Inter-Vehicle Communication Protocol Research Articles

Inter-Vehicle Communication Protocol Design for a Yielding Decision at an Unsignalized Intersection and Evaluation of the Protocol Using Radio Control Cars Equipped with Raspberry Pi

The Japanese government aims to introduce self-driven vehicles by 2020 to reduce the number of accidents and traffic jams. Various methods have been proposed for traffic control at accident-prone intersections to achieve safe and efficient self-driving. Most of them require roadside units to identify and control vehicles. However, it is difficult to install roadside units at all intersections. This paper proposes an inter-vehicle communication protocol that enables vehicles to transmit their vehicle information and moving direction information to nearby vehicles. Vehicles identify nearby vehicles using images captured by vehicle-mounted cameras. These arrangements make it possible for vehicles to exchange yielding intention at an unsignalized intersection without using a roadside unit. To evaluate the operations of the proposed protocol, we implemented the protocol in Raspberry Pi computers, which were connected to cameras and mounted on radio control cars and conducted experiments. The experiments simulated an unsignalized intersection where both self-driven and human-driven vehicles were present. The vehicle that had sent a yielding request identified the yielding vehicle by recognizing the colour of each radio control car, which was part of the vehicle information, from the image captured by its camera. We measured a series of time needed to complete the yielding sequence and evaluated the validity of yielding decisions.

The Traffic Adaptive Data Dissemination (TrAD) Protocol for both Urban and Highway Scenarios.

The worldwide economic cost of road crashes and injuries is estimated to be US$518 billion per year and the annual congestion cost in France is estimated to be €5.9 billion. Vehicular Ad hoc Networks (VANETs) are one solution to improve transport features such as traffic safety, traffic jam and infotainment on wheels, where a great number of event-driven messages need to be disseminated in a timely way in a region of interest. In comparison with traditional wireless networks, VANETs have to consider the highly dynamic network topology and lossy links due to node mobility. Inter-Vehicle Communication (IVC) protocols are the keystone of VANETs. According to our survey, most of the proposed IVC protocols focus on either highway or urban scenarios, but not on both. Furthermore, too few protocols, considering both scenarios, can achieve high performance. In this paper, an infrastructure-less Traffic Adaptive data Dissemination (TrAD) protocol which takes into account road traffic and network traffic status for both highway and urban scenarios will be presented. TrAD has double broadcast suppression techniques and is designed to adapt efficiently to the irregular road topology. The performance of the TrAD protocol was evaluated quantitatively by means of realistic simulations taking into account different real road maps, traffic routes and vehicular densities. The obtained simulation results show that TrAD is more efficient in terms of packet delivery ratio, number of transmissions and delay in comparison with the performance of three well-known reference protocols. Moreover, TrAD can also tolerate a reasonable degree of GPS drift and still achieve efficient data dissemination.

Platoon based cooperative driving model with consideration of realistic inter-vehicle communication

Recent developments of information and communication technologies (ICT) have enabled vehicles to timely communicate with each other through wireless technologies, which will form future (intelligent) traffic systems (ITS) consisting of so-called connected vehicles. Cooperative driving with the connected vehicles is regarded as a promising driving pattern to significantly improve transportation efficiency and traffic safety. Nevertheless, unreliable vehicular communications also introduce packet loss and transmission delay when vehicular kinetic information or control commands are disseminated among vehicles, which brings more challenges in the system modeling and optimization. Currently, no data has been yet available for the calibration and validation of a model for ITS, and most research has been only conducted for a theoretical point of view. Along this line, this paper focuses on the (theoretical) development of a more general (microscopic) traffic model which enables the cooperative driving behavior via a so-called inter-vehicle communication (IVC). To this end, we design a consensus-based controller for the cooperative driving system (CDS) considering (intelligent) traffic flow that consists of many platoons moving together. More specifically, the IEEE 802.11p, the de facto vehicular networking standard required to support ITS applications, is selected as the IVC protocols of the CDS, in order to investigate how the vehicular communications affect the features of intelligent traffic flow. This study essentially explores the relationship between IVC and cooperative driving, which can be exploited as the reference for the CDS optimization and design.

VANET Coverage Analysis for GPS Augmentation Data in Rural Area

Abstract: Enhanced position accuracy is key for modern navigation systems, location based services and applications based on Inter-Vehicle Communication (IVC). Position data are the foundation for deriving vehicle trajectories used for assessing a situation’s criticality in vehicle safety. Thus, especially Advanced Driver Assistance Systems (ADASs) and integral safety applications benefit from nearby vehicles spreading their positions periodically with high accuracy. Positioning based on Global Navigation Satellite System (GNSS) measurements can be enhanced by established Cooperative Positioning (CP) methods like Real-Time Kinematic (RTK) and Differential GNSS (DGNSS). Conventional CP relies on positioning correction data from a third party, whereas this paper introduces a self-sufficient CP system based on Precise Point Positioning (PPP) and Vehicular Ad-Hoc Network (VANET) technology requiring no infrastructure. Furthermore, the data dissemination process and achievable coverage are analysed by a simulation study for a rural area in Bavaria, Germany. For this purpose, the simulation employs the European IVC protocol stack ITS-G5. While the general feasibility of this CP approach could be assured, some remaining issues regarding employed network protocols were discovered as well.

Toward Realistic Simulation of Intervehicle Communication

The quality of intelligent transportation systems strongly depends on the underlying communication protocols and techniques. In this article, we discuss the current state of the art, trends, and open problems in the area of simulation techniques used to study intervehicle communication (IVC). Here, we touch on a broad range of topics but focus on three aspects that have a strong influence on the degree of realism and hence the reliability of simulation results: the need to integrate microscopic mobility models, the used evaluation metrics, and the impact of human driver behavior on a macroscopic scale. We study and discuss the state of the art of simulation-based performance evaluation of IVC protocols and applications. In the scope of this article, we concentrate on the most recent advances and findings by outlining selected models, techniques, and issues that are specifically related to IVC, with a strong focus on aspects beyond network simulation issues. The main objective is to determine the degree to which available simulation techniques produce realistic results.

Bidirectionally Coupled Network and Road Traffic Simulation for Improved IVC Analysis

Recently, many efforts have been made to develop more efficient Inter-Vehicle Communication (IVC) protocols for on-demand route planning according to observed traffic congestion or incidents, as well as for safety applications. Because practical experiments are often not feasible, simulation of network protocol behavior in Vehicular Ad Hoc Network (VANET) scenarios is strongly demanded for evaluating the applicability of developed network protocols. In this work, we discuss the need for bidirectional coupling of network simulation and road traffic microsimulation for evaluating IVC protocols. As the selection of a mobility model influences the outcome of simulations to a great extent, the use of a representative model is necessary for producing meaningful evaluation results. Based on these observations, we developed the hybrid simulation framework Veins (Vehicles in Network Simulation), composed of the network simulator OMNeT++ and the road traffic simulator SUMO. In a proof-of-concept study, we demonstrate its advantages and the need for bidirectionally coupled simulation based on the evaluation of two protocols for incident warning over VANETs. With our developed methodology, we can advance the state-of-the-art in performance evaluation of IVC and provide means to evaluate developed protocols more accurately.

Evaluation of dissemination-based inter-vehicle ad-hoc communication protocols for local traffic information services

In this paper, we propose inter-vehicle ad-hoc communication protocols called Speed-Dependent Random Protocol (SDRP), Received-Message-Dependent Protocol (RMDP) and RMDP with Error Counting (RMDPwEC), which disseminate and propagate the preceding traffic information to the following vehicles, and discuss its performance. These protocols dynamically change the dissemination interval depending on the vehicles' speed and the number of reception messages, respectively. Our simulation results show that by using RMDPwEC, a lot of vehicles can acquire the preceding traffic information within very short periods. In addition, we have also shown that selection of disseminated data affects preceding traffic information acquiring time. Each vehicle holds other vehicles' tracks for some period. Depending on the number of preserved other vehicles' tracks and their preserved period, propagation ratio of the preceding traffic information varies. Some simulation results are explained.

Improving the Accuracy of IVC Simulation Using Crowd-sourced Geodata

We discuss the use of crowd-sourced geodata in simulative evaluations of Inter-Vehicle Communication (IVC) protocol designs. Typically, network simulation tools, which have been improved over decades of network research, are used for evaluating communication systems. In the area of IVC, however, additional challenges have to be met. Most important, the mobility of vehicles in network simulation needs to be represented accurately, e.g., using road traffic microsimulation techniques. These can be integrated with network simulation tools in order to provide a holistic view on the overall system performance. Obviously, the quality of these approaches inherently depends on the quality of provided map data. The OpenStreetMap project provides a community-maintained repository under an open license model. The available crowd-sourced geodata not only consists of road topology data but also includes fine-grained details such as traffic lights, speed limits, and even information about buildings, which represent obstacles for wireless communication. Using our Veins simulation framework, we show that this data increases the accuracy of IVC simulation.

An Embedded System Dedicated to Intervehicle Communication Applications

To overcome system latency and network delay is essential for intervehicle communication (IVC) applications such as hazard alarming and cooperative driving. This paper proposes a low-cost embedded software system dedicated to such applications. It consists of two basic component layers: an operating system, named HEROS (hybrid event-driven and real-time multitasking operating system), and a communication protocol, named CIVIC (Communication Inter Vehicule Intelligente et Cooperative). HEROS is originally designed for wireless sensor networks (WSNs). It contains a component-based resource-aware kernel and a low-latency tuple-based communication system. Moreover, it provides a configurable event-driven and/or real-time multitasking mechanism for various embedded applications. The CIVIC is an autoconfiguration cooperative IVC protocol. It merges proactive and reactive approaches to speed up and optimize location-based routing discovery with high-mobility nodes. Currently, this embedded system has been implemented and tested. The experiment results show that the new embedded system has low system latency and network delay under the principle of small resource consumption.

Cooperative Inter-vehicle Communication Protocol With Low Cost Differential GPS

This paper describes a cooperative MANET protocol dedicated to intelligent transport systems, named CIVIC (Communication Inter Vehicule Intelligente et Cooperative). The CIVIC protocol is an auto-configuration inter-vehicle communication protocol, which supports adhoc and infrastructure networks, contains reactive and proactive routing components, and adapts different wireless standards. It is a context-aware protocol reacting to vehicle status, road traffic, and geographic environment. It supports location-based communication. To improve the accuracy of GPS, it integrates a localization solution called LCD-GPS (Low Cost Differential GPS). It has been implemented and experimented on the LiveNode sensor developed by our lab. At the end of this paper, an application project MobiPlus is introduced.

A survey of inter-vehicle communication protocols and their applications

Inter-vehicle communication (IVC) protocols have the potential to increase the safety, efficiency, and convenience of transportation systems involving planes, trains, automobiles, and robots. The applications targeted include peer-to-peer networks for web surfing, coordinated braking, runway incursion prevention, adaptive traffic control, vehicle formations, and many others. The diversity of the applications and their potential communication protocols has challenged a systematic literature survey. We apply a classification technique to IVC applications to provide a taxonomy for detailed study of their communication requirements. The applications are divided into type classes which share common communication organization and performance requirements. IVC protocols are surveyed separately and their fundamental characteristics are revealed. The protocol characteristics are then used to determine the relevance of specific protocols to specific types of IVC applications.

A Performance Study of Inter-Vehicle Communication Protocols for Collision Warning System

Collision Warning Systems (CWS) can help reduce the probability and severity of car accidents by providing some sort of appropriate warning to the driver through Inter-Vehicle Communication (IVC). Especially, the CWS can help avoid collision at intersections where traffic accidents are frequent (Study Group for Promotion of ASV; Traffic Bureau, 2007). A vehicle equipped with the CWS periodically broadcasts its information, and the CWS on other vehicles use the received information to alert drivers, helping them become aware of the existence of other vehicles. To avoid collision, the CWS has concrete objectives of IVC, i.e., the CWS should receive useful information accurately and in time. Many IVC protocols including our previously proposed relay control protocol (Motegi, et al., 2006) have been developed and evaluated through traditional metrics. However, instead of using such traditional metrics directly, many requirements of the intersection CWS must be considered to judge the feasibility and practicability of IVC protocols. This paper shows performance evaluation of our previous IVC protocol developed for CWS. To study the behavior of IVC protocols, we first describe a simulation methodology including performance metrics by means of reliable and timely communications. We then use such metrics to compare our IVC protocol with the flooding protocol in large-scale simulated networks. The simulation results show that our previously proposed protocol is a good candidate for real implementation because it passes all requirements of the intersection CWS.

Communication protocols for a fault-tolerant automated highway system

We present the design and verification of inter-vehicle communication protocols for the operation of an automated highway system in the presence of faults. The protocols form part of a fault-tolerant control hierarchy proposed in earlier work. Our goal here is to implement discrete-event supervisory controllers to stop the faulty vehicle or take it out of the highway in a safe manner. Because these actions require cooperation among vehicles in the neighborhood of the faulty vehicle, the supervisory controllers are implemented by means of inter-vehicle communication protocols. The logical correctness of the proposed protocols is verified using automatic verification tools. We discuss the safety of the proposed design in terms of the possibility of collisions and highlight the problems associated with carrying out a complete safety analysis.