How Do Self-Driving Cars Work?

Tech companies and auto manufacturers have long been racing each other to be the first to usher in the era of the self-driving car.

Self-driving tech was recently rolled out by a few auto manufacturers in the form of an “Automated Valet” feature. The idea is that it provides full valet parking services that allow their vehicles to drop drivers off at the entrance, find a place to park and pick the driver up when hailed by an app. However, the tech is still very much in the refining phase.

We’re a long way away from fully automated driving being commonplace on the roads, but here’s how they work:

What Kind of Vehicle is Considered a Self-Driving Car?

Provincial governments create traffic laws and are responsible for regulating vehicles using public roads and highways. In Ontario, self-driving cars, or automated vehicles (AVs), are defined as “a passenger motor vehicle, commercial motor vehicle or a streetcar with an automated driving system that operates at the Society of Automotive Engineers (SAE) driving automation Level 3, 4 or 5.”

The SAE classifies all motor vehicles, including those without any self-driving features. These are the six levels of driver automation and how they are classified:

  1. Level Zero: No Driving Automation.
  2. Level One: Driver Assistance
    • The vehicle can assist the driver with simple jobs, like accelerating, braking and steering. Most vehicles on the road today come with features that place them in this category.
  3. Level Two: Partial Driving Automation
    • Motor vehicles in this category have two or more automated functions, like cruise control and automatic braking, that can work simultaneously. Level two vehicles still require the driver to be fully engaged behind the wheel.
  4. Level Three: Conditional Driving Automation
    • Level three vehicles can self-drive in specific situations, mainly on highways, but the driver is still required to remain attentive and ready to take over at any moment.
  5. Level Four: High Driving Automation
    • These vehicles can drive themselves and do not require a human operator in certain situations.
  6. Level Five: Full Driving Automation
    • This would be a fully self-driving car that we see in movies about the future. A level 5 vehicle is fully autonomous in all conditions and scenarios.

Ontario’s Automated Vehicle Pilot Program began back in 2016 as a 10-year program to allow testing of automated vehicles on Ontario roads under strict conditions, including the requirement of having a driver in the vehicle. That was changed in 2019 to allow testing of SAE Level 4 and 5 vehicles on Ontario roads without a driver (with conditions.)

How do Automated Vehicles Work?

AVs use a combination of Radar, Lidar and high-resolution cameras to scan the area and “see” all surrounding objects like other vehicles, pedestrians and curves in the road.

The AV’s computer then combines the scanned data with the information gathered by its sensors, GPS and Inertial Measurement Unit (IMU) input (that measures the AV’s force, angular rate and orientation). By aggregating all that data, the AV builds a map of the surrounding area and is able to place itself inside the map to understand its relative position to other objects within the map.

To carry out the actual driving, an AV plans paths to its destination. It first creates a long-range plan similar to GPS and map applications. As it drives, it’s continuously generating short-range plans and refining them as needed.

The AV is also continuously drawing maps of its surroundings, including all visible and predicted obstacles and using machine learning to identify certain objects and their predicted behaviours. This allows it to distinguish objects from each other and decide how to avoid them.

When they are fully deployed, the idea is for them to continually share data with each other to help them avoid hidden obstacles.