Finite element modelling of metallic tubular crash structures with an explicit code

Numerous experimental studies have been carried out to investigate the collapse of tubular metallic crash structures under axial compression. Some simple theoretical models have been developed but these often assume one type of progressive collapse, which is not always representative of the real situation. Finite Element (FE) models, when further refined, have the potential to predict the actual collapse mode and how it influences the load-displacement and energy absorption characteristics. This paper describes an FE modelling investigation with the explicit code LS−DYNA. An automatic mesh generation programme written by the authors is used to set up shell and solid element tube models. Mesh specification issues and features relating to the contact and friction models are discussed in detail. The crush modes, load-deflection characteristics and energy absorption values found in the simulations are compared with a reasonable degree of correlation to those observed in a physical testing programme; however, improvements are still required.

Intelligent headrest

In this paper we discuss the design and development of a novel intelligent headrest system. Developed to reduce neck injuries resulting from up to 63% of rear end accidents, this system uses inductive sensing technology to establish the position of a driver or passenger's skull in a vehicle. Once detected, the system autonomously places the vehicle's headrest in a position that best support an occupant's head in the case of an accident. Sensor construction, mechatronic design and controller selection and real world tests of the system under various conditions are covered.

Vehicle design for minimum societal harm

A design technique was developed to provide the best protection to all occupants in the real-world crashes that occur on Australian roads. A team of experts from around the world was marshalled to analyse crash data, develop new information on impact injury and a new computer optimising technique for simulation of side impact crashes.

"Tomorrow's car" : Deakin Universities new cross vehicle that combines the best of 2 worlds

Motorbike riders are 34-times more likely to die in a crash compared to car drivers per km travelled (1). Such safety risks together with special skill requirements for the driver and much lower comfort compared to normal cars are the main reasons why motorbikes represent only a fraction of all vehicle sales in developed countries. Deakin University is developing a revolutionary cross-over fun vehicle with ultra low fuel consumption and emissions. This new vehicle generation combines the best of two worlds: the fun to drive, low cost, and small size of a scooter together with the safety, comfort and easiness to operate of a car. The result is a vehicle that is more fuel efficient than most cars or even scooters.

Various tilting cross over vehicles have been presented over the last decade that were trying to automate the tilting control of narrow vehicles to make them safer. Examples of these concepts are the Carver, Clever and in some way also the MP3 scooter from Piaggio. The problem with fully enclosed concepts like the Carver or Clever is that they require very complex and therefore also expensive tilting control systems so that the vehicles are not price competitive compared to low cost micro cars or even normal small cars. The MP3 on the other hand comes with a tilting control system which is only semi automatic so that typical car advantages - comprehensive safety features like crush zones, roll over protection, air bags, safety belts or comfort features like full weather protection including heating and cooling – can not be provided.

Deakin’s approach is quite different to the above mentioned concepts. The requirements were derived based on two different investigations: The first step was a critical evaluation of social trends and the second step was an in-depth benchmarking study of existing concepts which identified the typical strengths and weaknesses of these concepts. In a critical next step a new concept was created that addresses most of the weaknesses of existing tilting three-wheelers in a holistic approach by setting clear priority rankings for the vehicle targets, based on current trends. The priorities were set in the following order: Safety, Affordability, Fun and Efficiency (SAFE).

The key feature that enables an enclosed tilting vehicle is a fully automatic tilting control system. With an automatic tilting control system the driver does not need to put the feet on the ground to balance the vehicle when he stops, so the vehicle can be built with a full enclosure. This allows the implementation of typical car like safety features (seat belts, roll over structure, crush zones, air bags). The SafeRide™ tilting control system is a passive system that involves the driver’s balancing sense in its feedback control system. The vehicle has typical scooter like steering characteristics, where the steering is initiated through countersteering. Another safety critical design feature is the crush zone between the two front wheels which is not possible with only one front wheel or with the powertrain positioned between the front wheels, as the powertrain can’t absorb a lot of energy due to its structural stiffness and density. The passive tilting control system is quite simple and therefore makes the vehicle very affordable, an important factor for successful commercialisation.

Another advantage of integrating the human balancing senses in the feedback control of the tilting system is that the system kicks in slightly after the human balancing reacts. In some instances that can generate the typical adrenalin thrill known from riding a bike. This fun factor is quite common with many trend sports like mountain biking, surfing, roller-skating, snowboarding, or skateboarding. Some of these sports have seen very rapid growth only a short time after they have been invented. Utilising the human balancing system during driving also makes the vehicle safer as the adrenalin is produced after reaching a semi-stable driving condition that is controlled by the vehicles tilting control system, but before the vehicle reaches an unstable driving condition that can not be controlled by the vehicle but only (eventually) by the driver – if he has got the required driving skill and if he is alert enough.

Efficiency superior to most cars and scooters is achieved by the aerodynamics of a fully enclosed body structure in combination with the small frontal area of a typical scooter and the droplet shape enabled by the relatively wide front with 2 wheels and the very narrow tail with only one rear wheel. The passive tilting system also contributes to the extreme efficiency as the system only draws some small electrical power for the electronic control unit. Another feature is a low cost exhaust energy recovery system which is discussed in another paper.

Occupational light vehicle-use: a research driven strategy to improve surveillance and inform policy

Background: Occupational light vehicles (OLV) are light passenger and loadshaped vehicles used for work. The OLV-associated injury burden is as great as that of heavy vehicle users, but has been largely ignored by occupational health and safety (OHS) regulators. Contingent employment growth has accentuated existing gaps in the policy framework between OHS and road-safety. Frequent burden shifting from OHS to road-related health systems undermines the evidence base necessary to inform policy development. Aims: To provide evidence-based recommendations for the collection of OLVuser surveillance data and to underpin OHS procedures and policies for OLVusers. Method: The literature was systematically analyzed to identify OLV-user OHS policy and practice gaps. Strategies to improve and co-ordinate surveillance systems were developed to address the identified limitations. Results: Gaps were identified in OLV-user legislation, data collection, and riskmanagement. These require strategies to improve identification of all OLV-users and to co-ordinate surveillance and OHS practice. Discussion: Contemporary reform of road and OHS, policy, provides a timely opportunity for the implementation of strategic responses to this serious road safety and occupational, public health problem.

Occupational light vehicle use: characterising the at-risk population

Previous occupational light vehicle research has concentrated on employees using cars. The aim of this study was to identify and characterise the total occupational light vehicle-user population and compare it with the privately-used light vehicle population. Occupational light vehicle and private light vehicle populations were identified through use-related 2003 registration categories from New South Wales Roads and Traffic Authority data. Key groups of occupational light vehicle registration variables were comparatively assessed as potential determinants of occupational light vehicleuser risks. These comparisons were expressed as odds ratios with 95% Confidence Intervals. The occupational light vehicle population vehicles (n=646,201) comprised 18% of all light vehicle registrations. A number of statistical differences emerge between the two populations. For instance, 86% of occupational light vehicle registrants were male versus 65% of private registrants, and 56% of the occupational users registered load shape vehicles versus 20% of the private registrants. Occupational light vehicles registered for farming or taxi use were more than six times more likely to belong to sole-traders than organisations. Sole-traders were nearly twice as likely to register light-trucks, and twice as likely to register older vehicles, than organisations. This study demonstrates that the occupational light vehicle user population is larger and more diverse than previously shown with characteristics likely to increase the relative risks of motor vehicle crashes. More occupational light vehicles were load shapes and therefore likely to have poorer crashworthiness ratings than cars. Occupational light vehicles are frequently used by sole-traders for activities with increased OHS risks including farming and taxi use. Further exploration of occupational light vehicle-user crash risks should include all vehicle types, work arrangements and small ‘fleets’.

Estimating fatality rates in occupational light vehicle users using vehicle registration and crash data

Objective: To estimate occupational light vehicle (OLV) fatality numbers using vehicle registration and crash data and compare these with previous estimates based on workers' compensation data. Method: New South Wales (NSW) Roads and Traffic Authority (RTA) vehicle registration and crash data were obtained for 2004. NSW is the only Australian jurisdiction with mandatory work-use registration, which was used as a proxy for work-relatedness. OLV fatality rates based on registration data as the denominator were calculated and comparisons made with published 2003/04 fatalities based on workers' compensation data. Results: Thirty-four NSW RTA OLV-user fatalities were identified, a rate of 4.5 deaths per 100,000 organisationally registered OLV, whereas the Australian Safety and Compensation Council (ASCC), reported 28 OLV deaths Australia-wide. Conclusions: More OLV user fatalities were identified from vehicle registration-based data than those based on workers' compensation estimates and the data are likely to provide an improved estimate of fatalities specific to OLV use. Implications: OLV-use is an important cause of traumatic fatalities that would be better identified through the use of vehicle-registration data, which provides a stronger evidence base from which to develop policy responses.

Regulation of motor vehicle advertising: toward a framework for compliance research

There is concern that certain content within some motor vehicle television advertising may negatively influence the driving attitudes and behaviours of viewers, particularly young people, and hence have a negative impact on road safety. In recognition of this concern, many developed countries have adopted a self-regulatory approach to motor vehicle advertising. The basic elements of self-regulation are a code of practice or guiding principles governing advertising content and the establishment of a process for hearing and adjudicating complaints about alleged breaches of that code. However, as in other areas, the effectiveness of self-regulation is being questioned in that many motor vehicle advertisements in Australia and elsewhere appear non-compliant with self-regulatory codes. Applying lessons from studies of alcohol advertising, this paper first reviews the research assessing the content of motor vehicle advertising. A suggested research framework is then proposed to inform the development of motor vehicle advertising regulatory codes where they do not exist, and to better monitor compliance with codes where they do exist. The research framework suggested includes expert content analysis of ads, the impact of advertising on risk-taking cognitions and decisions in computer-simulated traffic situations, and assessing audience perceptions of, and reactions to, messages in advertisements mapped against regulatory code content. An example of audience reaction research is also presented.

Vehicle motion simulators, a key step towards road vehicle dynamics improvement

Real road vehicle tests are time consuming, laborious, and costly, and involve several safety concerns. Road vehicle motion simulators (RVMS) could assist with vehicle testing, and eliminate or reduce the difficulties traditionally associated with conducting vehicle tests. However, such simulators must exhibit a high level of fidelity and accuracy in order to provide realistic and reliable outcomes. In this paper, we review existing RVMS and discuss each of the major RVMS subsystems related to the research and development of vehicle dynamics. The possibility of utilising motion simulators to conduct ride and handling test scenarios is also investigated.