Openpilot is DIY Autopilot for Any Car by Comma.ai

Comma.ai Comma Two running openpilot
Comma.ai Comma Two running openpilot

In September 2015, George Hotz, a famous Apple hacker, founded Comma.ai with the goal of creating an Autopilot-like system that could be adapted to almost any modern car. Most vehicles sold today have drive-by-wire capabilities with the ability to control steering acceleration and braking. So it made perfect sense to Mr. Hotz that these vehicles could be upgraded with a DIY kit to support more robust Autopilot capabilities than they ship with initially.

Now Comma.ai has a full hardware and software package (using openpilot) that brings Tesla Autopilot features to modern cars. Some YouTubers have even compared openpilot vs. Tesla to see how they perform.

In this article we’ll detail the Comma.ai openpilot solution and how it compares.

Early Days

Initially, the company hit several roadblocks after government regulators prohibited the sale of the device due to noncompliance with regulatory standards. So Comma.ai open-sourced the software, called ‘openpilot’, making it available to the public.

Open Source

The goal of open-sourcing the software to democratize and accelerate the rollout of self-driving features which ideally help reduce driver fatigue, errors and accidents. Rightfully so, government agencies have been hesitant to unleash self-driving cars on the public, so engineers and hackers have

Openpilot Software

While other auto manufacturers have cautiously added features, Comma.ai and the community have been improving openpilot.

To be clear, openpilot is a Level 2 software system (see What are SAE Self-Driving Levels?) and requires constant driver attention. Importantly, it’s not a self-driving system (think Waymo) and is more like other cars with autopilot in that it is primarily Adaptive Cruise Control (with stop-and-go capabilities) along with Lane Centering.

It achieves this magic by talking to the vehicle’s CAN bus that manages sensor and vehicle control data. By tapping into the CAN bus, openpilot is able to sense the environment and respond to it by maneuvering the vehicle.

New Comma Two Hardware

The big news is the new hardware package. In addition to the openpilot software, Comma.ai released a new version of its hardware, called Comma Two, making installation relatively plug-and-play. It’s available starting in late January on the company’s website as a developer kit. It includes a souped-up cell phone with cameras to monitor the road as well as the driver to ensure the driver is watching the road. The device attaches below the vehicle’s existing Lane Keeping camera.

Comma.ai Comma Two Hardware
Comma.ai Comma Two hardware mounted below rearview mirror

If the infrared sensors that monitor the driver detect that the driver is not paying attention, the system will issue an alert and eventually stop the vehicle if the driver is not responsive.

The device itself is essentially a high-end OnePlus cellphone inside a custom case that provides the ability to mount it on the windshield and also embeds additional sensors, like a rear-facing camera and the infrared driver monitoring sensors

Comma.ai Comma Two Hardware Front
Comma.ai Comma Two Hardware Front (inside-facing)

The ‘rear’ portion of the case contains the rear camera from the phone plus a cable connector and the phone mount:

Comma.ai Comma Two Hardware Back
Comma.ai Comma Two Hardware Back (facing outward)

Comma.ai also includes all the cables required to connect the cell phone to the car’s built-in camera/radar detector on the windshield as well as the vehicle’s OBD-II ports.

Comma.ai Comma Two Wiring Kit
Comma.ai Comma Two Wiring Kit

The actual installation is no more difficult than installing a traditional dashcam in your vehicle as demonstrated in their installation video:

Limited Set of Compatible Vehicles

The openpilot and Comma Two system only works with certain cars that already have basic Advanced Driver Assistant System (ADAS) built-in, about 60 or so vehicles, some, like the Honda CRV built as early as 2015. The full list is on their website. In addition, openpilot works in conjunction with those systems and in some cases may be limited to their capabilities (e.g. at which speeds certain features work).

If you are a developer, you can actually join the development effort to bring openpilot to more vehicles.

Autopilot Capabilities

As mentioned above, the openpilot system works in conjunction with the car’s ADAS and enhances it. Depending on the car’s features, certain capabilities may be limited. Here’s a brief overview.

Improved Adaptive Cruise Control & Lane Centering

Like most all cars with autopilot (Tesla excepted as they are pushing for more autonomy), these systems are basically better Adaptive Cruise Control (ACC) and Automated Lane Centering (ALC). Where previously these systems were highway only (many still are) and warned you if you depart the lane, most now actively keep you centered.

What openpilot does is to enhance those capabilities. So if your car’s ADAS capabilities don’t include stop-and-go in traffic, openpilot will add it, for example.

Device Camera Used

While your car may have a built-in camera, the Comma Two kit with openpilot utilizes the camera within the cellphone utilized by the hardware.

Comma.ai Openpilot Camera
Comma.ai Openpilot Camera

Radar from Vehicle

Unlike the camera, which openpilot uses from the device, the vehicle’s built-in radar is utilized to help determine the distance to objects in front of the vehicle.

Comma.ai Openpilot Uses Vehicle Radar
Comma.ai Openpilot Uses Vehicle Radar

Engaging openpilot

You engage openpilot using your vehicle’s controls and disable it by pressing a pedal or pressing Canel on your vehicle’s control.

How to engage openpilot
Engage Openpilot with your Vehicle’s Set button

Driver Monitoring

Driver monitoring is an important part of any autopilot or Advanced Driver Assist System (ADAS), and rather than just checking for a hand on the wheel, openpilot thankfully uses a more sophisticated and robust technique of face monitoring.

Openpilot Driver Monitoring System (DMS)
Openpilot Driver Monitoring System (DMS)

Dangerous Lane Changes?

One surprising feature supported by openpilot is assisted lane changes. While other manufacturers such as Tesla and BMW support this feature, they only change the lane when it’s clear to do so. Not the case with openpilot. It will automatically change lanes after you engage the turn signal and nudge the wheel, but requires that the driver ensure it’s clear and safe to do so.

Openpilot Lane Changes
Openpilot Lane Changes

We’re not sure why this is even included, as it could lead to confusion and potential accidents. Either way, driver beware!

Demos at CES 2020

Comma.ai was at CES 2020 and provided demo rides to journalists. Here are a couple of videos that provide hands-on experiences:

First a quick overview from Engadget:

Openpilot vs Tesla Autopilot

Then there is an interesting, in-depth side-by-side comparison of a slightly older openpilot version with Tesla Autopilot below.

Note that the reviewer here incorrectly compares openpilot with the Tesla Autopilot Full Self-Driving (FSD) package that costs $7,000. That’s not really a fair comparison since Autopilot is included for free with new Tesla vehicles (see Autopilot and Full-Self Driving review) and the only thing FSD provides is automated lane changes, which openpilot doesn’t fully handle anyway (see Autopilot vs Full Self-Driving – Worth It?)

Our Take

While this is very interesting, the functionality is heavily dependant on the vehicle, so the market is likely fairly small, especially as auto manufacturers begin to include more of these features themselves in the coming years.

We love self-driving technology and the open-source community around this project, but this is probably best-suited for technology-savvy drivers who enjoy hacking their car and want a bit more of the Tesla Autopilot-like experience in their everyday driving.

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