Frag mal auf telegram wegen der Kupplung - gibt es schon…
Nice work, very well documented
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Firstly, great documentation! this will help a lot of people take there first steps into AOG.
I have a similar setup to you at the moment, with a 3d printed cog to the steering wheel.
To make the steering wheel turn easier when it is connected to the motor, have you tried adding a relay to to cut the power to the motor?
The trigger for the relay comes from pwm2 on PCB autosteer board.
This has made my steering wheel very easy to turn, even with the cogs connected.
Hello,
Andreas suggested that before, I tried it while the board was not powered and it was still very hard to turn. Will have to try disconnecting the motor completely, I am not sure if I did that. If it works, id like to add something like Juliennorth build: Autosteer disengagement (torque measurement)
This way I wouldnt have to press a button or anything like this
Merry Christmas btw 
Update: Tested it today and it turns really easy when disconnected! Think I misunderstood Andreas a bit, now I’ll have to build the disengagement
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Thanks for bringing Autosteer disengagement (torque measurement) to my attention… just bought all the bits to try and add this feature. Will make turns on the headland/ obstacle avoidance much easier!
Merry Christmas to you also!
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Finished my assembly today, based on the short test I did it works great!
I modified the code quite a bit and got a (as I think) little simpler solution. I still want to change the way the amperage is interpreted by the code to get the full range of the potentiometer for fine tuning, since the ADS712 outputs around 2.5V with no spinning motor and values above that when really measuring current. I in fact assume that the input voltage to the cytron is constant, so the power drawn is directly proportional to the drawn current. So I simply compare the measure value of the potentiometer to the value of the ammeter, not dealing with real values. That way I dont need to measure the voltage. I also have no LCD, so no code for that.
I use the 2 channel relay to act as a steering switch and to break the circuit between cytron and motor when autosteer is disabled.
Test_Disengage.ino (620 Bytes)
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great job for electric sterring wheel
as idea,
why not to integrate this in “autosteer.ino”
for analog value
A0 A1 looks free on PCB V2
or WAS Aux 1 and Aux2 are also free
for numeric output with cytron board
Cytron Pwm2 is ready to cut off the signal
after need to make rules with “pwmDrive” value and the potentiometer or software value
need to simulate this data to understand more the relation of this ADS712 and Pwmdrive
I think it is already made. output from ads712 instead of the pressure transducer
Or simply.
Ads712, potentiometer and transistor on the remote, like Tervuren made it.
And then let led_enable pin (dir or pwm2) control the cut of relay to motor
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I tried to add machine control to my setup, I thought I could just use a relay to act as a switch to trigger the three point hitch. Problem is that my tractor has a potentiometer that does the switching, I dont know how to deal with that. Anyone an idea?
Which tractor is it? Usually the potentiometer is there to set the working level but a three state switch selects the work position/neutral/raised position.
Its a Claas Ares 816RZ. I also thought it should be a three state switch, but to me it looks like a potentiometer…
In the manual that switch is called “5-position mode switch (transport, high position, stop, working position ans dropping)”. If I hold down the switch to dropping, I do measure a fourth value for resistance, so it has at least four positions.
The best solution would be a tile for I2c. It just takes someone smart to write code for it. I have a similar switching method in my MF5455, there is a switch but it changes the resistance to several levels and it cannot be turned into an on / off switch.
It is possible to switch between the set of resistors
Did you measure the resistance figures with the switch connector detached?
You could do like baraki suggests or you could just use a relay to alternate between raise an lowered positions (if that is what you need). In either case I’m afraid you would need to build a master switch that swaps between the tractor switch and AOG control. A bit complicated to operate if manual override is needed in emergency or other scenarios.
It could be a sort of fault detection, if the resistances vary from the preset the control unit realizes that something is not working and can provide an error code.
Did you measure the potentiometer with the 3 pin plug disconnected from PCB?
Disconnecting changes the resistance, but it still looks like a potentiometer, a 5K.
I could just use a relay to switch between the original switch and the digital potentiometer. To detect when I use the original switch some kind of encoder might be useful. That way the arduino would automatically do the switching. So to use machine control, the original switch has to be at neutral position, when its moved away machine control gets deactivated and has to be enabled manually in AgOpenGPS again.
The Arduino could measure the voltage on the potentiometer (green wire) and the switch to manual control could be detected. In automatic mode it is enough to increase / decrease the resistance for lifting / lowering added in series with the green cable. It should work.
So you mean I set the manual switch to low position and kind of add the needed resistance to get it to raise? And when the voltage changes by manual switching, the arduino knows that because it did nothing to change voltage? When I connect the digital potentiometer in series, it needs to have a resistance of 0 ohms when not powered to make everything work normal without automatic control.
Just like that!
To achieve 0 ohms for manual control it is possible to put an NC contact relay in parallel with the digital potentiometer.
edit
Now I think it can be simplified even more because the ECU probably measures only voltage anyway, so the digital potentiometer is enough if it adds V to the green cable, adding a diode would allow you to still measure the voltage on the tractor potentiometer.