Vehicle to Vehicle Communication Technology

Need of V2V:

According to WHO(World Health Organization), road traffic accidents caused death estimated about 1.20 million in the world each year. In USA over 37,000 people die in road crashes each year and additionally 2.35 million are being injured or disabled. About 450,000 accidents happen in India each year, of which 150,000 people lose their lives .India has the highest number of casualties in road accidents. There are 53 road accidents in the country every hour and one death every four minutes.

Many densely populated cities around the world suffer from traffic congestion in road systems. It is well known that traffic congestion causes many serious problems, such as fuel consumption, air pollution and the waste of time for vehicle drivers. To alleviate the problems caused by traffic congestion, two typical approaches are usually employed: widening existing roads or constructing new roads. Unfortunately, both approaches are very expensive solutions. Instead of the two costly solutions, a much cheaper alternative solution is to use vehicle route guidance systems. Owing to the rapid advances in wireless communications and global position system (GPS)-enabled devices (such as cellular phones, PDAs and car PCs), it is now feasible to make use of route guidance systems at a reasonable price. More importantly, many studies have indicated that route guidance systems can effectively alleviate traffic congestion.

What is V2V?

Vehicle-to-vehicle (V2V) communications consists of a wireless network where automobiles send messages to each other with information about what they are doing. This data would include speed, location, direction of travel, braking, and loss of stability. Vehicle-to-vehicle technology mainly uses dedicated short-range communications (DSRC), a standard set forth by the bodies like FCC and ISO. Sometimes it’s being portrayed as a WiFi network because one of the possible frequencies is 5.9GHz, which is used by WiFi, but it’s further like “WiFi”. The range is approximately up to 310 meters or up to1000 feet or about 10 seconds at speeds on highway.

On first car, V2V warnings might come to the driver as an alert, perhaps a red light symbol that flashes in the instrument panel, or an amber then red alert for escalating problems. It might indicate the notification of the threat. All that is fluid for now since V2V is still a concept with several thousand working prototypes or retrofitted test cars. Prototypes have advanced till today where the cars brake and sometimes steer around hazards. 

Vehicle based components :

V2V communication mainly requires two main components, which include one located on the vehicle and the other on the Road Side Unit (RSU). Some of the hardware components in-vehicle can be integrated into a single unit or a discrete set of components and consist of the following component, as shown in Figure

1.  Dedicated Short Range (DSRC) radio: Responsible for receiving and transmitting data over antennae.
2. GPS Receiver: Provides the vehicle position, time to DSRC radio and timing signals for applications.
3. Memory: It is Responsible for storing the security certificates with other information and application data.
4. Safety Application Electronic Control Unit (SAECU): Operates the safety related applications of the system.
5. Vehicle’s Internal Communication Network (VICN): Network that make interconnections of  comports.
6. Driver-Vehicle Interface (DVI): It displays or generates warning to the driver.
7. Security Credential Management System Manager (SCMS): Facilitates and verifies the 0461 V2V security certificates to make sure that there is trust between vehicles.
8. DSRC & GPS Antenna: Interface between the propagating radio waves and its responsible for receiving and transmitting both the DSRC and GPS signals. 

Fig.: V2V Components

How does V2V communication work?

Vehicle-to-vehicle (V2V) communication works with the DSRC (Dedicated Short Range Communications), which is a Wi-Fi type that sends brief messages up to 10 times a second over short distances, approximately about 1,000 fts. On a busy highway, automobiles may be able to send automated messages to each other communicating things like “Road is slippery,” or “Ambulance coming!” or “Traveling 74 mph, road clear.”

This technology already exists. In Japan, some of the Toyota models have V2V communication built in that conveys a few simple data points like location, speed, and heading. Soon, it’ll be common in the United States, too, as new cars and light trucks may be required to include V2V technology by 2023. Navigant Research expects “that by 2025, more than 20 million vehicles will be sold yearly with DSRC-based V2V in North America and nearly 70 million worldwide.”

What V2V could track and report :

V2V can obtain and transmit these inputs, among others. By the time V2V arrives in cars, some of may be stripped out for the sake of simplicity or cost-cutting.

• Vehicle velocity
• Vehicle position and path (direction of travel)
• On or off the throttle (accelerating, driving, slowing)
• Brakes on, anti-lock braking
• Lane changes
• Stability control, traction control engaged
• Windshield wipers on, defroster on, headlamps on in daytime (raining, snowing, etc)
• Brakes on or anti-lock braking
• Gear position (a car in reverse might be backing out of a parking stall)

Vehicle-to-infrastructure (V2I) codes and signals could transmit traffic and weather indicators:

• Traffic signal phase (green-yellow-red)
• Stop sign
• No left turn at the point of intersection
• Temperature (at a bridge that freezes over before the ground)
• Signals from cars ahead
• Approaching an emergency vehicle

Multiple sensors on multiple cars can give a truer picture of traffic ahead. If just one car has its wipers turned on, it’s likely the driver is cleaning the windshield or probability of hitting the stalk by mistake; if the majority do, it’s raining or snowing.

Unexpected braking on a dry road combined with sudden steering inputs may suggests an accident, stalled car, or obstacle on the roadway. If all the cars steer towards left, odds are the obstruction is in the right lane.

How it is different from Google Maps?

In order to move inside road between lanes(local path planning), V2X communication with a much more detailed map called HD-map must be used. The map will include lane coordinates, and objects around car(for the purpose of Localization VPS-Visual Positioning system, using objects around car that will replace the GPS-Global positioning system, with much more accuracy). With Google maps accuracy is not achieved. We also can not use the cloud to share position of vehicles in real time, because the uptime/downtime time to cloud and back to other vehicles, vehicle to cloud is just not fast enough.

The pros of V2V communication :

•        It may prevent crashes:- A majority of car crashes are caused by human error. The U.S. Department of Transportation says that car-to-car communication can help, as it has the potential “to significantly decrease many of the most deadly types of crashes through real time advisories alerting drivers to imminent threats.”

•        It may relieve traffic congestion. Imagine if all the specific data points from millions of cars were sent to a central hub. With so much real-time traffic data, transportation managers could adjust traffic light timing and redirect traffic to make rush hour flow more smoothly.  Not only that, but each individual car can use the technology to maintain a safe and consistent following distance. Imagine law enduring, organized highways, instead of hundreds of drivers jockeying for position, changing in and out of lanes.

•        It could improve fuel efficiency. A fleet of trucks stocked with vehicle-to-vehicle technology may do something called platooning: driving in close formation, like a flock of geese, to reduce drag and save fuel. Platooning effects in fuel consumption savings of up to 5 percent for the lead truck and up to 10 percent for the trucks following in formation, tests have found.

The drawbacks of V2V communication :

•        Drivers must be concerned about their privacy. V2V data can reveal all kinds of things related to you: where you’re going and when, as well as your driving habits. Who has access to this data? And how can they take benefit of it? “We have realized the hard way that both the government and private companies will go to great lengths to track vehicles—just look at the production of Automated License Plate Readers (ALPR),” the Electronic Frontier Foundation warns.

•        Liability could get complicated. Presume you are zipping along the highway and in your car, using V2V communication, tells you the road ahead is perfectly clear. Then suddenly  you smash into the back of a truck stuck in a traffic jam. Was the crash your fault? Or was it the malfunctioning of V2V tech to blame?

•        Hacking may cause chaos. The creation of V2V communication, whether in human-piloted or driverless cars, gives malicious hackers a new opportunity. Until vehicle to vehicle communication becomes a reality for everyone, the best thing you can do to protect yourself is make sure you carry dependable vehicle insurance.

 

Conclusion:

Compared to road construction or reconstruction, real-time vehicle route guidance system is a very cheap and effective approach for alleviating traffic congestion problems in urban areas. There are two types of approaches to real-time vehicle guidance: infrastructure-based and infrastructure free.

It’s evident that technology has great capabilities to help future generation transportation systems. V2V communication has unique characteristics to open doors to future generation intelligent transportation systems. The technology works great equally in V2I and V2V environments providing many mobile safety based applications. Significant encryption systems have been put in place yet there is no current security model in place that is secured enough . Studies have also indicated that there is not yet standard put in place for V2V communication . Like so many artificial made and deployments, there are some concerns in widespread deployment of V2V but day to day progress in technology and anticipated benefits can make V2V happen.

Blog Published by :-

1) Aayush Surawar ; Mechanical Engineering Department , VIT Pune.

2) Samarth Takbhate ; Mechanical Engineering Department , VIT Pune.

3) Vaishnavi Mathpati ; Mechanical Engineering Department , VIT Pune.

4) Umesh Wanare ; Mechanical Engineering Department , VIT Pune.

5) Viren Wanekar ; Mechanical Engineering Department , VIT Pune.