Move steering wheel using VCDS
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Impossible to answer without knowing more about the car, best would be a VCDS Auto-Scan - if you don't have VCDS (yet!) maybe there is someone living close to you who does?
I doubt that moving it to a specified angle is something that is supported by the diagnostic API in any of the modules.
I believe it is possible to request the steering assist to apply torque in either direction with messages directly on one of the internal buses, but that such messages would not make it from the diagnostic socket through the CAN gateway to the appropriate internal bus.
-Uwe-
I believe it is possible to request the steering assist to apply torque in either direction with messages directly on one of the internal buses, but that such messages would not make it from the diagnostic socket through the CAN gateway to the appropriate internal bus.
-Uwe-
Maybe I was too specific about the angle - just "move more right" or "move more left" should be enough from my perspective. The rest could be handled by calibration/feedback mechanisms.
Do I understand correctly from your words that there is currently no known way to move the steering wheel through the OBD port or is it just not yet handled by VCDS?
What I am wondering about in general is whether it would be possible to have third party software based park assist. As an input it would have eg. cameras and then it could move the steering wheel to handle more advanced cases.
Do I understand correctly from your words that there is currently no known way to move the steering wheel through the OBD port or is it just not yet handled by VCDS?
What I am wondering about in general is whether it would be possible to have third party software based park assist. As an input it would have eg. cameras and then it could move the steering wheel to handle more advanced cases.
I suppose this would be possible. See for example OpenPilot. However, my understanding is that it needs to tap into the car's internal buses.
@jyoung8607 would know more.
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I'm not aware of any mechanism to apply steering torque or angle commands via the DLC, using VCDS or any other tool or method. There's no provision for doing so within the diagnostic protocols, and the CAN gateway won't forward the required message types to or from the DLC that various driver assist features use to make it happen. You would have to connect directly into one of the internal CAN buses.
If you really wanted Park Assist, I think it's well understood in the community how to retrofit it using factory methods.
If you're exploring this for personal nerdery reasons, yes, it's possible to insert something in the communications channels used by the Lane Assist or Park Assist features, even if the car didn't have those features from the factory. That's how I made openpilot work on Volkswagen, MITM of the Lane Assist steering messages.
Ok, clear now. Thanks a lot.
My car already has factory installed Park Assist. The issue is that it does not work for a parking scenario that will be common for me (my own parking space that has only 10cm space on either side of the car).
Yes, I would call it my own nerdery reasons :-) It starts getting off-topic here, but could you share any more info on having openpilot work with VW (I guess there would be significant similarity to Seat).
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Not saying it can't be done, but I'd be interested in seeing video.
All MQBs in the VAG family, except some nuances for MQB-A0, work identically for this purpose. There are three external control channels into the steering rack:
* DSR (for ABS/ESC intervention only), takes an angle and/or torque input, you don't want to mess with this
* PLA (Park Assist), usable only at low speeds, takes an angle (and maybe torque, not sure), this is probably what you want
* HCA (Heading Control Assist a.k.a. Lane Assist), takes limited torque input only, not an angle, not usable at a dead stop
You'll need something to send PLA messages to the steering rack, directly on the same bus as the steering rack since I believe the PLA module sits on the same bus with it by design, so the gateway isn't likely to forward that message from any of the other onboard buses. If you disable your factory PLA, you can just tap into the bus and listen/inject. If you intend to retain your factory PLA, you'll need something to intercept and filter its messages at the times you want to use your own.
openpilot uses HCA rather than PLA, and I don't have a decoded version of the PLA message for you, but it wouldn't be rocket surgery to figure out. I believe I do have decoded versions of stuff like the ultrasonic sensors (Parkhilfe_01), the rear cross traffic assist radars (RCTA_01), and most all the other car state goodies you'd need if you're serious about it.
If you get to the point of tapping into the running gear bus, here's a secret decoder ring that might be of help to you. It's kind of a mishmash between a couple different information sources that I was able to acquire, and some stuff I reverse engineered over time. It's not complete but it's got 95% of the important stuff.
opendbc/vw_mqb_2010.dbc at master · jyoung8607/opendbc
democratize access to car decoder rings. Contribute to jyoung8607/opendbc development by creating an account on GitHub.
github.com
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Maybe there was a misunderstanding - it is perpendicular parking so it is certainly doable manually, even if the space to position the car is limited. Not very comfortable though. And as one guy pointed out - sooner or later you will break side mirrors.Not saying it can't be done, but I'd be interested in seeing video.
Do you know if there is any publicly available information how to actually find the correct wires for PLA CAN bus? And which CAN to USB hardware would you recommend? I mean anything that starts with a stock VAG car and end with CANdevStudio ready to intercept/replay messages. I do have some experience with protocol reverse engineering (recently did some work on Android Auto), but I am not very familiar with VAG CAN cabling just yet.
Do you think that if I send steering wheel position messages it would interfere with PLA module (of course if the "start parking assist" button is not pushed)?