Vince Tabora
Feb 24, 2018 · 8 min read

The Tesla Autopilot is a feature that is provided for SAE Level 2 semi-autonomous driving. It is a form of ADAS or Advanced Driver Assistance System that provide ways to assist the driver using a variety of high tech features. These are available on the current Tesla models. The Autopilot is now marketed as Enhanced Autopilot after it was optimized and new features were added. The purpose is not just for self driving, but to increase safety for the car and its passengers. A driver is still required for Level 2 cars, since the vehicle is not fully capable of autonomous operation. That means the most critical decisions when driving are still determined by the driver and is not the responsibility of the car. Though it is not fully autonomous, the hardware on Tesla’s EV line up are capable of self driving. The updated hardware for Enhanced Autopilot is called Hardware 2 or HW2 and has a set of specifications that improve upon the original design.

Tesla has updated to software version 8.1 (March 2017) with some October 2017 updates which aims to deliver among others things, improved Autosteer up to 90 mph, Traffic-Aware Cruise Control, Summoning, Auto Lane Change and Speed Assist. There were also updates to AutoPilot 2.0 and AutoPilot 2.5 hardware. One important feature to this update is Automatic Emergency Breaking. Update 2017.42 features some further improvements. This includes more awareness while driving off freeway and on urban roads.


The hardware consists of cameras and sensors that provide what is called Advanced Sensor Coverage (ASC). This system consists of 8 cameras that provide 360 degrees of visibility around the car at up to 250 meters of range. The cameras use machine vision with AI software along with 12 ultrasonic sensors that can detect and identify objects. A front facing radar is also used to be able to sense the surrounding in heavy rain, fog and dust.

A diagram of how the Enhanced Autopilot works.

According to specs, the 8 cameras are used for the following:

1 Narrow Forward Camera — Focused for maximum distance of 250 meters.

1 Main Forward Camera — Focused for maximum distance of 150 meters.

2 Forward Looking Side Cameras — Focused for maximum distance of 80 meters.

1 Wide Forward Camera — Focused for maximum distance of 60 meters.

2 Rearward Looking Side Cameras — Focused for maximum distance of 100 meters.

1 Rearview Camera — Focused for maximum distance of 50 meters.

The cameras provide a 360 degree view around the car at varying distances. The narrow forward cameras provide long range view and are useful for high-speed operation. The wide cameras have a larger angle using a 120 degree fisheye lens to capture close range objects like lights, other cars and obstacles on the road. The main camera cover a broader range of the road directly in front of the car, much like how the driver sees the road. The radar system is added to sense objects that machine vision cannot resolve, by bouncing radio waves that can cut thorough tough to see places with a 525 foot range. Finally, ultrasonic sensors are added with improved sensitivity using uniquely coded signals that can detect things at a 26 foot range. These sensors are useful for detecting nearby cars and provide guidance with parking. The system combines vision, radio and sound to detect its surrounding. This mimics how a driver sees the road, but Autopilot hardware can see more of what a driver is not able to see. This also forms part of what is called Tesla Vision.

An onboard computer on the car processes all the data from the sensors and cameras. It is a Tesla developed neural net software that makes use of computer or machine vision that is built with NVIDIA’s GPU CUDA. The computer system uses NVIDIA’s Drive PX2 system. The updates to the software are also done automatically over Tesla’s wireless network. The Tesla Vision system remains the most sophisticated among EV makers to date.


Autopilot brings Semi-Autonomous Driving

Let’s analyze some of the features that make Enhanced Autopilot (Software Release 8.1 and higher and using Hardware 2 or HW2 and higher).

On-Ramp, Off-Ramp — This allows the car to exit off the freeway or highway by identifying the best lane to drive on. This is determined by the navigation system’s destination which the driver specified. After the car exits, the control is returned to the driver.

Autosteer — The car’s position is maintained within a lane and allows the driver to briefly remove their hands from the wheel. It’s restricted to 90 mph and below on HW2, up from 45 mph. Autosteer requires the driver keep their hands on the wheel and be prepared to take over at any time. The main use of Autosteer is lane-keeping which makes the car stay on a lane and cruise. The car also has the ability to change lane when driver uses turn signal and safely exit using the on-ramp, off-ramp feature.

Smart Summon — When the car is in tight spaces, like a parking lot, and the driver does not have enough space to open the door, the summon feature allows the car to pull out of the parking spot. This also allows the car to come to the driver rather than the driver coming to the car. It is also called remote automatic car retrieval.

Self-parking — This requires locating a parking spot, and accelerating about 4–5 mph with the self-parking activated. The car with Level 2 capabilities, will then maneuver the steering wheel and control the brakes to park itself without driver intervention.

Adaptive Cruise Control — This gives the car the ability to follow another car and maintaining a safe distance from it as it speeds up and slows down. It can also observe another car in front of the car that it is following. It also slows on tight curves on the road and when a car crosses in front of it. This feature is enabled at any speed above 17 mph. By default, it sets the limit at the current speed +/- specified offset.

Auto Lane Change — This is activated when the driver signals for a lane change. The Enhanced Autopilot than takes care of changing lanes on the road, which is guided by the ultrasonic sensors. It can also be sone automatically in HW2 without the driver’s control when the car detects slowdown and moves to a faster lane.

Full Self-Driving Capability — This would bring the car to a Level 5 full autonomous vehicle. That means it is fully self-driving aware. Tesla provides this feature for an additional charge. Besides being able to drive itself, the car will be able to automatically recharge at “cable bot” equipped Superchargers and can use Parking Seek to find a parking space by itself.

Alert System — For the purposes of safety, this feature is used to provide visual and audio alerts to the driver. This will happen in the event the car needs the driver’s attention and control for making decisions that require human intervention. If the driver dismisses 3 audio warnings within an hour, Autopilot is disabled until the car is parked. This can help prevent accidents when the car detects a problem which the driver can react to much better using their judgement. Other system warnings can be related to low battery, tire problems and other issues that are related to the car itself.

Collision Detection and Safety — A potential front or side collision with another car, bicycle or pedestrian within a distance of 525 feet, will sound a warning. Autopilot can use automatic emergency braking that detects objects the car might hit and applies the brakes. Autopilot also can automatically adjust the high/low beam headlights for night driving conditions.


Tesla Model S P100D

I had the opportunity to test drive a Tesla Model S P100D from Tesla in Las Vegas. The P100D is luxurious indeed, spacious and very stylish. During the freeway test, when Autopilot is enabled, you can let go of the steering wheel and the Tesla Vision software takes control. Unlike most autonomous vehicles that use LIDAR, Tesla uses cameras that process MV (machine vision) with intelligent sensors which gives it an awareness of its environment for safety. It has a collision detection and avoidance system that calculates when you will collide with the vehicle in front of you so it applies automatic braking control to allow you to steer to safety when using their adaptive cruise control. Now when you let go of the steering wheel with Autopilot, the car is STILL NOT FULLY AUTONOMOUS.

You can intervene anytime to disable Autopilot and I found I had to do that a few times because I felt uncomfortable letting the car drive on its own. I wanted to test the self driving capability so then I decided to give it try, after all Tesla guarantees its reliability to a high probability of success. On the 215 freeway, I plotted the Tesla navigation to exit off to the 15 S heading to Los Angeles. I engaged Enhanced Autopilot by clicking the lever twice on the left hand side of the wheel. The car started driving by itself. With my hands away from the wheel, I signaled a lane change to exit. Autopilot then made a lane change without me steering the wheel and managed to also exit without any incident. You then realize, this thing can really pretty much drive itself. You still have to guide the car in certain situations like when you want to change lane by using the signal light. We ended the test drive with the summoning and self parking feature. With self parking, you have to locate a spot first, then enable the feature and drive a minimum of 5 mph toward the spot. The Autopilot then does the rest for you. I would say it still takes some practice for the driver to get this right, but I was able to do it twice. Self parking is not new in the auto industry, but the way Tesla does it seems so effortless.


The new features on Enhanced Autopilot not only deliver on new capabilities in driving technology, but also aims to increase safety. This addresses issues like driver fatigue, handicap and even negligence. It is still the responsibility of the driver to pay attention to the road, since the Level 2 features on the current Enhanced Autopilot still don’t guarantee full self-driving capabilities. While most of the features provide more advanced capabilities, the driver must not be too dependent on them. Level 5 promises to allow full self-driving, to the point where the driver can sleep while the car drives itself. That feature however, has not matured enough at this point to conclude it is fully safe. There are still many things evolving in the self driving car industry with the goal of making the technology better. There are also legal, regulatory, and technical hurdles to overcome to accomplish this goal.

Self-Driving Cars

A publication covering news, predictions, and opinions about self-driving cars and other autonomous vehicles.

Vince Tabora

Written by

Electrical Engineering, Data Science, Photography, Blockchain, AI, Cybersecurity, Multimedia, EV and Autonomous Vehicles

Self-Driving Cars

A publication covering news, predictions, and opinions about self-driving cars and other autonomous vehicles.

Welcome to a place where words matter. On Medium, smart voices and original ideas take center stage - with no ads in sight. Watch
Follow all the topics you care about, and we’ll deliver the best stories for you to your homepage and inbox. Explore
Get unlimited access to the best stories on Medium — and support writers while you’re at it. Just $5/month. Upgrade