Our series on the Future of transportation explores innovations and challenges that affect how we move around the world.

A good relationship depends on communication. Silence dominates when it comes to vehicles and their owners.

Except for a few vague warning lights on the dashboard and side mirrors, and a few sensor-based sounds in some recent models, drivers know nothing about what the vehicles and pedestrians around them are about to do. A dangerous obstruction in the roadway, two cars about to move into the same lane, or a bicycle coming out of a blind alley are a few potential surprises that the driver may not know about.

By the end of the decade, many of the surprises are expected to change. C-V2X is shorthand for cellular vehicle-to-everything technology and is being developed by manufacturers for vehicles to communicate with each other and pedestrians.

V2X technology will give drivers time to take evasive maneuvers if a car's cameras detect a potholes in the road. A vehicle that is travelling too close to a highway worker will be warned. If a vehicle fails to stop, school bus drivers will not let children off. Bicyclists and drivers will be aware of each other.

While passive safety such as seatbelts and active safety from such things as lane departure warning has improved occupant safety, the number of deaths outside the vehicle are growing. Sharing safety-related information with others is one of the things we are trying to do.

Vehicles that can communicate with school buses, highway workers and cyclists are being tested in Georgia and Virginia. C-V2X test vehicles were able to detect stopped school buses, vehicles running a red light, construction workers in the road, and bicyclists in blind spots. The C- V2X vehicle could be detected by those vehicles and people.

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A cyclist with a V2X sensor drove across the path of an audi e-tron in a recent demonstration There was a warning sound and icon on the instrument panel before the cyclist was seen by the driver.

Increased safety can be achieved by vehicle communication. Some cars in the U.S. can communicate with traffic lights with a green light on the instrument panel. Knowing when the light changes can make driving in stop-and-go traffic easier.

These warnings can be heard on a vehicle's instrument panel, a hand-held device in a jacket, or on a phone. Automatic emergency braking can be incorporated into the V2X system.

Johannes Springer, the director general of the 5GAA automotive association, said that V2X technology could be used for "geofencing." He said that when excess emissions are detected in the atmosphere, a hybrid vehicle that is tracked could be ordered to drive only in electric mode.

Ram Iyer is a senior vice president at Harman International, a supplier of vehicle technology. You will look for these technologies to save your life.

Vehicles with V2X technology are expected to be on the market in the next few years. Most of the vehicles that can communicate will be talking to themselves.

ImageA blue car heading toward a man on a bike crossing the street. In the top right corner is a rendering of the dashboard of the car, showing a “warning: bike” icon.
One V2X scenario in an Audi: a cross-traffic bike alert, noted on the car’s dashboard.Credit...Audi
A blue car heading toward a man on a bike crossing the street. In the top right corner is a rendering of the dashboard of the car, showing a “warning: bike” icon.

Some vehicles in China already offer V2X, but with limited features, such as warnings about possible crashes and traffic jams. In Europe, certain Volkswagen models offer a different form of V2X technology, known as Car2X, which can inform each other of critical traffic situations, including broken-down cars and approaching ambulances.

There are still hurdles to overcome for V2X technology to be offered by many manufacturers. V2X technology for new vehicles was initially recommended by the U.S. government, but it was revoked by the Trump administration. The spectrum that the FCC had assigned for V2X communications was reallocated for other uses. The Alliance for automotive innovation disagrees with the position taken by the F.C.C. that C-V2X technology is pointless because of the increasing ubiquity of in-vehicle sensors and cameras.

Hilary Cain is the vice president of technology, innovation, and mobility policy at the alliance. Technical rules for C-V2X are still being worked on. V2X is important because it can see around corners and through things.

To avoid transmission delays, vehicles will talk to each other directly, not through cellular transmission towers. The system will switch to 5G standards eventually.

V2X safety features will be free.

I have never heard of an auto company planning to profit off of this safety technology. It is a technology of cooperation. Vehicles will be able to communicate with each other.

V2X will make an enormous contribution to safety, according to Maite Bezerra, a smart mobility and automotive industry analyst.

There are a lot of accidents that could be avoided. Fuel efficiency will be improved due to warnings of traffic jams and red lights.

Governments around the world have not mandated the use of V2X. V2X will be included in the New Car Assessment Program in China and Europe.

V2X standards have not been promulgated by the F.C.C. in the US. Several state departments of transportation and equipment manufacturers have requested a waiver from the F.C.C. in order to offer C-V2X technology in their vehicles. The waiver request hasn't been acted on.

The industry is not sitting still. V2X transponders for cyclists are being worked on by AUDI and the company expects to begin offering V2X in its vehicles in the 20th century.

Mark Dahncke is the director of product communications for AUDI of America.

Someone will make it all worth it if they send a letter saying they saved my life.