A while ago I implemented AgOpenGPS on an open station New Holland TT75. Since then I took the next step to implementing autosteer and am happy to say it’s been pretty successful. With a few hundred successful U-turns now completed I am very happy with its performance. Thanks to everyone involved. I’m happy to post details if people would like them.
A couple of notes on things I’m encountered unique to a no-cab environment and where I live.
Heat - I was worried about how the heat would affect electronics. So far no problems except perhaps with the motor. Hottest day so far was 38 deg C so not ridiculously hot this summer but still consistently working in hot, sunny conditions. I mention the motor which was very hot to touch, but I realised that everything else was as well, i.e. the black plastic trim next to it was too hot to touch as well being in direct sun. The next day I had intermittent problems with the motor which I tracked down to the brushes, so I think it’s going to be pretty hard on the motor in general.
Dust - dust is diabolical. The electronics box is sealed, but it will be interesting to see how the tablet handles it over time, and it is likely to be a problem for the motor as well. I was looking at the WAS as well thinking it may well wear out pretty quickly as well. It may have been better mount it upside down.
Traction on steer wheel - I have a rubber wheel that I pinched off my sons RC Touring Car mounted on the motor. It was very grippy and ideal, but after being hot baked it suddenly became hard and wouldn’t grip any more. I put more tension on it but it was still slippy and too much force on the motor is good for the motor or the tyre. A trick I learnt from my sons brief RC racing career is that WD40 make a good tyre “sauce”. Clean the wheel and soak it the day before and it comes good again.
Canopy Vibration - I have the GPS receiver up on the canopy but it shakes pretty violently. I think that restrict precision a bit but it pretty resilient to it otherwise. I may try mounting it on the bonnet of the tractor and see if it makes any difference.
Otherwise the only issues I’ve had have been related to IMU stability. It struggles a bit with narrow implements and tight uturns, so use skips in that case, but the more recent revisions might fix those uturn anomolies.
Dear potato farmer, I have read so many documents that I am very confused, 100 cm. For my track-width vehicle, should I use my antenna in front of the hood or above the rear axle? If the front of the car is better, Stanley or Pure Pursuit?
I am using pure pursuit and have it in front of the front axle without issue and works extremely well. The tractor I use to play with AOG is quite small, but the errors it makes are quite small as well.
Also the tractor ends up in over hanging treed situations from time to time that may damage the helical antenna, So low on the front hood makes sense for that too.
But I think the best answer is you want to locate it a spot where the antenna will pick up more or most offline movement. The higher the resolution of the error, the more tuneable the control will be. The software will calculate where its ideal position reference is based off the machine measurements entered anyway.
The main reason top of cab became so popular was the poor reception and poor performance of the original gps only waas units.
Yes, in my tests today, pure is more successful, as you said, I will take the antenna further and try again, thank you for your support.(I accidentally uploaded a stanley video instead of Pure, but pure was better.)