Vineyard tractor guide without GPS

Projects Project ideas - in progress
1

Hello,

I’m looking to make a feeler guidance system (without GPS), just to stay in line without touching the steering wheel.
For the material, I will go on an 2 feeler at the font +arduino + electric motor on the steering wheel + steering angle sensor as for the AgOpenGps system that I already have on another tractor.
However, I need help with the arduino code, as there is no tablet or guidance software.

Does anyone have an idea?

I can’t find anything on the internet anymore and yet when I was on the project for the first tractor, I came across a post that talked about a homemade feeler system.

2

How do the feelers work, mechanically?

3

yes mechanically, with a contactor (on/off) on each side

4

But how do they work, specifically? What are they feeling? A furrow in the dirt? Tree trunks? At what speed does the tractor operate?

5

What about this setup:
One steering motor
One Cytron motor controller
One voltage regulator (0 to 5 V) (or potentiometer to regulate PWM in on Cytron)
Maybe it is best to have optocouplers between your 2 on/off switches and the input of cytron (to protect cytron from switch noise)
No arduino.
The switches either make DIR on cytron low or high (left or right)
Voltage regulator on PWM adjust how fast motor should turn steering wheel.
To prohibit a short between high and low you must connect NC and NO on both switches so if one is ON the other switch can´t get on.
If your “feeler” system can´t reach both sides you can add a spring that forses the “feeler” to one side.
Edit: if your contactor does not have both Normally Open and Normally Closed, you could add 2 relays that have both.

6

They feel the vines plants. The tractor operate between1 and 5 km/h

7

That can be a good Idee.
But what does the Cytron do if both contactors are off?
The tractor wheels should be straight when no switch is actuated.
That’s why I wanted to use an arduino with a steering angle sensor.

8

Aaah I forgot that, it will always do one way.
But IBT_2 can do it, (or a Cytron with double motor driver) Now you must turn on/off the PWM for each side( at whatever amount you have set your PWM voltage at) NEVER allow both pwm at same time!
Here is an Arduino excample if you can use that instead.
https://www.google.com/search?q=ibt_2+pinout&sxsrf=ALeKk01gr0AYOJkBNHyLkTnxqvW1B6NWmQ:1597137187182&tbm=isch&source=iu&ictx=1&fir=qP2zLMAEen-gqM%252CuJO6XM3re521uM%252C_&vet=1&usg=AI4_-kR8vbuxBabU1rPKMeIg-yAkl9r4dg&sa=X&ved=2ahUKEwjRgMzV55LrAhWFqqQKHQk1AB4Q9QEwAnoECAoQCA&biw=1450&bih=706#imgrc=qP2zLMAEen-gqM

9

I think instead of on / off sensors
2 left and right potentiometers connected in series + steering sensor and pwm value calculated on the basis of the error similar to ino AgO.

10

is there any update in this project?