Visible light communication could simplify car electronics

Engineers at Warwick University are researching how to replace the complex wiring inside cars with devices that communicate via light signals.

A team led by Prof Roger Green is planning to demonstrate how visible light communication (VLC), which is already used as an alternative to wireless internet transmissions, could simplify and lighten the electronic systems in cars.

The researchers want to focus on how to transmit the beams of light around corners, how the materials inside the car affect the signals as they are transmitted and how to adjust those signals accordingly.

‘There is a lot of weight and a lot of work required to transfer signals around a vehicle,’ Green told The Engineer. ‘But there are also lots of spaces that light signals could be sent through: air-conditioning ducts, hollow doors and engine compartments that could be illuminated.’

VLC is a method of encoding data with light from an LED that switches on and off faster than can be seen with the human eye. It works in a similar way to optical fibres but transmits the signals through the air to a sensor.

The technology can be used to turn LED room lighting into wireless internet routers and is being explored as a way of allowing cars to communicate with each other via their headlights.

But Green argues that it also has advantages for sending information between the many computerised systems inside modern vehicles, partly because in an enclosed space the signals do not have to compete with natural light.

The advantage over traditional radio frequency wireless communication is that the light signals are not affected by electrical interference created within the vehicle and are not subject to telecommunication regulation.

This means multiple light frequencies, including infrared, could be used to transmit high volumes of information. The challenge will be developing ways to secure the beams as they travel around inside vehicle.

‘We need to think about what happens to the light when it reaches a corner and how much it is reflected, what colours of light we need to use depending on the coating inside the pipe,’ said Green.

The team plans to begin demonstrating the control of different vehicle components such as brake servos using VLC and is looking to work with industrial partners on the concept.