Different Levels Of Autonomous Driving Vehicles Explained

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Different Levels Of Autonomous Driving Vehicles Explained

levels of autonomous vehicles

The different levels of autonomous driving are prescribed by SAE International, according to the degree of automation offered by the vehicle

The automotive industry is looking to reach autonomous driving eventuality, and while fully-automated vehicles for regular transit may be far away, technologies to enable it have been in development. The automated driving levels of driving automation are defined in new SAE International standard J3016. The SAE levels of autonomy define vehicle autonomy from Level 0 to Level 5, in order of the intensity of self-driving technologies incorporated into the vehicle.

What is the difference between the levels of autonomous vehicles

On a broad perspective, Levels 0-2 include the need for a human in the vehicle to drive and constantly supervise the various parameters of the vehicle, environment and other conditions. The support features offered in these forms of autonomous driving can range from limited warnings alone, right up to steering and braking/acceleration assistance. Some of the features offered in Level 0 to Level 2 autonomous cars are automatic emergency braking, blind spot warning, lane departure warning, lane centring and adaptive cruise control.

The real essence of automated driving kicks in from SAE Levels 3-5, wherein the human in the vehicle does not carry out the task of driving once the automated features are engaged. Level 3 autonomous cars will still require the driver to take over when the automated driving features requests for the same, whereas the features in Level 4 automation and Level 5 autonomous vehicles will not require the driver to take over the vehicle at any given point of time. Some of the features of automation found in Level 3-5 vehicles include traffic jam chauffeur, local driverless taxi, absence of steering and pedals, in that order. The features in Level 3 ADAS Level and Level 4 automated driving can take control of the vehicle in limited conditions and not operate unless all the prescribed conditions are met. Meanwhile, Level 5 vehicles are the ultimate form of automated driving, where the vehicle is navigating itself autonomously across all possible conditions.

ADAS: Advanced Driver Assistance Systems

Car autonomy levels depend heavily on technologies that back them up and make them a system that can be brought onto the roads in the future. It is made up of technologies such as advanced driver assistance systems (ADAS), connected ecosystem and sensor fusion. ADAS is the main foundation to a strong and safe automated driving system, which presents itself across all levels of autonomy. ADAS levels features such as Automated Emergency Braking, Adaptive Cruise Control, Lane Departure Warning, Blind-Spot Detection, Forward Collision Warning, Traffic Sign Recognition, Tire Pressure Monitoring System, Night Vision, Pedestrian Detection and Parking Assistance enable various levels of car automation.

These ADAS features are infused into vehicles to enable the desired car autonomy levels. These systems collect data regarding the vehicle, driver and surroundings through various receivers, such as camera, radar, LIDAR and navigation maps to then analyse the situation and then take appropriate decisions, in terms of driving. This shows that the vehicle needs to be connected to other vehicles on the road, as well as to the overall infrastructure for different types of information related to the road and conditions. The degree to which the vehicle and its systems are connected to each another, as well as to other vehicles and multiple information-providers becomes very important. Such information needs to be analysed, and resulting steps would facilitate in the decision-making aspect of autonomous vehicles.


While the adoption of ADAS systems that leads to vehicle automation levels is definitely on the rise, but the practical usage of these systems in the real-world calls for development of overall road infrastructure, as well as that of vehicle connectivity. In addition, regulatory mandates of safety features in vehicles would also help enhance the application and adoption of such systems that help in bringing in different levels of driverless cars into the market. The growth for technologies of vehicle-to-everything (V2X) connectivity and sensor fusion will back the ADAS solutions needed for the different SAE ADAS levels of autonomous driving.

Therefore, it could be said that Autonomous Driving Levels 1 and 2, and to some extent even Level 3 ADAS would be seen being deployed slowly in automotive markets across the globe over the next few years. Deployment of these initial levels of automated driving may be seen in the mid to high-level personal passenger vehicle space in the beginning. This is because these segments of the automotive industry are open to adopting new technologies at an additional cost much before the mass segment does. These segments of the industry generally pay a premium for technologies that they feel bring in additional value to the product, in terms of safety and technology.

Meanwhile, adoption of self driving car Level 4 autonomy and eventually autonomous car Level 5 cannot be expected any time soon. These may be stray cases of fully-autonomous vehicles plying on open roads for personal use in pockets of small countries across Europe, US and Asia. However, the case of such technologies being put to use in restricted and repetitive automotive roles is much higher. For example, the use of autonomous trucks in mines, which have fixed routes and repetitive tasks, or that of autonomous tractors to plough a set area of enclosed land will be seen first.