What in the actual? The Hacksmith has turned out their biggest ever build, and we were thrilled to learn that it’s running on Revolution Pi – an industrial device with a Raspberry Pi at its heart. This giant ride-on spider robot was a proper mission, taking up a year and a half of its maker’s life. It’s technically a robot hexapod, but it looks like a cool spider to us. Its proper name is MEGAHEX, just like that, all caps.
The Hacksmith was inspired by a video of an auto excavator manoeuvring its own body by using its excavation arm as a leg. An idea struck: why not just bring six excavators together and program all the arms to operate like legs in sync?
Design hell
Solidworks design software allowed for hypothetical stress testing of the hexagonal frame, but in real life, once you start sawing up steel frames, it never quite matches up to your beautifully rendered model. The Hacksmith had to cut parts up and re-weld them multiple times. Instead of the two days originally planned, this part of the project took over a week to complete.
Auto excavator buckets proved to make unstable feet for MEGAHEX, so the maker replaced them with flat steel octagonal plates. In my opinion, the buckets would have lent a cool spider-on-rollerskates vibe, but I can see how MEGAHEX’s pilot might not feel particularly safe perched above them.
Single pilot control with Raspberry Pi
Without the computerised control system, this giant spider would need multiple pilots, one for each leg. That would add lots of weight to an already stressed frame.
Instead, a single pilot steers the mechanical beast. An onboard Linux computer is responsible for calculating the position each individual leg needs to move to, based on the pilot’s input. That data is sent to a Revolution Pi, which is responsible for working out how the legs are currently positioned using sensor data, calculating how they need to move in order to get to the new positions, and sending the commands to carry out these movements.
Learn more about MEGAHEX
Dive in to the wonderfully comprehensive build video to learn more about the making of MEGAHEX. You can watch all the way from the scrapped early designs for the frame shape, through to human stress testing, and finally a car park full of astonished YouTubers watching MEGAHEX take its first public steps.
