Changes of drivers’ visual performances when approaching a signalized intersection under different collision avoidance warning conditions

Differences in fatal loss-of-control accidents between young male and female drivers

Factors affecting teen drivers' crash-related length of stay in the hospital

Vibrotactile collision warning signals that create a sensation of motion across a driver's body result in faster brake reaction times (BRTs) to potential collision events. To date, however, such warnings have only simulated linear motion. We extended this research by exploring the effectiveness of collision warnings that incorporate vibrotactile patterns or "vibrotactile flow". In Experiment 1, expanding and contracting vibrotactile flow warnings were compared with a static warning (all tactors activated simultaneously) and a no warning condition in a car following scenario. Both vibrotactile flow warnings produced significantly faster BRTs than the static and no warning conditions. However, there was no directional effect. That is, there was no significant difference between contracting and expanding signals. Warnings that utilize vibrotactile flow therefore appear to provide an effective means of informing drivers about potential collision events. However, unlike comparable warnings utilizing linear motion, their effectiveness does not seem to depend on the precise relationship between the warning and collision events. Experiment 2 demonstrated that a tactile warning incorporating linear motion produced significantly faster BRTs than an expanding vibrotactile flow warning. Taken together, these results suggest that vibrotactile warnings that simulate linear motion may be more effective than vibrotactile flow warnings.

The objective of the study was to assess the independent contribution of individual, car and circumstantial features in severe and fatal car crashes involving young drivers. A prospective longitudinal, register-based cohort study was conducted at national level (in Sweden), in which people born in the years 1970 – 1972 (n = 334 070) were followed up for the period 1988 – 2000 (aged 16 – 18 years in 1988) for their first two-car crashes leading to severe or fatal injury. Ten variables descriptive of the driver (socio-demographics), the car (safety level) and the crash have been analysed using multiple logistic regressions for male and female drivers separately, compiling crude and adjusted odds ratios with 95% CI. When controlling for other features, none of the variables descriptive of male and female drivers' socio-demographic characteristics impacts significantly on the odds of being severely injured or dying in a car-to-car crash. After adjustment, significant excess risks are observed for speed limits higher than the lowest one, type of crash other than rear end collision and road and light conditions other than favourable (dry and daylight), for both male and female drivers. For males only, cars from all car safety levels have significantly higher odds than those from the safest category. Among male and female young drivers, class differences in the risk of being severely injured in a traffic injury are substantial. Yet, despite this imbalance, crash characteristics (for males and females) and safety level of the vehicle driven (for males) remain the most determinant factors of crash severity. Understanding the social patterning of road traffic injuries is a challenge for public health and it seems that qualitative and quantitative differences in crash exposure offer part of the explanation. Young drivers from all social groups need, however, to be sensitized to the risk factors.

During the process of collision avoidance, especially in a multi-ship encounter situation, the dynamic interactions among individual ships impose a significant impact on collision avoidance decision-making. It is imperative, therefore, that collision avoidance decisions are formulated with a comprehensive consideration of not only the current direct collision conflict but also the potential conflicts due to planned collision avoidance actions. To address this requirement, this paper proposes a dynamic conflict cluster detection method for collision avoidance decision-making in multi-ship encounters. The involved ships are clustered into stable temporal-dependent ship conflict groups taking into account both conflict connectivity and the potential spatiotemporal interactions originating from planned collision avoidance actions. The conflict cluster detection model is implemented within a framework to achieve hierarchical coordinated collision avoidance decision-making. By a simulation experiment of an 11-ship encounter, the proposed method successfully discerns the ships with conflicts and provides feasible collision avoidance decisions. Compared to the non-cluster collision avoidance methods, the proposed method generates the results with acceptable deviating distance and number of collision avoidance actions at minimum computation load. It has been demonstrated that the proposed method is both effective and efficient for officers on board and operators at Vessel Traffic Services centers in real-life navigation.

In order to increase traffic safety on our roads, certain forms of behavior and personality traits of passenger car drivers were studied. As an attempt to understand the potential contribution of drivers’ impulsiveness and aggressiveness in traffic accidents in Sulaimaniyah City, this study was conducted. The correlation between drivers’ impulsiveness and aggressiveness were also explored. Participants, who filled Barratt Impulsiveness Scale (BIS-11) and Aggressive Driving Behavior Questionnaire (ADBQ), were 244 drivers. The male drivers who answered the questionnaires were 143, while female drivers were 101. The results of the statistical analyses showed that male drivers are driving more aggressively than female drivers; as a result, male drivers faced higher numbers of traffic accidents than female drivers. There were no significant differences between male and female drivers regarding drivers’ impulsivity. Speeding as a measuring scale of the aggressive driving is significantly correlated with second-order impulsiveness subscales. The attentional and motor impulsiveness subscales are more correlated with the total score of the driving aggressiveness than non-planning subscale. There was moderate correlation between the impulsiveness total score and the overall aggressiveness score. The impulsiveness of the drivers was negatively correlated with the drivers’ ages and positively correlated with number of crashes; while the driving aggressiveness was significantly correlated with number of crashes and negatively with gender and age of the drivers. The traffic police in Sulaimaniyah City can benefit from the results of this paper during permitting driving license and enforcement processes.

Operations in the Next Generation Air Transportation System (NextGen) are planned to have a reduced dependency on primary surveillance radar and use Automatic Dependent Surveillance - Broadcast (ADS-B) to provide aircraft state information to Air Traffic Control (ATC) and onboard collision detection and avoidance systems. With the ongoing integration of Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS), ADS-B is expected to become the main surveillance input to UAS collision avoidance. Traffic Alert and Collision Avoidance System (TCAS) is unable to meet requirements in terms of adaptability to future operations with reduced separation margins, addition of new user groups (e.g., UAS), and support of additional surveillance inputs. Airborne Collision Avoidance System (ACAS X) is being designed to meet these requirements and to increase surveillance, alerting, and resolution performance. The RTCA has released Minimum Operational Performance Standards (MOPS) to provide system and operational performance characteristics that ADS-B must provide. This paper analyzes recorded ADS-B data from test flights that were performed in the Continental U.S. (CONUS) and verifies measured performance with specified operational characteristics in terms of coverage, accuracy, and integrity.

Association between the presence of passengers and at-fault crash risk among older drivers with and without cognitive decline.

Effect of warning message on driver’s stop/go decision and red-light-running behaviors under fog condition

ABSTRACTThis paper proposes a new safety system named emergency steering assist (ESA), which consists of the autonomous steering subsystem and differential braking subsystem. The control system is developed to mediate the conflict objectives of vehicle stabilisation and rear-end collision avoidance in highway driving. Instead of predefining a collision-free trajectory in the entire process of collision avoidance, the process of collision avoidance is divided into two stages. In stage 1, where the vehicle is guided to enter the adjacent lane with a constant centripetal acceleration to avoid collision, the steering manoeuvre is determined by the feedforward controller based on the steering dynamics. In stage 2, where the vehicle is guided along the centreline of the adjacent lane, the steering manoeuvre is determined by the controller based on the theory of model predictive control. In addition, the differential braking subsystem is designed with a comprehensive treatment to the requirements of collision avoidance and vehicle stabilisation. Finally, the simulation results demonstrate that the proposed ESA system can effectively achieve better balance between an emergency collision avoidance manoeuvre and vehicle stabilisation at high speeds in different conditions. The hardware-in-the-loop experiment developed by the authors is used to validate the real-time performance and effectiveness of the proposed control scheme.

In this paper, five participants take part in the driving simulator experiment. The simulated urban road is not interrupted, and the drivers’ electroencephalogram (EEG) data, driving simulator data, and experimental video data are recorded synchronously. We put vehicles that change lanes randomly in the experimental scene to simulate the real situation, thus to get the changes in brain activity and the driving behavior. The power spectrum density and the energy of each frequency band of EEG signal are extracted by using the fast Fourier transform (FFT). The result indicates that (1) the beta wave has obvious advantages, when the driver faces a suddenly lane change in the front vehicle during continuous driving; the driver focuses on the front vehicle, and responds quickly to the events. (2) the female drivers are generally more stable than male drivers, but the response to environmental change is slower than that of the male drivers. (3) the drivers’ first reaction when facing the suddenly lane change is to press the brake pedal and then steer off.

In this paper, we present a scooter collision avoidance system that can identify red-light runners (RLRs) at intersections. When the RLR behavior is detected, the system would advise the RLR to slow down immediately and warn nearby vehicles on the intersecting road in real time. In particular, we do not consider infrastructure-based solutions such as those utilizing a radar or a camera. This is because, in addition to high implementation costs, collisions can be only avoided at intersections where such infrastructure configurations are deployed. Instead, we advance an on-scooter solution using smartphones carried by scooter riders. Smartphones provide a useful platform that has a high penetration rate, more than sufficient computational power, inertial sensors to reflect the driving behavior, and the communication capability to transmit or receive information from other vehicles. In our system, we utilize a support vector machine and design an RLR classifier for learning and predicting RLR behaviors. The evaluation results show that our system is able to achieve over 70% recognition rates when distinguishing between RLR and non-RLR cases, as compared with approximately 80% recognition rates of the infrastructure-based (and higher cost) solution using a laser range finder (LADAR).

Time/frequency technology provides a reliable aircraft collision avoidance system (CAS) that can operate in either synchronous or asynchronous modes. Precision time-ordered techniques of CAS provide both range and range-rate measurements in a one-way sense to all aircraft as well as ground stations within range of transmitted microwave signals. The cooperative system utilizes exact frequency references coupled with precise synchronization: control of frequency to 1 part in 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> and time to less than 1 µs. In addition to performing specific functions of protecting aircraft, the time/frequency CAS provides a means for wide dissemination of submicrosecond timing. Flying clocks, which are an integral part of the airborne CAS, have been providing transcontinental and intercontinental transfer of time since 1964. CAS ground stations can serve as depositories of time and frequency derived from flying clocks, satellites, Loran-C and Omega navigation systems, or television transfer referenced to national and international time/frequency standards. Airborne relay of CAS time provides a ready means for local transfer of time to users that are not within line of sight to a ground station. Thus time and frequency can be disseminated for applications other than collision avoidance. In the process of developing the technology and originating CAS, new systems for communication, position determination, navigation, and vehicle surveillance evolved. Such systems can be structured to operate at high data rates, provide improved accuracy and use less RF spectrum than existing techniques.

Although the navigation safety has been greatly improved nowadays, automation of ship driving are not achieved completely as the automation of collision avoidance has not achieved perfectly. This paper mainly research on ship domain modeling and application for ship collision avoidance. The novel achievements are that it proposed a 3-d model of ship domain and improved the danger judgments of collision to determine the more suitable timing and magnitude of action. This paper divided process of ship collision avoidance into three stages: ship domain build stage, danger judgment stage and action stage. Based on theories of each process of ship collision avoidance codified in 2-d coordinate system, this paper made simulations for crossing situation to express collision avoidance process.

&lt;div class="htmlview paragraph"&gt;Since 1955 the aviation community has been investigating the feasibility of an airborne collision avoidance system. These studies have included analytical and engineering design efforts as well as flight simulation tests and actual flight tests. The majority of the effort expended during these investigations has been devoted to the engineering aspects of the systems. Of equal importance in meeting the overall objective of collision avoidance is the transmission of system information to the crew in a form that can be used effectively in the operational environment. The Boeing Commercial Airplane Company fulfilled a contract for the FAA, using simulation to help determine flight deck display requirements and operational procedures for the traffic alert and collision avoidance system (TCAS II) in commercial transport aircraft.&lt;/div&gt; &lt;div class="htmlview paragraph"&gt;Using the experience gained from these studies, this paper describes the type of efforts required to develop pilot factor characteristics for future collision avoidance systems it addresses man-machine interface requirements to ensure that the system is compatible with the overall aircraft system. It presents some of the functional requirements that the display and control components of the system must meet to accomplish separation assurance. Some of the subjects that are discussed include: a) the impact of the collision avoidance system utilization philosophy on the display requirements; b) the importance of designing the collision avoidance display system so that it can be integrated into the flight deck environment; c) techniques for incorporating realistic human performance estimates into the system performance assumptions; d) the effect on system performance of using natural response patterns; e) techniques that can be used to generate pilot response time commensurate with the situational requirements; f) the role of simulation in the design process; and g) consideration for certification during the development of a collision avoidance system.&lt;/div&gt;