the motor
You have 2 choices here: 24V or 12V
If you're going down the steering-wheel-motor route, the Phidgets is the one to buy. There are alternatives, but PotatoFarmer has made an excellent 3D-printed holder that fits it nicely (see below)
Specs: 24V 600RPM 5.1kgcm torque
https://www.phidgets.com/?tier=3&catid=19&pcid=16&prodid=993
Note that if you're using a 24V motor as above, you'll need a 12V-24V step-up converter, sample here.
https://www.ebay.co.uk/itm/334688323208
This is mostly used by the French guys you can source it from a couple places in europe. You can get roughly a 30% discount from the manufacturer when directly ordering from them but you need to order 5+. https://www.mfacomodrills.com/gearboxes/986d_series.html
Specs: 4:1 ratio 12V 1300RPM 3.3kgcm
(you can likely add an extra 10% as the tractors voltage is around 13-14V) which makes this less powerful than phidgets but good enough for U-Turn
Make sure the v2 AIO board has extra traces as this can easily eat 5-7 amperes at peak.
https://www.aliexpress.com/item/1005001644698564.html 5.2 :1 ratio 12V 950RPM
We've seen all kind of 12V motors being used from drills to Opel Corsa C electric servo. Choice is yours.
For some ideas on how to mount the motor to the wheel, check these resources out: https://discourse.agopengps.com/c/hardware/stl-file-links-and-bracket-ideas/39
PotatoFarmer has made an awesome 3D printed gearset and motor holder, check that out here: https://discourse.agopengps.com/t/universal-fit-gear-system-with-quick-tach-motor-holder/6579 STL for the MFA motors small gear: (don't use PLA for it go with PETG or TPU) https://discourse.agopengps.com/t/universal-fit-gear-system-with-quick-tach-motor-holder/6579/269
If you prefer steel then check out bricbric -s design here: https://cults3d.com/en/users/entropiemaximun/creations
- If you don't have a bender: https://cults3d.com/en/3d-model/tool/universal-clutch
- If you have a bender: https://cults3d.com/en/3d-model/tool/universal-clutch-v2-bending-steel Forum post: https://discourse.agopengps.com/t/small-teeth-and-friction-universal-mecanism/9669
There's a useful MF 76-77 mount here: https://www.thingiverse.com/thing:5427025
Use at least 0.75mm2 wires. You'll have a hard time putting a 1.5mm2 into the Ampseal connector. So likely 1mm2 is good enough. Which wire goes where?! You can invert the direction from AgOpenGPS so don't worry about it. V4 board can easily handle the 12V motors without extra traces. Use Pin18 on the ampseal as that's a direct connection to cytron. Add a 10A fuse before it.
When the motor is not used it acts as a resistance. When the cytron is connected it acts like a brake. You have a few options. Playing with electronics is risky so do it at your own risk.
Bricbrics holder can physically detach the motor.
Get a proper relay such as: Bosch 0332019110 Use the Lock pin which is a switched 12V output to trigger it. Disconnect one of your motor wires.
This new AiO board has the option of connecting pwm2 to the cytron for the freewheeling mod.
