it look like the problem came from the usb hub
when the gps signal is gone (not coneted) the system don’t respond anymore so all test i did fale only when you place agopen in simulation mode the signales from the arduino go true without a gps conected
tomorow i gona buy a replacement to be sure that was the real problem
ok it work now
the problem was the usb conection
use contact cleaner and al work again sometimes i have still a disconection that remain after a few seconds maybe there is still an bad contack in the usb conectors there are to many conections arduino/ardusimple to the usb-swith an extention cable 1.8 m a transfercable .2 m usb A to micro-usb it would be beter to do it in on cable
Which .ino are you using in the Arduino?
And which version of Agopen on the computer?
If the GPS signal is lost in the FJ Dyna system, is the vehicle’s ability to keep going straight for 20 minutes thanks to the IMU, as Alan Webb did?
i use agopen 5.2.1 with the .ino from this version
as tablet i use medion akoya md99400 it work but not powerfull enough a faster one would be better
today i will adjust the steer settings
and than the settings for the field where i don’t find a good guidance youtube movie
i like just drive around the field to know what are the dimentions and than lines at the same distance back and fort (harrowing 3m)
iemand van vlaanderen of nederland hier die me wegwijs kan maken hoe te gebruiken steeds welkom
when you use a bno085 as 9 axis sensor be carefull follow the specs it work on 3.3 v not 5v there is a 3.3 v output on the arduino you can use this pin to power the bno085 (the bno085 survive 5v but i don’t know for howlong)
I very much doubt it would go at all without GPS signal. What the FJ system will do is go for 20 ish minutes without a correction signal as long as it has had one to start with. It won’t work at all if there isn’t a correction signal to start with.
My IMU steer thing was actually using the IMU to provide a WAS value instead of using an angle sensor.
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i have both a was sensor and a bno085
Did anyone tried to use imu sensor on wheel?To measure angle?
why will you do that ? a was sensor will mesure that what you need the pure angle of the wheel
Becouse there are no moving parts.
Easy mount
you will need 2 imu and compare them to get the wheel angle maybe that work i haven’t try
it will never had the same acuratie like a real was sensor
If you are going to rely on an inexpensive IMU for steer angle you might as well use rotational velocity as in the totally WAS less thing I was trying. Comparing two inexpensive IMU’s ( or even worse one IMU and a calculated heading) and hoping to get anything accurate enough for a true WAS reading sounds like a minefield to me!
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Alan, would you know a minimum reliable imu to have a wasless system?
You have to regard the combination of IMU and GNSS. Any micromechanical IMU (those we’re talking about here) can only detect accelerations - it has no absolute orientation. And that leads to drift, which has to be adjusted with the GNSS data.
That’s no rocket science, but we would need several people with different vehicles to do tests like Alan. He just modified the Nano code, which has to fail, when the IMU is drifting, just because the Nano has no change to compensate that. Nevertheless working not too bad and a perfect proof of concept. 
Generally, I would see an Arduino RP2040 Connect board there, having an Ardusimple connected to it as well. This would be motor control, GNSS and IMU in one.
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Trimble has been using a single gyro to measure steering angle for years. It does not work unless you’re moving. I’m not sure the math behind it.
I think using a POT and a mechanical linkage is much easier and more robust. In fact sometimes on my sprayer I wish I could replace the gyro with a simple POT. I may change it some day.
Would a teensy 4.1 with the standard imu, gps and ‘the panda approach’ minimise that drift for having good wasless capabilities?
it’s not a matter of calculation power. it’s more like finding the best universal approach. We’re talking about navigation and not about bitcoins mining $$$$… 
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One advantage I found with the IMU steer angle thing is it compensated for side draught and slip really well.
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Quick question… the above .ino file says for version 5 anyone using it with the latest stable release? (5.5.0)
Not a truly WAS-less system as mentioned above but a work in progress solution with an encoder. The hardware used is basically everything you need for a Cerea setup (after all I bought a Phidgets “Cerea kit”). This includes the Phidgets 3269 DC Motor, 1065 PhidgetMotorControl and 3531 HKT22 rotary encoder.
The idea remains the same: use the encoder as a WAS. There are no modifications necessary to AGOpenGPS nor the GPS system (I use a Panda board for now). Additionally, there is no need for a PCB like AutoSteer, KaupoiMOD or motor driver since the motor and encoder are controlled by the Phidgets motor controller.
The main contribution is a Python program running on the tablet. It looks like a steering controller with WAS to AGIO because it implements the UDP interface. The communication with the Phidgets motor controller is done using their SDK and a USB connection.
The idea and code are inspired by other referenced projects. You can have a look here: GitHub - ScholliYT/agopengps-phidgets-steering: Steering system for AgOpenGPS using the Phidgets DC Motor Controller with an Encoder
ToDo:
- Testing outside
- 0 point tracking (as discussed here I will probably go with the IMU idea)
- GUI
In the future I hope this helps people coming from Cerea or starting from the very beginning to test AGOpenGPS without the need to install a real WAS.
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