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Safety-critical systems are systems that cannot be allowed to fail. Such systems, if they fail, may cause economic damage or even loss of life. As a result, bug-fixes and patches are routinely applied to traditional software. But such updates are rarely feasible in safety-critical systems. In this paper, we introduce how formal verification has been applied to verify safety-critical systems. We will also show how model checking can be used to unearth deficiencies in a system and then improve it, by applying it to an airbag system - which is one of the most common safety critical systems we use everyday. Finally we propose an improved design of such a system with added redundancy, that is more robust to faults.

To accurately characterize the large deformation and nonlinear characteristics of airbags, the influence of cord parameters on vertical force characteristics was studied, and a finite-element simulation model of airbags based on gas-solid coupling was established. First, uniaxial tension and compression experiments with airbag under different initial pressures were carried out to analyse the effects of the initial pressure and working height on the mechanical properties of the airbag. Second, the validity of the model was verified by the test data of the vertical force and cavity pressure of the airbag. Finally, based on the gas-solid coupling model proposed, the influence of the cord parameters on the vertical force characteristics was studied. The results show that the vertical force characteristics of an airbag are different between compression and tension and the nonlinear characteristic of the airbag becomes more obvious with the increase in the displacement in compression. After comparing the effects of cord parameters on the vertical force of the airbag, we can conclude that the number of cord layers has the most significant effect on the vertical force, followed by the cord diameter, while other cord parameters have a general effect. Under the same compression and tension displacements (d = ±80 mm), the effective area of 1 cord layer is 2.56 times as much as the effective area of 6 cord layers and the vertical force of the airbag with a cord diameter of 0.25 mm is 7.28 times greater than that of the corresponding vertical force with a cord diameter of 1.0 mm. The airbag with different cord angles shows differences in the working state of compression and tension, especially in compression. The force of the airbag at 90° cord angle gradually exceeds the force at other angles with an increase in displacement. The difference in the load at different working states of compression and tension is useful.

Because of the body function decline and the decreased reaction sensitivity, the old people’s falling accidents happen from time to time. Falling will cause physical injury and negative psychological behavior. It had an extremely adverse effect on the life of the old people and brought burden to family and society. In this paper, the femur model of human body was established by finite element method and the dynamic response of femur when human falling was analyzed. The protective airbag was designed according to the relevant size of human body, and the protective effect of air bag in falls was investigated. The results of finite element analysis showed that the stress of femur and the stress concentration is markedly decreased, the maximum impact force was reduced by 94% and the rate of impact force decreases when the femur was protected by the airbag, which proved the feasibility of the designed airbag.

An airbag automatic inflator was designed, which consists of a column pressure vessel, a bidirectional solenoid valve and a spherical airbag, etc. By introducing a thermodynamic model, its key parameters were analyzed and calculated according to the mass flow formula equation system. The numerical analysis models of the airbag with folding modes such as planar direct folding, symmetrical folding and roll folding were established to study the dynamic characteristics of the airbag inflating and unfolding, and the effects of the folding modes, the inflating rate and the inflating amount on the change of the curves of the volume and internal pressure of the airbag in the unfolding process were discussed respectively.

Squib Driver Unit deploys the airbag for passenger safety by igniting the squibs. The High Side (HS) driver provides regulated current for defined dwell times in order to ignite the squib with energy of 8mJ. This energy should be delivered only when the driver is powered. However dynamic shorts with slew rates of 100V/µs on the drain of the HS driver in its unpowered state can also provide 8mJ energy to the squib and inadvertently deploy the airbag if proper gate discharge is not present to ensure fast turn OFF of the HS driver. The HS driver proposed here regulates the current to 1.37A for 2.1ms and 2A for 0.75ms in the powered state with 0.4µJ energy limitation to prevent inadvertent deployment using passive and active discharge paths in the unpowered state. The leakage current from the drain of HS driver is 1µA at 35V when compared to prior Art of 50µA. This design is implemented and verified on a 4 loop squib driver in 0.35µm, 85V BiCMOS process.

Driver airbag (DAB for short) lightweight design is the inevitable trend of development. Based on the research of DAB development trend and design challenges, this paper studies the effect of lightweight design on the performance of DAB. In the paper, a project of Dong Feng Peugeot Citroen Automobile Company LTD (DPCA for short) DAB has been adopted as an example, some specific issues have been discussed. Then, the accordingly provide some designs and proposal verifications as well as some analytic ideas and design measures for the development of other DAB.

Motorcycles are an important part of daily transportation. They are specially used to avoid traffic congestions downtown and most of the individuals tend to use a motorcycle because it takes less time to get to the destination. The rapid increase of motorcycle usage has led to a significant increase in the number of motorcycle-related accidents and fatalities. The reasons for accidents which were considered are speeding, collision with objects, lack of focus or drowsiness where only the rider's head is protected but not the body. And accidents may lead to death when help is not called immediately. By considering these, author introduces a Motorcyclists Safety Assistant Application (MSAA). This research tries to address four major factors that caused most road accidents and fatalities in Sri Lanka. They are excess speed, 360-degree threat detection, motorcyclist safety balloons, and emergency alert system. Here, MSAA can detect the vehicle's real-time speed and inform the user when a certain speed limit has been exceeded. Also, it has proposed a system which automatically detects threats that occur in each collision and alerts the rider via visual and audio cues. Moreover, the next system will be focusing on safeguarding the rider's body by inflating an airbag which will be connected to the rider's jacket. An automatic alert system is also introduced where the main objective is to mitigate the consequences of accidents by sending a message to the registered mobile using wireless communication techniques and checks whether an accident has occurred using vibration frequency limits. Location will be sent through the tracking system to cover the geographical coordinates over the area. The proposed domain successfully contributes to a drastic reduction in road accidents. The ultimate objective is to create a better future for everybody through road safety. The survey conducted to test the user satisfactory level, demonstrated high user satisfaction.

Vehicle safety is an enabler of Automated Driving. The combination of active and passive vehicle safety can further increase the safety level of vehicle occupants. With integrated safety systems predicting inevitable crashes and the corresponding crash constellation, the activation of irreversible restraint systems like airbags will allow better crash mitigation and new interior concepts. One requirement is a comprehensive methodology to ensure the correct detection of the current traffic situation, the involved vehicles, and the collision inevitability. This paper presents a novel approach for crash evaluation in the pre-crash phase based on sensor fusion using camera and LiDAR for bullet vehicle detection in combination with physical motion-model-based collision detection. Urban intersection scenarios with typically severe side crashes are investigated using this methodology. The presented method can also be applied to investigate other traffic scenarios. One focus of this paper is the effect of sensor tolerances, which lead to inaccurate object data on the prediction of the inevitability of the crash. The analysis proves the potential of preemptive activation of airbag systems.

An airbag is a crucial passive safety system that protects an occupant in the event of severe vehicle collisions. Its restraint effect can be controlled only when the occupant’s contact data with the airbag is available. A new capacitive tactile sensor is developed and installed on the airbag surface to provide the occupant’s first contact time, contact area and position on the airbag. Based on this feedback, the airbag pressure can be controlled. An airbag deployment is associated with different phases from trigger to full deployment. Before detecting the occupant, it is important to know the effect of these phases on the sensor. In this paper, the phase effects of dynamic airbag deployment on the contact sensor during the simplified static deployment tests are analyzed and discussed. Time-to-first-gas, unfolding of the textile, inflation, and cable capacitance effects are the key points brought to discussion. The results reveal, no effects of time-to-first-gas and inflation on the contact sensor. While the unfolding and cable capacitance have significant effects on the sensor which should be accounted for the occupant detection algorithm.

Airbag is technology in the automotive sector which was created to save the passenger from fatal risks in vehicle accident. Airbag are placed at the point of risk of passenger collision so that the impact load generated from this impact will be muted by airbags of the passenger. This research is designed to be able to perform rescue function not only for passenger, but also for vehicle itself. Because the placement of the airbags was placed on the bumper of vehicle, this part is installed with a high sensitivity sensor to be able to provide information to the system. So the airbags can expand before a impact occurs and the vehicle and its contents will be protected. ECU will send a signal to the squib inflator or also known as an igniter which is an electrical device in the form of a thin bridge cable, igniter will generate heat to burn propylene airbags which will produce nitrogen gas.

Pre-impact fall detection can detect a fall before a body segment hits the ground. When it is integrated with a protective system, it can directly prevent an injury due to hitting the ground. An impact acceleration peak magnitude is one of key measurement factors that can affect the severity of an injury. It can be used as a design parameter for wearable protective devices to prevent injuries. In our study, a novel method is proposed to predict an impact acceleration magnitude after loss of balance using a single inertial measurement unit (IMU) sensor and a sequential-based deep learning model. Twenty-four healthy participants participated in this study for fall experiments. Each participant worn a single IMU sensor on the waist to collect tri-axial accelerometer and angular velocity data. A deep learning method, bi-directional long short-term memory (LSTM) regression, is applied to predict a fall&rsquo, s impact acceleration magnitude prior to fall impact (a fall in five directions). To improve prediction performance, a data augmentation technique with increment of dataset is applied. Our proposed model showed a mean absolute percentage error (MAPE) of 6.69 &plusmn, 0.33% with r value of 0.93 when all three different types of data augmentation techniques are applied. Additionally, there was a significant reduction of MAPE by 45.2% when the number of training datasets was increased by 4-fold. These results show that impact acceleration magnitude can be used as an activation parameter for fall prevention such as in a wearable airbag system by optimizing deployment process to minimize fall injury in real time.

To reduce the size inconvenience of airbag systems employed in human-body protection devices while maintaining comparable gas generation performance, a new family of gas-generating energetic compos- ites are proposed mixing Al/CuO nanothermite with copper complex (Cu(NH3 )4 (NO3 )2 ) known for its propensity to generate gases (0.03 mol/g) such as N2 , O2 , N2 O through exothermic chemical decomposi- tion (300 J/g). The aluminum (Al)/Copper oxide (CuO) couple, known as the most widely studied nanoma- terial for thermite reactions, releasing a high energy, mostly heat, through chemical reaction, is employed as a source of heat to trigger and sustain the decomposition of Cu(NH3 )4 (NO3 )2 complex. This work per- mits developing a new family of gas-generating energetic composites that takes advantage of specific chemical and thermal properties of both materials. We demonstrate its capability to tune the pressuriza- tion rate, burn rate and pressure peak by varying the Al/CuO over Cu(NH3 )(NO2 )2 mass ratio. The peak pressure of Cu(NH3 )4 (NO3 )2 /Al/CuO energetic composites reaches 12 MPa/g.cm3 in a close volume, which is 3.3 higher than that of traditional Al/CuO nanothermite. They achieve much longer high-pressure dura- tion ( ∼30 ms). They also exhibit very intense burning with velocity reaching hundreds of m/s in opening burning experiments. These new materials appear very promising for green gas generation.

Purpose: To report a case of a temporary corneal ectasia induced by airbag trauma. Observations: A patient who suffered a road traffic accident with deployment of the frontal airbag and presented a corneal ectasia in both eyes after 3 months, without changes in visual acuity. After 9 months, he presented a significantly improvement, achieving his basal parameters in pentacam. Conclusions and importance: This is a rare case of corneal ectasia induced by airbag trauma that spontaneously reverted and it can emphasize the viscoelastic properties of the human cornea. info:eu-repo/semantics/publishedVersion

Occupancy detection is a difficult problem. There are several mechanisms exists for occupancy detection in vehicles, particularly in Automobiles. Now, safety has become an important and necessary aspect of the automobile industry. Airbag became a basic and important safety measure in cars. Even though airbag is a vehicle safety device, it can kill children below 12 years due to its rapid action by the exerting lot of force. This project explains about detecting the number of passengers sitting in the car and then classifying each person whether he/she is a child or an adult by processing the image taken from the camera. So that the deployment of airbags can be avoided near children. Each time car speeds from 0 Kmph to 20 Kmph, occupancy of the car is determined and each one is classified again. We are using widely used technique Haar Cascades, for detection. First, we detect faces and then classify each occupant adult or child.

Avalanche airbag backpacks have been shown to be effective at reducing avalanche mortality. However, they are yet to be considered standard avalanche safety equipment, which has long consisted of a transceiver, a shovel, and a probe. This is despite data showing that airbags reduce mortality by decreasing the likelihood of burial. In addition, airbags probably lessen trauma and possibly delay asphyxia. Moreover, the literature suggests airbags reduce mortality at a rate similar to transceivers. For those who work, volunteer, and recreate in avalanche terrain, airbags should be considered standard safety equipment. However, multiple barriers exist for universal adoption, including cost, size, weight, training burden, availability, risk tolerance, and lack of community support and recommendations from professional societies and associations.

Several studies, available in the literature, were conducted to establish the most relevant criterion for predicting the thoracic injury risk on the THOR dummy. The criteria, such as the maximum deflection or a combination of parameters including the difference between the chest right and left deflections, were all developed based on given samples of Post Mortem Human Subject (PMHS). However, they were not validated against independent data and they are not always consistent with the observations from field data analysis. For this reason, 8 additional PMHS and matching THOR tests were carried out to assess the ability of the criteria to predict risks. Accident investigations showed that a reduction of the belt loads reduces the risk of rib fractures. Two configurations with different levels of force limitation were therefore chosen. A configuration representing an average European vehicle was chosen as a reference. It consists of a 3-point belt with a 3.5 kN and then 2 kN digressive limiter, combined with a 54-liter airbag. For better reproducibility and durability, the tests were performed with a pre-inflated bag and a semi-rigid seat. In this first configuration, the THOR dummy had a maximum resulting deflection of 43 mm. To differentiate the criteria, the second configuration was chosen such that it resulted in about the same deflection on the THOR dummy, but with a 5 kN belt force limitation combined with a lower pressure airbag. To reach this target of 43 mm, the pulse severity was lowered. Some criteria were higher in this second configuration, which allows them to be distinguished from the maximum deflection criterion. Four tests on four PMHS were performed in each configuration. The injury assessments showed that the total number of fractures was almost the same in both configurations, but that the number of separated fractures was greater in the 5 kN configuration. 25% of the subjects sustained AIS >3 injuries related to the number of displaced fractures in the 3.5/2 kN load limitation configuration. The result increased to 75% in the 5kN configuration. In total, 8 PMHS and the matching THOR tests were performed and used to assess the ability of the thoracic criteria to predict rib fractures in 2 types of chest loading configurations. The test results did not allow to conclude on the relevance of the criteria measured on the THOR dummy for the total number of rib fractures identified at autopsy (NFR). However, clearly different assessments for separated rib fractures (NSFR), make it possible to differentiate the criteria. The maximum resultant deflection failed to properly predict separated rib fractures while other criteria that include the left-to-right rib deflection difference did.

The aim of this study is to use numerical simulations for safety assessment of an innovative active head restraint system.This system was developed to protect the head and neck of an occupant in a car without a head airbag during a side impact. Its FE model is created and embedded it in a model of a small car with a side airbag. The dynamics of the head restraint activation are also taken into account. The virtual human body model Virthuman is used to represent occupants. The model is scaled for pre-selected human individuals to cover large numbers of occupants of different sizes. It extends conventional virtual valuation of new safety designs via existing pre-defined mono-purpose side dummies and their FE models. The benefit of the head restraint system is evaluated in side impact scenarios inspired by the pole tests performed by EuroNCAP. Transversal impacts to a pole at 29 and 32 km/h are considered at 90° and 75° angles from driver and the opposite side. Also, the far side impact prescribed with an acceleration pulse according to EuroNCAP is considered. Various initial driver sizes in standard seated positions are tested. To extend the study beyond standard testing protocols, out-of-position of driver is also considered, leading to more than 100 simulations of impact scenarios in total. The effect of the innovative head restraint system is assessed from the point of view of driver injury risk.

By studying the working principle of constant current source circuit for airbag ignition test, a pulse constant current source with negative feedback of base current and voltage is designed. The key parameters in the analysis period include: the influence of the voltage swing rate of the operational amplifier, the parasitic capacitance of the MOS tube and the on-off resistance on the establishment time of the output current of the pulse constant current source. The experiment shows that the selection of appropriate devices can meet the requirements of airbag ignition test, the output characteristics of constant current source circuit can meet the requirements of 0-10A adjustable, the frequency 0-5khz adjustable, and the establishment time is less than 50 µ s

The development and evaluation of security solutions for autonomous vehicles is a challenging task. Many researchers have no access to real vehicles to implement and test their solutions. In addition, vehicle E/E architectures of different brands or even model series of one car manufacturer differ significantly. Also, vehicles may be the source of physical hazards, e.g., an exploding airbag. To enable researchers to develop, implement, and evaluate new security solutions for autonomous vehicles, we propose a new security evaluation platform called SEPAD and a dedicated development process for testing security mechanisms with it. SEPAD allows to model realistic E/E architectures where the developed security solutions can be integrated and evaluated without causing safety risks for the researcher or other road users.

This paper presents a new methodological model termed Airbag Moderation: That the relationship between two variables varies as a function of a third, and that this third variable depends upon one of the others. Airbag Moderation extends and bridges a number of theories and it can be implemented using existing statistical models and software packages. Airbag Moderation is more suitable than Moderation for conceptualizing and testing a range of theories, interventions, and policies across educational, social, and behavioural research. An empirical example demonstrates the effectiveness of UK Sure Start Children’s Centres as an intervention in the context of financial disadvantage and the internalizing behaviours of preschoolers. Parallel statistical implementation follows via two Structural Equation Models featuring either a statistical interaction term or a random coefficient. Both indicate that greater use of a Children’s Centre is a significant Airbag Moderator of the relationship between financial disadvantage and internalizing behaviours in preschoolers.

PURPOSE Each year, many cars (in Poland approximately three hundred) are adopted for disabled driver, to enable them to drive the car independently. The purpose of the paper is to assess the key factors which significantly influence the disabled driver behavior during a frontal crash and have the biggest impact on the safety factors. METHODS To achieve the purpose of the paper, the finite element method was used. The authors built the numerical model which includes operation of all safety systems operating in the real car (sensors, seat belts, airbag). Using this method, the authors simulated few different cases of the frontal crash of the car driven by a person with disabilities. RESULTS The obtained results were: displacements, velocities and accelerations of the head, pelvis and shoulders. Additional results were also loads in the neck. Based on the achieved results, several biomechanical parameters and criterions (HIC, Nij) were computed. CONCLUSIONS Therefore, during car adaptation for disabled drivers using a four-point seat belts system, this parameter can be optimized to reduce forces acting on the driver chest. Higher values of the force limit reduce Nij and increase HIC and contact forces between the dummy and seatbelts. Therefore, during designing of the pyrotechnic four-point seat belts system, the pretensioner characteristics should be analyzed taking all the driver's biomechanical parameters into account.

Research on the Event Data Recorder (EDR) and Crash Data Retrieval (CDR) at the University of Malta was extended to also cover a deployment event, i.e. a crash of enough severity that an airbag deployment is commanded. The experimental campaign was based on emulation of vehicle and engine parameters (wheel speeds, vehicle speeds, engine speed) such that experiments were performed in the laboratory while the Electronic Control Units (ECUs) sensed the vehicle as if being driven under various conditions. Over hundred non- deployment events were performed on a single Airbag Control Module (ACM). However the deployment event freezes the ACM, i.e. the ACM cannot be reused. Data of the only one deployment event performed was captured by the EDR, LabViewand a CAN bus sniffer simultaneously. Synchronization of these three different data acquisition platforms was thus required and is discussed in this publication. The synchronization of EDR to CAN bus data was implemented by using an Inertial Measuring Unit transmitting onto the CAN bus. Synchronization of LabViewanalog input data was synchronized by means of a circuit that silenced a purposely injected CAN message.

Software for the simulation of airbags has been available for more than three decades and today is widely used in the automotive industry. Nonetheless, since the introduction of the first wearable airbags for motorcycle riders in the late 1990s, these numerical tools have seen only little application in this fairly new field. The objective of this research is to assess the performance of wearable airbag systems for motorcyclists through experimental tests and numerical simulation. Virtual models are created for two typical test set-ups and numerical results are compared against the corresponding experimental findings. The first test considered is the drop test, derived from the set-up used in EN 1621 for the certification of protectors and employed here to calibrate the finite element airbag model. The second test scenario is the thorax impact test, described in 49 CFR 572 (high-speed test) and SAE J2779 (low-speed test). This set-up, in which the airbag is fitted to a Hybrid III 50th dummy, is used to assess the airbag’s performance in terms of reduction of peak chest deflection and to carry out a parametric analysis on the main airbag parameters: inflation pressure and inflated thickness.

В статье рассматривается возможность использования искусственного интеллекта для повышения безопасности мотоциклистов и водителей средств индивидуальной мобильности (мопедов, электросамокатов, гироскутеров, сигвеев, планетоходов и т.п.), попадающих в аварии. Все эти транспортные средства объединены в статье под одним общим названием малые транспортные средства (МТС), так как они обладают следующими общими признаками: у них отсутствует салон и на этих транспортных средствах находится, как правило, один человек. В статье представлены общие проблемы обеспечения безопасности человека в момент аварии и рассматриваются возможные способы повышения безопасности. Искусственный интеллект может найти здесь применение при прогнозировании момента возможной аварии, при определении порядка работы системы аварийного спасения и при активации этой системы. Рассмотрена схема автоматического принятия решения об аварийном спасении водителя в системе «МТС + человек + окружающая среда» и приведено общее описание элементов, образующих эту систему. Рассматриваемая проблема требует ряда инновационных решений аппаратного, программного и математического характера, она относится к задачам с неопределёнными начальными условиями, её решение в реальном режиме времени требует значительных вычислительных ресурсов. Предложен один из способов сокращения времени поиска аварийных случаев при движении транспортных средств.

Technology is increasing exponentially day by day, besides this increasing of traffic takes place which leads to increasing of accidents. During accidents if airbags are not there then people may die because of severity of accidents. If airbags are present then people can be safe comparatively. To deploy airbags properly we need a system. If airbags can’t deploy properly then people get injured or in some cases they may die. If airbags deploys with high speed then old people and infants may die because of that force of deploying airbags. Beside this if airbags can’t deploy in time then people may die. To control the deployment of airbags we are having different sensors life g sensor, crash sensor, accelerometer sensor. Using any of these sensors it can send alert message to airbag system and we can share our location to our friends or family members and we can send message to ambulance because this is help to save lives of victims. It share’s accident taken place location with the help of GSM sim 300 module by knowing the latitude and longitude of location with GPS NEO 6m module. Here GSM module used to send message and GPS module used to detect the location of accident taken place area. To interface all these we require a micro controller, we used Arduino UNO R3 to interface GPS module, GSM module and crash sensor. For future development we can interface camera to capture the accident area and capture the position of victims in car.

Construction workspace is identified as aggressive work environments. The number of fatalities from falls is growing continuously due to dynamic heavy objects, dangers approaching from multiple directions, trip hazards, challenging surroundings, blind spots, and irregular walk surfaces, which pose severe risks to workers’ safety. Although safety training and organizational monitoring systems are required and are worked as layered protection to the workers, these are often insufficiently effective and lack of body protection systems. This study introduced a prototype of a wearable safety jacket using airbag system developed by advanced weaving technology and optimal sensor and inflator manufacturing technology. The jacket was designed to protect the human body from fall from less than the heights of 5 m without sacrificing productivity and user convenience. The fall shock absorption can be achieved by the advanced inflator system using precision sensors, and by the novel airbag design to minimize air leakage and to manufacture high durability air bag fabric against external impact. The free fall tests were conducted to evaluate the feasibility of the airbag-based wearable safety jacket and assessed the expandability and shock absorption performance among three prototypes. The test results suggested optimum airbag volume and minimum airbag expansion trigger timing to minimize impact and protect human body from falls.

The following chapter proposes a methodology according to which airbag algorithms can be grouped in a three-dimensional model according to their input and output variables, their processing stages and their temporal behaviour.

A 25-year-old male was driving in SUV on Yamuna Expressway without seatbelt. He collided against a concrete divider at a speed of 90 km/h. There was no airbag in car and windshield was shattered. His initial GCS was 12 but on arrival to casualty after 1-h transfer, GCS score was 7.

Workers in different industrial sectors, mainly in the construction and energy areas, face the daily risky situation of falling from the height accidentally, even wearing safety harnesses. To actively protect workers, a safety jacket is proposed. The jacket is equipped with an airbag cushion and an inertial measurement unit, located on the back, to sense the body motion hl. An algorithm deploys the airbag automatically for falls from heights greater than 1 m, leaving enough time for the airbag to be fully inflated. The proposed algorithm is tested and validated against experimental data collected during real falls performed by a professional stuntman, and during months of daily routine workers' life. Particular attention is devoted to the calibration of the tuning parameters, with the aim of the best trade-off between false positives' minimization, reactiveness, and robustness.

Bumper system of a vehicle absorbs the kinetic energy of full-frontal and offset collision. The bumper of a vehicle is the most prominent component considering the safety of the occupant. Design of new bumper system should be done in a way in which the deceleration of the occupant and intrusion in the passenger compartment must reduce. A new way to improve safety in the frontal collision is the implementation of the hydraulic damper in the bumper system of the vehicle. Magnetorheological (MR) fluid damper is suitable for absorbing high-speed impact energy. Implementation of MR damper in the bumper system will reduce the occupant injury. A dynamic model of a vehicle has been developed. This model has four degrees of freedom and damping provided by an airbag is also taken into account, thus giving a more accurate prediction of response during the collision. A new configuration of MR damper has also been proposed.

The following chapter describes the state-of-the-art for all components involved in passive safety, such as the occupant cell, the vehicle structure and the various restraint systems. In particular, the electronic components such as the control unit and sensors will be discussed and the functionality of current airbag algorithms will be explained.

With the rapid development of car crash sensing and identification technology, the application of pre-triggering airbag system is becoming an important option to improve vehicle safety. Thus, the present study aims to investigate the injury protection ability of pre-triggering airbag system and optimize its performance in frontal crashes regarding the key physical parameters. A driver restraint system model established and validated by National Crash Analysis Center was employed and validated for studying the injury protection ability of pre-triggering airbag system. Then, the influences of airbag triggering time, airbag volume scaling factor, inflator mass flow, and exhaust orifice size of pre-triggering airbag system on driver’s head and chest injuries were analyzed. Finally, the weighted injury criterion was selected as the evaluation index to optimize the pre-triggering airbag system. The results show the pre-triggering airbag should be designed with a larger airbag volume and inflator mass flow rate and smaller exhaust orifice. The optimized restraint system design presents a reduction of weighted injury criterion values in 100% and 40% overlapped frontal impacts reaching 25.63% and 42.23%, respectively.

We present a case of a fatal motor vehicle collision of a 22-year-old car driver, who died at the scene after losing control of his car, and subsequently collided with a tree by the roadside. The subsequent autopsy revealed penetrating injuries on the neck, severing the larynx, carotid artery, jugular vein and fracturing the cervical vertebrae. Internal examination showed the offending material to be a semi-cylindrical metal fragment, which had lodged within the paravertebral muscle. Examination of the car with the authorities found that the metal fragment originated from a defective airbag booster cannister, which shattered upon deployment.

The passenger airbag (PAB) requires a large volume and fast deployment because of the large distance between the dashboard and the passenger. And various shapes and sizes of the PAB are required depending on the type of vehicle. However, since the PAB modeling process for each design change is complicated and time consuming, the design parameters of the PAB could not be well investigated. In this study, a unique feature-based CAD system has been proposed that easily constructs PAB CAD model and then generates PAB FE model for collision analysis. Main keypoints and widths of PAB that determine the shape and size have been extracted by analyzing the geometric-feature of airbag. The PAB CAD model can be easily constructed by inputting keypoints and widths information. Then, from the constructed PAB CAD model, the PAB FE model is automatically generated. Finally, the generated PAB FE model can be directly employed for collision analysis, thereby reducing the modeling time of the PAB and enabling efficient parametric studies on design.

Current metal recycling techniques for end-of-life vehicles (ELV) are based on mechanical treatments to mainly recover steel, aluminum, copper, and zinc alloys. Such techniques facilitate compliance with the ELV European Directive (2000/53/EC) target of achieving recyclability quotes of up to 85%. However, a vehicle can use more than 60 metals, some of them considered critical by international institutions, which end up downcycled as part of alloys or ultimately in landfills. This paper undertakes an assessment of the downcycling degree of minor metals in conventional vehicles using a SEAT Leon III model as a case study. Downcycling is assessed from a thermodynamic point of view using thermodynamic rarity, an indicator that is used as a weighting factor for the metals used in the car. The thermodynamic rarity of metals is a function of the quality of the minerals from which they stem, considering their relative abundance in Nature and the energy intensity required to extract and process them. The results demonstrated that, even if the quantity of downcycled metals only represents 4.5% of the total metal weight of the vehicle, in rarity terms, this figure increases to approximately 27%. This indicates that an important portion of high-quality metals becomes functionally lost. The most downcycled vehicle subsystems are in order: (1) accessories, (2) electrical and electronic equipment, (3) exhaust system, and (4) engine. Further, the most downcycled parts are: speed sensor, control unit, antenna amplifier, airbag circuit, temperature and rain sensors, front pipe, particle filter, and turbo parts.