The hardware is built around a stackable 10×10cm compute module with two ARM Cortex-A55 SBCs — one for ROS 2 navigation/EKF localisation, one dedicated to vision/YOLO inference — connected via a single ethernet cable.

I will preface this by saying that I have nothing against ARM per se, that my employer/team supported a good chunk of the work for making ROS 2 actually work on arm64, and that there is some good hardware out there.

I really don't understand why startups and research projects keep using weird ARM SBCs for their robots. The best of these SBCs is still vastly shittier in terms of software support and stability than any random Chinese Intel ADL-N box. The only reasons to use (weird) ARM SBCs in robots are that either (1) you are using a Jetson for Jetson things (i.e. Nvidia libraries), or (2) you have a product which requires serious cost optimization to be produced at a large scale. Otherwise you are just committing yourselves and your users/customers to a future of terrible-to-nonexistent support and adding significantly to the amount of work you need to bring up the new system and port existing tools to it.

I also notice you're using the BNO055 -- if you need an C++ I2C ROS driver for it I wrote one (https://github.com/dheera/ros-imu-bno055). I think the one in the ROS apt-get repository is written in Python but they claimed the package name before I did

One leading contender is SwarmFarm Robotics, based out of Queensland.

* https://advance.qld.gov.au/innovation-in-queensland/innovati...

* https://www.swarmfarm.com/

For interest, here's a recent opinion / demonstration from an unassociated Australian farmer considering a purchase.

The farm is Tom’s Brook, a grain farm located in Esperance in Western Australia. It’s a family operated business growing a mixture of Wheat, Barley and Canola on 4500 hectares (11 200 Acres). Sizewise is pretty much bang on the average W.Australian grain acerage.

Seeing a Swarm Bot in Action (20 min) - https://www.youtube.com/watch?v=ljEKN7CsjnM

The unit pair in action here, autonomous tractor pulling intelligent boom spray, has had 10,000 acres of operation prior to this customer demonstration.

Unloaded weight ~ 3.5 metric tonne, loaded approx 5 tonne.

Runs at about 13 hectares per hour, max speed 10 km/hour.

Advantages of "intelligence" during operation are reduced spray usage (basic green on dirt detection, and green shape on mixed green patterns) and weather patience (happy to sit idle until wind and humidity are optimal)

70 odd Comments include feedback from other farmers already using such agribots, eg:

  Just rolled over 12,000 hrs on our swarmbot.  4 years, 3000hr a year, doesn't get into the shed much.

--

[1] Robot Sheep Shearing (1985) https://www.youtube.com/watch?v=6ZAh2zv7TMM

Has any stress analysis been done on the frame? Looks to me like it could use a couple more triangles to reinforce those rectangles.

Have you designed a skid-steering controller for it? Off-road skid steering can be quite variable obviously depending on terrain properties.

[1] https://github.com/NVIDIA-ISAAC-ROS/greenwave_monitor

Recommend going to a farm right now to see how this works in production. For the most part, you can autonomously sow using GPS. But the farmer just rides along.

https://www.opensourceecology.org/

It would be nice to see some temperatures in relevant points, when the computer is stress tested in the closed waterproof case and a hot ambient.

The Cortex-A55 based CPU has low power consumption, but it is not negligible and without a heatsink it may overheat and throttle.

Moreover, in a closed box, one may need some means to transfer the heat from the stacked electronics to the aluminum walls of the box. Finding suitable means may be more complex for this design, because of the curious choice of using 2 weak SBCs instead of 1 good SBC, so there are 2 sets of CPU + memories that must be cooled.

From the provided pictures, I cannot see how the electronics would be cooled well enough, especially when working outdoors during a hot day.

Nevertheless, the initiative looks cool!

or some automated green house with open source designs.

love the name sowbot.