power steering hacking

bump

did you ever finisch your project TS?

 

I'm surprised nobody has posted a link to the automated robotic Prius that was given an opportunity to be tested on the streets of San Francisco several months ago. I remember it was taking a lot of criticism from the photo seen in this article because the back wheel is on the center stripe in the road:
Robotic Prius takes itself for a spin around SF | Cutting Edge - CNET News

But there was speculation as to whether it could have been completing a turn or some other situation that caused it to be over the line. Who knows...

 

Here is how IPA works and what components you need:

http://priuschat.com/forums/gen-ii-...elligent-parking-assist-ipa-2.html#post888384

If someone installs it, please let me know..:rockon:

 

ghost ride your whip

 

Havent read the whole thread yet (getting there), but if this is correct, then great find! I am working on a custom AFS system and my last hurdle is getting the electronic steering position from the car.

 

Now I see there is a CAN interface for the steering too, that seems like a more "modularized" way.

Is there a known colour code combo for internal module CAN connections? Meaning I dont want to tap into the J1962 connector, but rather into the wires inside the dash that the various modules actually use. Is there a detailed wiring schematic of the Prius somewhere online?

 

When torque sensors fail (and Prius ones do) the steering wheel shudders violently and rapidly until you shut the thing off. Hopefully, by that stage, your Prius isn't heading for a tree or another car in the opposite lane...or a young child on the footpath.

 

Good point; it matters what generation Prius you want to hack on. Gen 1 used simple potentiometers as torque sensors, and they would indeed get noisy with age and lead to the behavior described. Gen 2 ditched those in favor of non-contact, magnetic sensors, which have been used ever since.

-Chap

 

This can’t really happen on gen 2 Prius as the torque sensor is hall-effect. Potentiometer type sensors (in other cars) can wear to the point (or fail in a way) that it causes a bit of shaking in the steering but car is still easily steerable.

 

People's reported experiences in the Gen 1 (which used potentiometers) were all over the map. Mine did a bit of shaking which was never a big deal as long as I had two hands gripping the wheel. (Didn't have to be a white-knuckle death grip either; just a normal grip. All that mattered was having the extra mass of two arms hanging on the wheel to dampen the motion.) The shaking would die out in half a second or so. If it started oscillating and I let go, it could do a sustained oscillation that got violent, and that was the behavior a lot of people reported, maybe because their first reaction was to let go.

After enough miles of that, the steering computer would say "all right, bogus torques for long enough" and switch off the assist, and I'd be driving around a manual-steering Gen 1 until the next ignition power cycle. (That was good upper-body work, as the car is heavy in front, and the gearing was chosen with power-assist in mind.)

At least one person reported the steering just turning at full power to full lock at one side. Never happened to me personally (and I'm not sure why the steering computer would believe such an obviously extreme torque input, as I can hardly imagine the two independent potentiometers agreed on it), but it would sure be distressing if it happened.

-Chap