Grass is a lovely thing to have, but unfortunately it tends to grow excessively long if left unattended. Obviously, one can use a regular lawn mower, but [Daniel] of [rctestflight] decided to build something remote-control instead. (Video, embedded below.)
To get started, [Daniel] fitted X-acto blades to a brushless outrunner motor, and tested their ability to cut grass. Satisfied with the performance, he built a trailer to tow behind an RC tank mounted to such a setup, with some success. With the concept beginning to bear fruit, he went with a clean sheet design for maximum performance.
The final build relies on an RC rock-crawler chassis, fitted with a brushless motor using field oriented control for maximum torque at low speeds. This allows the RC mower to slowly push through the grass without overwhelming the cutter heads. As for the cutter heads, the final rig has eight motors, each sporting two blades to chop down long field grasses with impunity.
[Daniel] notes that it’s remarkably fun to cut the grass in this way, and is surprised not to have seen more builds in this area. (Editor’s note: he needs to read more Hackaday.) Of course, we’ve seen plenty of autonomous builds, too.