Autonomous driving and ADAS is the part of a car that sees the road and brakes or steers by itself. ADAS stands for advanced driver-assistance systems. It covers everything from a car that brakes when a crash is about to happen to a taxi that drives with no one at the wheel.
The car first has to see. The cameras, radar and lidar measure the road around it. Cameras read signs and lane markings. Radar measures the distance and speed of objects. Lidar builds a three-dimensional picture with laser pulses.
Software then has to understand what the sensors show. In a car that only assists the driver, driver assistance systems brake in an emergency, keep the car in its lane or hold a safe distance from the car in front. The driver still drives. In a car that drives itself, autonomous driving software recognises vehicles and people, plans the path and controls the steering and brakes. The industry sorts all of this by levels of autonomy, which describe how much the car does and how much the driver does.
Such software cannot be tested only on real roads, because dangerous situations are rare and cannot be staged safely. So companies first test in autonomous vehicle simulation, over millions of virtual kilometres. A self-driving car also needs a precise map, an HD map, that shows each lane.
The two kinds are at very different stages in India. Driver assistance is already sold: many new cars offer it, usually as an option on costlier models. Driverless cars are not. Driverless taxis run today in some cities in the United States and China, and no Indian city has one. So most full self-driving work is done abroad, while Indian engineers build maps, simulation and testing for it.
India is also one of the largest markets for two-wheelers, so assistance for scooter and motorcycle riders, described under rider assistance, is a natural place for Indian start-ups to begin.