Hi everyone. I have been experimenting with building something similar to Acorn with 50% size for a while now. I used a ardupilot flight controller (pixhawk) and configured it for navigating a skid steer vehicle like this. In addition I used ardusimple GPS sensor with RTK and a motor controller from Cytron. Everything is currently build with aluminium profile bars - which is very nice for fast prototyping. I plan to build it a little bigger as soon as the rest is working as expected. I am a bit focused on market garding with only 80cm bed-width - so I will not build it much wider than that.
Currently I am working on making the drivetrain more durable.
Afterwards I am thinking of adding some weeding tools inspired by Romi ( The Rover for Weeding | ROMI: Robotics for Microfarms. )
It is currently not close to the durability of Acorn but still it has some similarities and I thought it might be interesting for people to see. I also plan to publish it open source as soon as I have a design is more or less finalized.