Cooperative Collision Warning System Research Articles

A Novel V2V Cooperative Collision Warning System Using UWB/DR for Intelligent Vehicles.

The collision warning system (CWS) plays an essential role in vehicle active safety. However, traditional distance-measuring solutions, e.g., millimeter-wave radars, ultrasonic radars, and lidars, fail to reflect vehicles’ relative attitude and motion trends. In this paper, we proposed a vehicle-to-vehicle (V2V) cooperative collision warning system (CCWS) consisting of an ultra-wideband (UWB) relative positioning/directing module and a dead reckoning (DR) module with wheel-speed sensors. Each vehicle has four UWB modules on the body corners and two wheel-speed sensors on the rear wheels in the presented configuration. An over-constrained localization method is proposed to calculate the relative position and orientation with the UWB data more accurately. Vehicle velocities and yaw rates are measured by wheel-speed sensors. An extended Kalman filter (EKF) is applied based on the relative kinematic model to combine the UWB and DR data. Finally, the time to collision (TTC) is estimated based on the predicted vehicle collision position. Furthermore, through UWB signals, vehicles can simultaneously communicate with each other and share information, e.g., velocity, yaw rate, which brings the potential for enhanced real-time performance. Simulation and experimental results show that the proposed method significantly improves the positioning, directing, and velocity estimating accuracy, and the proposed system can efficiently provide collision warning.

Collision Risk Assessment Service for Connected Vehicles: Leveraging Vehicular State and Motion Uncertainties

The Internet of Things plays an indispensable role in the development of connected vehicles, which will pave the way for road safety applications. In recent years, the concept of a cooperative collision warning system (CCWS) has been introduced and developed to enhance road safety, and it has been seen as a typical Internet-of-Vehicles application. In most CCWSs, it is vital to have a detection mechanism based on trajectory predictions where the uncertainties associated with vehicular state and motion are complex. However, most available approaches in this regard did not consider these uncertainties. Hence, this article proposes a new collision risk assessment (CRA) method where sigma trajectories that include multiple possible trajectories considering multiple aspects of vehicular motion are designed to cope with vehicular uncertainties. Our method is implemented in a novel server-based architecture, which is different from the commonly used vehicle-based controlled CCWSs. The CRA is provided as a service by a cloud server. The proposed method and architecture are validated and evaluated through extensive real-world experiments. Experimental results show that our method outperforms a referenced method in terms of CRA and achieves better robustness in tolerating communication delays and dropouts. Latencies in CRA service were analyzed, and it was found that powerful computing resources provided by cloud servers can significantly decrease computational cost, which will indirectly compensate for communication costs in the future. Based on our high-performance CRA method, the proposed architecture can be regarded as a novel option for CCWS design.

Cooperative collision warning system design at intersections based on trajectory prediction and conflict risk evaluation

Cooperative collision warning system design at intersections based on trajectory prediction and conflict risk evaluation

Cooperative collision warning system design at intersections based on trajectory prediction and conflict risk evaluation

Cooperative collision warning system design at intersections based on trajectory prediction and conflict risk evaluation

Context and Network Aware Communication Strategies for Connected Vehicle Safety Applications

Connected vehicle systems, such as cooperative collision warning (CCW) or avoidance (CCA) systems, rely on vehicle-to-vehicle communication for obtaining real-time situational awareness and detecting possible hazards. The majority of systems that use vehicular networks may benefit from separation of functionalities in communication and application layers. This separation streamlines design of many applications and provides Internet-style flexibility. However, for critical applications, the inherent loss of performance due to independent operation of communication and application layers may result in unacceptable degradation of reliability. We show that by considering the context and network performance in the communication subsystem design (thus weakening layer independence), significant gain in system reliability is possible. Context awareness is achieved by coupling communication behavior to safety system performance; for example using vehicle tracking accuracy to determine the required communication timing. Network awareness is achieved by using feedback from the network to influence the estimated system performance (tracking error), and consequently the communication controller. Safety performance metrics that can be used include hazard detection accuracy, or warning accuracy for CCW, or vehicle tracking accuracy. Simulation results, using data from field tests, show the effectiveness of context and network aware communication.

Performance Improvement of Collision Warning System on Curved Road Based on Intervehicle Communication

The vehicle on-board sensor based Advanced Driver Assistant System possesses limitations on a small road with a small radius of curvature because of the sensor’s inability to operate in nondetectable domains. This study suggests an Improved Cooperative Collision Warning System (ICCWS) that considers the curvature of the road and is based on intervehicle communication. To predict the radius of curvature of the road, the Arc Relative Distance (ARD), the real relative distance to a preceding vehicle on a curved road has been used. The risk of collision with the preceding vehicle is decided by calculating an index of the risk of collision on a curved road using the computed ARD. The effects of ICCWS, proposed through this simulation, have been reviewed, and the improvement in performance in following a preceding vehicle has been analyzed quantitatively via comparative analysis with the conventional forward collision warning system. Accordingly, if the estimating algorithm for curvature developed in this study is applied to a real system, the performance of following a preceding vehicle can be improved without any specific changes to the system.

Cooperative vehicle collision warning system using the vector‐based approach with dedicated short range communication data transmission

There are three challenges that have to be overcome in order to enhance the accuracy of the cooperative collision warning (CCW) system. First, a vehicle does not always keep the same velocity. Second, the curve road condition should be considered. Third, position interruption caused by Global Positioning System positioning delay has to be tackled. In this study, the authors proposed a vector-based CCW system named VCCW to deal with these three challenges. The simulation results show that the proposed VCCW system has high accuracy's warning rates in both intersection and curve situations. The authors have also implemented the VCCW and tested the system on real roads. Through the VCCW system experiment on real roads, it shows that the VCCW system can alert drivers before collision.

Analytic and Heuristic Methods of Collision Detection for Curve-Moving Vehicle Based on Cooperative Collision Warning System

Analytic and Heuristic Methods of Collision Detection for Curve-Moving Vehicle Based on Cooperative Collision Warning System

Error Analysis and Performance Evaluation of a Future-Trajectory-Based Cooperative Collision Warning System

This paper focuses on the robustness and reliability of a future-trajectory-based cooperative collision warning system (CCWS), which estimates and communicates vehicle positions and predicts and processes future trajectories for collision decision making. The feasibility of the system design has been demonstrated in previous work, and this paper analyzes the error propagation and its impact on detection performance. The reliability of the CCWS heavily depends on the reliability of the differential Global Positioning System (DGPS)-based positioning system and the reliability of intervehicle communication. This paper uses the Kalman filter technique to statistically characterize the errors in position estimation and trajectory prediction, incorporates communication errors as part of the prediction error, and accordingly determines the probability of conflicts and the quality of the detection performance. Results with experimental data are presented to illustrate the error propagation and to demonstrate the reliability of the system.

Cooperative Collision Warning Systems: Concept Definition and Experimental Implementation

The concept of cooperative collision warning (CCW) systems is introduced and explained, followed by presentation of experimental results showing the performance of a first prototype CCW system. The CCW concept provides warnings or situation awareness displays to drivers based on information about the motions of neighboring vehicles obtained by wireless communications from those vehicles, without use of any ranging sensors. This has the advantages of a potentially inexpensive complement of onboard vehicle equipment (compared to ranging sensors that could provide 360-degree coverage), as well as providing information from vehicles that may be occluded from direct line of sight to the approaching vehicle. The CCW concept has been tested on a fleet of five prototype vehicles, supporting a variety of safety services (forward collision warning, blind spot and lane change situation awareness, and several modes of intersection threat assessment). The performance of the vehicle position estimation and wireless communication subsystems are demonstrated using samples of experimental data from test sites with both good and bad Global Positioning System (GPS) signal availability.

DGPS-Based Vehicle-to-Vehicle Cooperative Collision Warning: Engineering Feasibility Viewpoints

The vehicle collision warning system (CWS) is an important research and application subject for vehicle safety. Most of this topic's research focuses on autonomous CWSs, where each vehicle detects potential collisions based entirely on the information measured by itself. Recently, an alternative scenario has arisen. This scenario is known as cooperative driving, where either the vehicle or the infrastructure can communicate its location, intention, or other information to surrounding vehicles or nearby infrastructure. Since installing a low-cost global-positioning-system (GPS) unit is becoming a common practice in vehicle applications, its implications in cooperative driving and vehicle safety deserve closer investigation. Furthermore, the future trajectory prediction may lead to a straightforward approach to detect potential collisions, yet its effectiveness has not been studied. This paper explores the engineering feasibility of a future-trajectory-prediction-based cooperative CWS when vehicles are equipped with a relatively simple differential GPS unit and relatively basic motion sensors. The goals of this paper are twofold: providing an engineering argument of possible functional architectures of such systems and presenting a plausible example of the proposed future-trajectory-based design, which estimates and communicates vehicle positions and predicts and processes future trajectories for collision decision making. In this paper, common GPS problems such as blockage and multipath, as well as common communication problems such as dropout and delays, are assumed. However, specific choices of GPS devices and communication protocol or systems are not the focus of this paper