Finally have some time to share this project.
Basic idea was to create as “plug and play” solution as possible for autosteer ready CNH machines.
I tryed to use the original wiring harness as much as possible, and it did work great with the steer valve, WAS and pressure sensor. The autosteer engage valve is a little harder but managed to do a little workaround for that.
PCB Kaupoi mod V4
Lenovo Miix 510-12ISK
Chematic for pcb, contains wiring of WAS, orbitrol pressure valve, steer valves and power supply:
And here is the location for dump valve wire at different ecu:
So, for PCB I use Kaupoi mod V4. Ordered the boards from jlcpcb(great service!) and parts from digikey and mouser. Found a maching connector (Case IH Puma 230, autosteer ready - #5 by FiveFinnishFarmers) for the assembly, so it fits to the original harness. I had to add lots of wires to this connector, but thankfully there is lot of free pins.
photo of PCB: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
Pinout for the connector: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
I ran into two problems with the part list Kaupoi has. First the automotive relay was not available at digikey but I found a different more heat resistant version of the same relay: https://www.digikey.fi/product-detail/fi/panasonic-electric-works/CB1-T-P-12V/255-3517-ND/647003
also the BTS442 wasn’t there, so I ended up buying BTS500551(I don’t recomend this): https://www.digikey.fi/product-detail/fi/infineon-technologies/BTS500551TMBAKSA1/BTS500551TMBAKSA1-ND/2051619
Turned out it activates when pin 3 is connected to ground and the pcb has 5V signal for it… so we decided to do a little transistor magig to invert the signal coming from arduino: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
The little DIY board on top is a safety circuit to trigger the remote control with the pressure sensor in orbitrol. It also has a safety relay in series with the BTS. this relay is activated with the autosteer angage switch at rightrear corner of pumas cab.
Here is a photo of the layout: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
Schematic: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
As you can see the steer engage valve(6/2) will be powered only when BTS and relay K1 are powered. K1 gets power from X716 pin3, which comes from that cab safety switch(or does it? more on that later…).
the 5V circuit is for pressure sensing. P is the sensor in orbitrol, R2 is potentiometer for adjustment(2K5 if I remember right), R1 is small resistor for safety and T1 is NPN transitor to trigger remote disengage.
I also did cut the usb cable and soldered the connector pins to get through the same 40 pin connector.
Here is the PCB assembled in the tractor: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
The steer engage valve wire is in different computer and connector, so I had to “steal” that pin. I found that the same pins as in the 40 pin DRC connector works also in this stolen wire, so I just plugged an extension wire to the original stolen wire and wired that to my PCB.
photo of the connection: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
I bought an assembly tool for DRC pin removal from digikey, I really do recommend this as otherwise pin removal is extremely hard.
Wiring of the original WAS needed one modification to get it working. The original harness goes from navcontroller(pcb location) to right side of motor cooler where there is a connector that has an end plug on it. Very close this is similar connetror that is connected to different harness, this is the line that goes from orginal WAS to ECU, CNH uses WAS signal with automatic front diff lock. Normally in the factory when autosteer is installed they switch the wire coming from WAS to the other plugged connector at the steer ready harness. From there the signal goes directly to navcontroller(X716) and maybe the navcontroller sends WAS value forwoard via canbus… So I had to make a litle Y-devider for WAS wire to get the signal to go both ways, to steer ready harness and to ECU for diff lock. The connectors are once again pain to find and it turned out to be an old ford connector. I found set of these connectors: Case IH Puma 230, autosteer ready - #30 by FiveFinnishFarmers
I powered the WAS with pcb trough steer ready harness to get stable signal and jumped only the signal wire to go both ways, so the ECU is never powering the was, it only gets the signal.
Photos: Case IH Puma 230, autosteer ready - #32 by FiveFinnishFarmers
AUTO STEER CONFIGURATION
It turned out to be a tricky valve to find good settings. I did have a lot of “drunken driver” style slow waving from side to side. To me pure pursuit works better. Here is the setting when driven for one season. Maybe a little bit longer look ahead and little less integral would be good change to this setup.
WAS Zero: -2.33
Counts per degree: 191
Max steer angle: 15 (with dual tyres)
Overshoot reduction: 1
Look ahead: 3.4
Look ahead speed gain: 1.8
Side hill deg per deg of roll: 0.11
There isn’t many problems that occurred during installation. In fact, the assembly did go almost exactly like I planned it. Only thing that surprised me was the absence of one contact in cabin safety switch( S-005 in schematic).
As I told earlier I planned to power my safety relay from X716:6 which comes from S-005 first contact. It turns out that although the wiring harness goes exactly like in diagram the S-005 doesn’t have that contact at all unlike what the diagram shows. To get the voltage for my safety relay through that S-005 I had to use its second contact which feeds the other drc connector called X720 and it’s pin 3.
I decided to steal pin X720:3 and move it to X716:6 to get my circuit working.
As I’v now talked with other members here, turns out this absence of the contact is quite common.
Not the best solution, but it works: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
I also did run into weird problems with CMPS14 being inside the enclosure. the imu/compass would do weird things once in a while. The roll did work great all the time. In the end I decided to remove the cmps from pcb and use seperate arduino/cmp comdo mounted near the sky window, this seemed to get rid off any interference.
here is STL and OBJ files for every part that I printed for this project.: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
For PCB enclosure there is an endplate that has mount for DRC connector. Also a plate and clamp for mounting the enclosure to same place where original navcontroller would go(under the storage “cup” behid passenger seat.). The mount for enclosure is oriented to face forward, so CMPS can be mounted to the pcb(allthrought I ended up to use seperate arduino and cmps located near sky window to avoid interferences). There is also a little thing that I used to screw my pcb in place inside enclousure. I just glued this thing to enclosure and it has a hole for screw.
There is also a tablet holder that can be installed to armrest. It goes to the same place where genue intelliview would go and has inserts for M8 bolts and nuts. It has an odd sliding mount for easy tablet removal. I did use double sided tape to stick the slide plate to backside of tablet. This same slide connector fits also to genue intelliview holder, if someone happen to have a spare holder without intelliview Photo of the holder: Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
I did use PETG for my prints, but I do not recomend this as my prints are deformed in heat. ABS or other more heat resistant material would be better in tablet holder. The enclosure holder is bearly strong enough with PETG.
I’ll edit more info later(part numbers etc.)… just don’t have more time today.
Here is a little first test drive video:Microsoft OneDrive - Access files anywhere. Create docs with free Office Online.
EDIT: Filled little more info. 16.6.2021
Added chematics, link to pin assembly tool and problems section 27.8.2021
Added printed parts and a CMPS problem 23.9.2021
Added tablet model and auto steer settings 2.10.2021