International Journal of Vehicle Safety (12 papers in press)
Reduction of end-to-end delay using threaded RaptorQ codes in VANETs
by Nandhini Vineeth, H.S. Guru Prasad
Abstract: Multimedia data transmission, a prevalent and significant requirement in Vehicular Adhoc NETworks (VANETs) demands less end-to-end delay. The transmission of data in VANET scenarios is challenging as the vehicles are mostly on the move, resulting in dynamic topology. RaptorQ (RQ) codes help in error correction, where the redundant symbols sent along with the actual symbols help in correcting the errors encountered in the receiver(s), eliminating the requirement of retransmission. In this work, the reduction of end-to-end delay of the video data transmitted in VANETs is achieved with the usage of RQ codes, while encoding in the transmitter and decoding in the receiver. Multithreading is introduced in both ends to further reduce the delay incurred. The various scenarios exhibiting all possible combinations of single or multiple hops, single transmission or multiple transmission are observed, and the results showing the influence of the RQ encoder and decoder in reducing the end-to-end delay are presented.
Keywords: VANET; RaptorQ; QoS; NS3; end-to-end delay; video streaming; multithreading; encoding; decoding; IEEE 802.11p; RQ codes.
Categorisation of driving scenario complexity based on primary driving tasks and road characteristics
by Miguel Angel Galarza, Josep Paradells
Abstract: The increasing amount of infotainment services available in vehicles makes it necessary to devise a system capable of managing how information should be delivered and accessed in accordance with the driving complexity scenario. The objective of this study is to provide a useful model for categorising driving scenarios in terms of their complexity. For this purpose, data collected from driving tests are analysed by employing data mining techniques and machine learning methods for finding the more influential variables of driving complexity. The input variables used are associated with primary driving tasks and road characteristics available in current vehicles. As a result, the most relevant variables that enable the categorisation of the driving scenario are identified, and a model capable of predicting driving complexity in real time is constructed. Given the model accuracy obtained, a practical application could be the adaptation of human-machine interface.
Keywords: driving complexity; primary driving task; data mining; machine learning; vehicle safety; human-machine interface.
Emergency call system definition via robustness structure in vehicle applications
by Ahmet Apak
Abstract: The European Union Parliament introduced the legislation EU-2015/758, which includes the obligation of emergency call system equipped vehicles in the European countries with the starting date of 31 March 2018. After the regulation started to be applied, new system updates and modifications in the vehicle systems are released. Emergency call (eCall) system can be applied to the vehicle structures with different types, such as manual eCall device, automatic eCall device including control unit and/or measurement unit. Whereas a manual eCall device is triggered manually, an automatic eCall device is activated automatically when an accident occurs. In this point of view, the emergency call structure in the vehicle system is defined by its robust working principles, including boundary diagram, P-diagram, and verification methods, which enables the system to work properly.
Keywords: eCall equipped vehicle; emergency call system; eCall; emergency call device; manual eCall device; automatic eCall device; eCall control unit; eCall measurement unit; smart vehicle system; crash notification system.
Finite element analysis of the foam-filled bitubal circular tube under multi-impact loading
by Fauzan Djamaluddin
Abstract: Crush analysis of bitubal cylindrical tubes under different impact angles (0˚, 10˚, 20˚, 30˚) is described in this paper. Finite element analysis (FEA) was used to determine the numerical solutions of double cylindrical tubes. Moreover, a mass block as the impactor impacted the structure in the longitudinal direction of the tubes. With variations of load angle and dimensions of the tubes, a model of the structure was developed using nonlinear ABAQUS sofware. The parameters such as the peak crushing force (PCF), energy absorption (EA) and specific energy absorption (SEA) are the outcomes of this study, showing that this tube is a good energy absorber.
Keywords: circular tube; oblique impact; finite element; crashworthiness; impact.
Effectiveness of vehicle passive safety systems in lateral fixed-object collisions
by Luke Gaylor, Mirko Junge, Sylvester Abanteriba
Abstract: Lateral impacts with narrow objects subject the side of the vehicle to highly concentrated loading, where the occupant's head/face/neck region was previously the most frequently injured. Passive safety systems such as thoracic and head side airbags attempt to prevent injury during the given impact. The aim of the research is to evaluate the real world effectiveness of the airbags systems by reviewing NASS-CDS data. Injury risks are determined for regional specific injuries using the new injury severity score. The risk of injury is directly compared for vehicles with and without the deployed airbags. A series of descriptive statistics also demonstrates the importance of protecting a given body region by evaluating the injuries incurred at other body regions. A total of 209 raw events (60,794 weighted) were obtained, of which 38 (2784 weighted) vehicles provided additional thoracic protection with the airbag and 28 (2450 weighted) which had a head airbag deployed. The results indicated a strong protective ability of the head side airbags to prevent injury. When these units deployed during impact, no occupant incurred an NISS_HFN<16 injury. On the other hand, no distinctive benefit could be attributed to the deployed thoracic airbags. In fact when the vehicle underwent lateral intrusion between 15 and 30 cm, and the risk of NISS_THO<4 injury was greater when the airbag deployed than when it was not available (injury risk with deployment 0.555+-0.279, without 0.088+-0.047). Head side airbags systems have shown a strong protective ability in real world accidents to prevent the previously most prevalent injury, whereas no supplementary protection could be attributed to the thoracic side airbags. The frequency of lateral fixed-object collisions has substantially reduced since they were identified as problematic during the 1980s, therefore as it remains as a means to validate vehicle platforms, it is not a representative example of frequently occurring real-world collisions.
Keywords: fixed object collisions; side airbags; thoracic injury; head/face/neck injury; pelvis injury; abdomen injury.
Robust real-time driver drowsiness detection based on image processing and feature extraction methods
by Maryam Keyvanara, Nasrin Salehi, Amirhassan Monadjemi
Abstract: Recently, the human lifestyle has strongly been affected by the novel technological equipment. The applications of Artificial Intelligence are widely being utilised to improve the performance and quality of the modern life. One of the important applications of these techniques is to seek to improve public safety, including the safety of driving. The statistics indicate that the mortality of car accidents yearly constitutes a significant proportion of the overall deaths. A number of strategies have been studied to materialise driver drowsiness detection systems. One of the best strategies relies on image processing and computer vision methods. In this paper, a novel real-time method for driver drowsiness detection is presented. This method uses Haar wavelet-based features for face detection. The eye state determination has been performed using PCA feature extraction along with an SVM classifier. The proposed method has been implemented and tested on a real-time ARM based embedded system, with a camera installed in front of the driver. Results show that the presented intelligent system has a high detection accuracy, compared to the methods presented thus far, on the standard datasets such as BioID and RS-DMV.
Keywords: driver drowsiness detection; Haar cascade classifier; SVM; face and eye detection; real-time tracking; PCA.
Crashworthiness optimal design of a new extruded octagonal multi-cell tube under dynamic axial impact
by Zhonghao Bai, Kai Sun, Feng Zhu, Libo Cao, Jun Hu, Clifford C. Chou, Binhui Jiang
Abstract: A new extruded octagonal multi-cell tubular energy absorber is developed for improving and enhancing the vehicle crashworthiness. A combined experimental and numerical study is conducted to further assess its performance. In this study, a sled impact test is first performed to investigate the structural response of an octagonal multi-cell tube, and the test data are then used to validate the FE tube model. Using this FE tube model, the effect of key geometric parameters on the structural crashworthiness is analysed in detail. It is found that the number of webs along the circumferential direction, the size of inner tube and wall thicknesses of outer tube, web and inner tube have significant effects on crashworthiness of the energy absorber mentioned above. Based on the parametric study, multi-objective optimisation is subsequently performed to further improve its energy absorption efficiency. These findings can provide valuable guidelines for designing such new types of energy absorber under dynamic axial impact.
Keywords: octagonal multi-cell tube; energy absorption efficiency; energy absorber; sled impact test; structural crashworthiness; multi-objective optimisation; dynamic axial impact.
Understanding the spatial patterns of tanker accidents in Nigeria using geographically weighted regression
by Moses O. Olawole, Olabisi M. Olapoju
Abstract: Road traffic accidents involving tankers are important causes of death and injury in Nigeria. This study examined spatial patterns and possible determinants of tanker accidents in Nigeria. Secondary data on tanker accidents for the year 2007 to 2010 and other relevant data were sourced from the databases of the Federal Road Safety Commissions of Nigeria and National Bureau of Statistics. The spatial patterns of tanker accidents were mapped using Global and local Moran's I statistics. The data were also subjected to Ordinary Least Square and Geographically Weighted Regression techniques. Findings indicated that tanker accidents vary by state and also revealed an upward trend in the occurrence of tanker accidents. The local Moran's I indicate persistent clustering of tanker accidents in two states throughout the study periods. Factors influencing the patterns of tanker accidents in the country were identified. The study recommends strategies for the avoidance of tanker accidents in Nigeria.
Keywords: accidents; spatial; tanker; OLS; GWR; Nigeria.
Can electroencephalography improve road safety? An EEG-based study of driver's perception of traffic light signals in a virtual environment
by Md. Reshad Ul Hoque, Gleb V. Tcheslavski
Abstract: Virtual traffic light environment was simulated by exposing the test subject to images of traffic lights to study his cognitive responses. Electroencephalogram (EEG) was collected from a driver in this environment, pre-processed and decomposed into EEG rhythms with wavelet transform. Epochs related to individual visual stimuli were extracted. Minimum and maximum values, standard deviation, skewness, kurtosis, and variance were used as feature vectors for classification with K-nearest neighbour (KNN) and neural network classifiers to discriminate between different traffic light colours. Classification accuracy was 84.05% and 86.94% for KNN and NN classifiers respectively, while the highest performance was observed for images of yellow lights. We conclude that drivers may perceive different traffic lights differently and that their perception results in distinct neurological activities reflected in EEG. Therefore, EEG-based detection of traffic lights may be possible that may be implemented in future automotive BCI systems expanding cars' assistive driving capabilities.
Keywords: road safety; traffic lights; electroencephalogram; wavelet transform.
Design and analysis of an impact energy absorbing steering system
by M.S. Patil, Varun Galgali
Abstract: In a country that continues to hold the record for high road deaths every year, it is important to have reliable safety system in vehicles which is an absolutely crucial pre-requisite for driver safety. The latest tests, conducted by Global NCAP (New Car Assessment Program), showed that in an accident, most budget cars would leave the driver with possible life-threatening injuries. For such cars with insufficient or unreliable safety devices, this paper deals with the design of an impact absorbing steering column, used to achieve controlled deceleration of a restrained/unrestrained occupant to reduce the impact forces and thus reducing the chances of fatal injuries.
Keywords: impact absorbing systems; steering systems; driver safety.
Special Issue on: Vehicle Active Safety for Intelligent Transportation Systems
Fuzzy fractional PID gain controller for antilock braking system using an electronic wedge brake mechanism
by Fauzi Ahmad, Saiful Amri Mazlan, Khisbullah Hudha, Hairi Zamzuri, Hishammudin Jamaluddin
Abstract: This paper focuses on the design of a adaptive fuzzy Proportional-Integral-Derivative (PID) with fractional gain controller. The controller, which is based on the conventional PID controller, is modified to be P1-α I1-β D1-γ; with the objective to make the controller more flexible and elastic to the changes in input and the system parameter. In this control structure, the fuzzy logic controller acts as the tuner for the parameter of α, β and γ, so that the overall controller parameter can be varied to adapt to the changes in a system. The designed controller is applied to a validated antilock braking system model. Numerous numerical simulations and comparisons with other PID with fractional gain and conventional PID controllers show that the fuzzy fractional PID controller not only ensures good control performance with respect to reference input but also improves the system effectiveness with respect to model uncertainties.
Keywords: fuzzy logic controller, fractional PID controller, fuzzy fractional PID controller, antilock braking system, electronic wedge brake
A preliminary study to optimise safety conditions on a freight urban robotic vehicle
by Giovanni Gerardo Muscolo, Giorgio Moregola, Rezia Molfino
Abstract: The paper presents a new concept architecture of light duty fully electric vehicle for efficient sustainable urban freight transport which allows the movement of two Euro Pallets 800 × 1200 mm (or boxes with similar bottom part). Active suspensions of the vehicle have been designed in order to adapt their stiffness to the payload on board and to modify the chassis height during loading-unloading tasks. In this paper, a preliminary study to optimise safety conditions on goods on board of the vehicle, and on people near the vehicle is presented. In order to guarantee safety conditions for the vehicle's driver and city areas where the vehicle should be moved, design optimisations on the chassis have been developed. These optimisations have been compared using computational analysis. Two alternative solutions have been proposed and one of the presented results has been included on the real vehicle.
Keywords: safety; freight transport; robotic vehicle; computational analysis.