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Comment by chrisper | Hacker News Reader

Are your choices based on hackability or something else?

The hackability comes with the car doing most of it's internal communication via a CAN bus and having enough electrical power to power your custom electronics.

Apart from that, the car needs to have Steering by wire, Gas/Brake by wire and Shift by wire. Lane Keep Assist and Adaptive Criuse Control in those models mean that the car can be ordered to steer or accelerate via the can bus without additional actuators.

I have been learning about that topic for about a year and a half and the reason I recommend those specific models is because I have seen autonomous driving companies pick those specific ones without official support from the manufacturer.

Steering by wire --> none of the cars you listed have steer by wire. Nissan is the only OEM who has steer by wire in production. Brake by wire --> does not exist at all.

You are right in the formal sense, none of those cars officially have by-wire functionality but in order to have LKAS, Park Assist and ACC work they need to support steering via can bus messages and braking via can bus messages. I used by-wire in an informal sense. Disclamer, I have never worked in the car industry, that's why my terminology is a bit loose.

ingenieroariel is being humble here. He is one of the first (if not the first) to do this with the Ford Fusion.

https://github.com/commaai/openpilot/issues/1

Work on the Lincoln MKZ / Ford Fusion was made popular thanks to Dataspeed / Autonomoustuff, they open sourced a ROS module but most of their magic is propietary / secret. It's expensive but a lot of startups use it.

The work that you point to is what we now know "openly", and yeah, there is only a few of us and I am one of the firsts sharing their findings on that specific model. There are a ton of people who know what we yet don't know but they don't/can't share it publicly.

While no cars have brake by wire, the computer can stop the car using mechanical actuators already(ABS is exactly this, or the more modern emergency breaking system) - same with steering, plenty of cars have "parking assist" where they park themselves, so the computer must be able to control the steering even if it's done by mechanical means.

Every car that has an lane assistant or a parking assistant with automatic steering, and there are number that do support either of those, is having some sort of steer by wire. Even the lane assistant is normally designed to give you a force in the steering wheel to keep the lane. That you can reuse for automatic driving of some sort.

Wasn't Mercedes SBC brake-by-wire during normal operation? (They have since abandoned it, but it saw service in production cars in the early 2000s.)

I can’t speak to his rationale, but all of these are relatively affordable vehicles that take advantage of a lot of the newer technologies that tie into the CAN bus. Additionally, they expose interfaces to many of the onboard computers connected via CAN through the DLC connector, and off-the-shelf hardware exists for Toyota and Honda vehicles to expose the rest of the bus through the DLC connector, which is not particularly useful for typical scan tools, but it does allow for comma.io’s panda dongle to dump pretty much all of the information being passed around on the CAN bus.

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