.S. Department of Transportation (DOT) and the International Standards Organization (ISO). The laboratory test results were validated by comparable tests on one hundred human subjects. The results of the human subject tests show a meaningful relationship to the laboratory test that employs a 10kg mass dropped 60cm to jerk the helmet forward to cause it to roll off. The results show that the geometry of the helmet retention system has a powerful effect on the ability of the helmet to resist forward roll off in both laboratory and human subject tests. Also, there is considerable difference in the retention characteristics between DOT and ISO headforms, with the DOT headform more closely corresponding to human subject data.