EPS Electric power steering

Started by 65fpvmustang, February 29, 2016, 07:36:51 PM

65fpvmustang


65fpvmustang

i ordered 1 off eBay wife's going to kill me.lol

punisher454

 I have a strong suspicion that the "Kit" that guy is selling on ebay is just either just a pot, or its a PWM output variable through a pot. Something you should be able to do way better (like add vehicle speed input) with a cheap uC like an arduino (even a $5.00 arduino mini or nano clone).

Those particular steering units come on a couple years of Saturn's. Be aware that there are two or three different units that came on the same cars, but only one has the good control box that you can use.


Rx7man

Mazda Rx8's had electric power steering as well.. don't know how they worked though
'94 dually,  67/67 HE351VE, NV5600, ~600hp
'93 ECLB 47RH, new toy truck, H pump project, 1000hp goal, 300K miles
93 XCLB auto, bone stock, 350K miles
93 XCLB 5spd, bone stock, 100K miles

65fpvmustang

the control was only 60 so I ordered it to play with comes with pot for control.
I looked under my dash and watched a mustang plus video for there $1500 eps looks almost identical. down to the $60 ebay control.

65fpvmustang

#5
After more research the toyota prius and rav4 ar can bus controlled.
http://www.toymods.org.au/forums/threads/79652-Electric-power-steering
Quotechange the setting to 500kps to match the network speed of the can system. Then back to the tab "can transmit". Now has i said earlier the hex for rpm is 2C4. The data length is 11 bit. The dlc is 8. The information i used was ramdomly picked after much trial and error. Almost 3 pages of codes I tried. I could set a rpm in connect my scan tool and see the rpm but still now assist. After much frustration i finally realised that it was a setting i had wrong. It was how often i had it repetting the message. The end result looked something like this 2C4 8 06 8A 00 19 00 00 92 09 Repet rate 20 ms(milliseconds) . All this done and turned the car on and immediate assist. I still have not been able to drive the car and see if it feels bettter. Still working on some idle issues with the engine. I could however tell the assist was greater. Last thing to work on is connecting the can wiring to the dlc so i can see about changing the setting for the assist level at idle.

65fpvmustang

so 500kbs can bus good for megasquirt bad for lil blackbox

Rx7man

I've been toying with the idea of removing pretty much all the calculation code from the LilBB and just having it transfer the raw inputs to the R-pi, having it do all the grunt work and math, and then sending back the new positiong... Of course this will rely on good communication between the two units, and perhaps require some backup on the arduino so you don't lose all turbo function in case of a bad connection.
'94 dually,  67/67 HE351VE, NV5600, ~600hp
'93 ECLB 47RH, new toy truck, H pump project, 1000hp goal, 300K miles
93 XCLB auto, bone stock, 350K miles
93 XCLB 5spd, bone stock, 100K miles

65fpvmustang

#8
wasn't knocking lil black just can't do both can bus speeds at same time.
Ahh but you were probably thinking 2 lilb with one pie.

I'll probably sand my welds down and paint the actuator to hide them.
I work with a very cocky welder and don't want to hear about them. ::)

hakcenter

I don't think it's possible to have multiple bus's.

If you stacked units, you might get away with 1 on 1 channel, another on another channel, by stacking shields... and moving the CS pin for the second shield to another pin say.. pin 9, and CAN2(9) in your arduino code.

I imagine that would work. Waste to do my shield twice though, use a seeed canbus shield.
TS2009 Deḇarim 8:2
"And you shall remember that יהוה your Elohim led you all the way these forty years in the wilderness, to humble you, prove you, to know what is in your heart, whether you guard His commands or not.

Rx7man

Get a processor that has 2x Can interfaces on it already and design the whole board :P
'94 dually,  67/67 HE351VE, NV5600, ~600hp
'93 ECLB 47RH, new toy truck, H pump project, 1000hp goal, 300K miles
93 XCLB auto, bone stock, 350K miles
93 XCLB 5spd, bone stock, 100K miles

65fpvmustang

Corsa epas  http://www.super7thheaven.co.uk/blog/corsa-c-epas-speed-controller/
QuoteCorsa C EPAS wiring

The column has has two connectors that need inputs:

A power connector with 2 thick wires
Red – 6mm2    +12v ignition permanent positive (50amp fuse needed)
Brown – 6mm2    Earth

A signal connector with 5 thin wires
Blue / Red trace – 0.5mm2    Speed Sensor (ABS) Input
Red / White trace -0.5mm2    Engine Multi-Timer Input
Black – 0.5mm2    +12v Ignition switched positive
(5 amp fuse)
Green – 0.5mm2    Engine rpm Input minimum 55Hz maximum 30KHz
Brown / White trace – 0.5mm2    Diagnostic output

When you apply just power alone to the Corsa EPAS column; via the 2 thick Red and Brown wires; it does absolutely nothing as it is expecting rpm and speed inputs.

The first thing I found, was that you have to apply a square wave signal to the thin green wire. This signal needs to be minimum 0 – 5V peak to peak and an absolute minimum of 55Hz (read on). Without it the column does nothing.

I had one of the those cheap control boxes you buy off fleebay for testing purposes. They're simply a little square wave oscillator with the frequency adjusted by a small dial or potentiometer (probably built around a 555 timer). These very simplistic units apply identical square waves to the green and blue wires. It doesn't make any sense to me to put identical frequency signals onto the RPM and Speed inputs, surely that's going to mess with the Corsa's EPAS assistance maps.

Rx7man

That guy has quite a project going
'94 dually,  67/67 HE351VE, NV5600, ~600hp
'93 ECLB 47RH, new toy truck, H pump project, 1000hp goal, 300K miles
93 XCLB auto, bone stock, 350K miles
93 XCLB 5spd, bone stock, 100K miles

Rx7man

The worst car I ever drove was a Saturn Ion.. this was a brand spanking new car, about 2007 at the time, 3000 miles on it.. you COULDN'T take your eyes off the road for an instant or the car was darting off into the ditch or oncoming traffic, it was seriously scary... My favorite no-frills car was the Pontiac G6.
'94 dually,  67/67 HE351VE, NV5600, ~600hp
'93 ECLB 47RH, new toy truck, H pump project, 1000hp goal, 300K miles
93 XCLB auto, bone stock, 350K miles
93 XCLB 5spd, bone stock, 100K miles

65fpvmustang