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I need to read vehicle steering angle (front wheel angle) data in real time for a research project that I am involved in. How can I achieve that? What HW and SW do I need for it?

So far I can think of 2 ways of doing it:

Option #1

Custom measurement hardware/sensor mounted directly on steering close to a front wheel. This may be rather complicated in terms of custom HW design and fitting it to the car. An advantage will be easy sensor reading since the sensor used would have a known output data format.

Option #2

Trying to read from the steering angle sensor (SAS) just on the steering wheel. I guess it can be read from CAN bus via OBD2 interface? I need to access the data from my C++ code in Linux.

I can purchase a used vehicle for the purposes of the project. Will someone have suggestions on vehicle makes and models which may be able to provide the SAS data? My location is the European Union. I would prefer Volkswagen Group vehicles (VW, Audi, Seat, Skoda) but that is not a must.

From what I have read only vehicles with Electronic Stability Control (ESC or ESP) are equipped with an SAS.

Edit:

After further search I found that steering angle data is not part of standard ODB PIDs so it can only be obtained with specialized software. This means the market will most likely be fragmented somehow. However, I also found the open source OpenXC platform by Ford, which makes steering wheel angle parameter available for some Ford vehicles. They even have a C library for interfacing to the vehicle.

  • To summarize after some time: the OpenXC may be the best overall solution working for multiple car models. Beyond that, one has to sniff and decode the CAN bus of particular car - some may provide the data and some not. The best solution I found is a European Mondeo Mk3 which provides 0.1 degrees increments for steering wheel angle to CAN bus at OBD2 - see this post (CAN id 0x201 - I confirm that by trial). – Kozuch Apr 6 '16 at 13:20
  • Have you stumbled on something similar for Honda? – StanTastic Apr 27 '17 at 8:24
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Looking at the reset procedure for the SAS (Steering Angle Sensor) on Ross Tech VCDS wiki here it would appear that within this software measuring blocks 08 groups 007 is returning real-time steering angle data in degrees. Where this data is located other than that I'm afraid I don't know.

The part number for the SAS on VAG cars appears to be 1J0-959-654-J replaced by 1J0-959-654-AG which seems to have been fitted to VW Bora, Audit A3 and Seat Alhambra, Leon and Toledo. I'm unsure of specific models and specs but form what I can see the codes to look for on the boot stick of a vehicle equipped with ESC (and therefore a SAS) appear to be 1AP, 1AS, 1AT and 1AZ.

Hopefully this info is of some help to you. I'm afraid I don't know enough to give you a definitive answer.

  • Thanks for your answer! You made me think of another way of doing the reading - well, the other obvious solution besides reading the data conveniently (in known) format from CAN is to try reverse engineer the SAS itself directly... however, I have close to no experience with low-level electronics hacking, but this may be worth the effort since one only needs to purchase the SAS sensor and not the whole car so the financial risks are much lower... – Kozuch Jun 22 '15 at 10:20
  • @Kozuch same question, how did you end up doing ? I have the same problem, and I'd rather not have to go for a custom solution – Graham Slick Oct 11 '16 at 17:59
  • @GrahamSlick - I went for the European Mondeo Mk3 - see my comment on the question above. The CAN id there is 0x80. VW also has same SAS on multiple models you can reverse engineer it I have no ID for that one. Here is info on the Mondeo - see this post. – Kozuch Oct 11 '16 at 18:06
  • @Kozuch thanks for your answer. Did you also find a way to input steering wheel angle ? – Graham Slick Oct 11 '16 at 19:14
  • What do you mean by "inputting steering angle"? Inputting where? – Kozuch Oct 11 '16 at 19:16

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