LIDAR technology: do you know how it works?

New car models are beginning to fit different types of driver assistance systems that improve safety while driving. These are elements that work actively, detecting the various obstacles the car may encounter. Thanks to this visualisation of the environment, the car can activate different active safety elements. One of these sensor systems is LIDAR radar.

This technology is increasingly common in the most current models and is used to detect obstacles at the front of cars. Thanks to a laser beam, the car can create a 3D map of everything in front of it. This allows it to understand the space opening up ahead and it can perform complex calculations to avoid collisions with other vehicles.

What is LIDAR?

LIDAR radar is responsible for mapping the route the car is going to travel, obtaining a 3D image and allowing other autonomous driving assistance elements to act. Unlike traditional radar, LIDAR is not based on radio waves; instead it emits a laser light that bounces off objects and returns to its source. With the calculations the processor performs on receiving that solid light beam back, it can “build” a precise image of what is in front of the vehicle.

Most importantly, it can do this at a very high speed, so it conveys that 3D image in real time. The emission of those laser beams is continuous and the reception of the reflected light is too, so it is a very reliable system with a very efficient result.

The laser emitter is located in the windscreen or elsewhere on the front of the vehicle, just like the sensor that detects the beam reflected off the object it encounters. The great advantage of LIDAR over traditional radar is that the wavelength of the laser is shorter, and thanks to it one obtains not only the distance of the object from the emitter (in this case, the car) but also information about the shape of that obstacle.

Processing that information is what allows the processor to know whether the obstacle is a vehicle, a bicycle or a pedestrian and to act accordingly. Most typically the emergency brake is activated, although this depends on the car’s technological equipment. Either way, the precise detection of obstacles through LIDAR prevents many accidents and risky situations.

The combination of several sensors and these precise types of radar is what will allow, in the not-too-distant future, full autonomy of cars.