Bone Dead Robotics

The April event is the 2nd NHRL event of the year which puts it historically in a very difficult position. Over the past two years, a pattern has emerged where the March event of the year is met with a 2nd place finish by the flagship machine (Phenomenon in 2023, Vorion in 2024) which retires it for an event cycle and leaves the heavy lifting to the other machines on the team. Last year this meant that Fracas and Demogorgon were called in but they had terrible results. This year it was Mind Flayer’s turn and this event was not going to start easily.

The first issue Mind Flayer ran into with prep was an ESC fire. The Repeat Robotics 2-in-1 Dual ESC worked at home on the bench, but unfortunately cooked itself while testing at the Hive. I’m assuming something in the wiring shorted since protective measures like current limiting were at play but the result is the same: it was dead. To fix this, I swapped in new Sequre 70A AM32 ESCs. Though I lose the compactness of the 2-in-1 the ability to change one component individually and the greater amperage rating allows it to be current limited well within the controller’s function ensuring they never get toasty.

After I learned that Mind Flayer drew Maximizer as its first fight I was thinking of ways to ensure I could handle the power of the horizontal. Thanks to using some connections, I was able to source 1/2″ Tegris, a woven material like Carbon Fiber but with polyurethane replacing carbon strands. This made for an incredibly light (and incredibly stiff) wheel option. I machined them out on the home router then attached them to NylonX pulleys.

To go along with these wheels was a slightly smaller blade with a new pulley hub. The weapon system is essentially the same as Demogorgon so it has all the same costs and benefits which were acceptable for a first version.

Since there wasn’t too much to change about the robot (it has only fought twice to this point) the machine is largely unchanged from how it was at Motorama despite the aforementioned changes. Because of that, I utilized the 3D printer to make a name and graphic for the machine. All in all, I’m quite pleased with how it turned out!

After final assembly the bot was weighed and readied for competition! I really like the look of the woven patterns of the Tegris and Carbon Fiber, dark colors of the blade, chassis, and tail all contrasted with the bright colors of the name and graphic. Now off to the event then to fight Maximizer!

Maximizer

The first match of the day didn’t go too great for Mind Flayer as the stiffer Tegris did very little to absorb the energy of Maximizer’s weapon aside from the layer delamination. This transferred the shock to the drive pulley which cracked thereby losing tension on the drive belt and killing drive on one side. Ultimately a battery wire got nicked on the inside, killing the bot and causing a knockout. Though it lost, there wasn’t something obviously wrong so the robot was fixed up and ready for combat. As for the damaged Tegris wheel, it was given as a spoil of war. Now onto its 2nd fight against Blue Cheese!

Blue Cheese

Though Mind Flayer functions very differently from Demogorgon, its weapon system is essentially the same and Blue Cheese did an excellent job retiring the last Demogorgon. As a result, Blue Cheese’s incredible weapon managed to spin down and yank the blade off its mount. The hub is primarily constrained by two flanged ball bearings where the flange is keeping the weapon in place (as illustrated by the remaining flanged bearing on the far side of the weapon shaft). Therefore, when Cheese pulled the blade out, away from the body it put all the stress on this very small part thereby ripping the weapon off. In Demogorgon this shouldn’t be an issue as it was an undercutter so any force upward should push it into the rest of the robot which could absorb the load but the strange orientation on Mind Flayer changed this dynamic. Though the ball bearing was destroyed, the weapon and its hub are still in good shape so they could be used on something or perhaps cleared out for something else, only time will tell.

Post-Event Thoughts

It was a bit annoying that Mind Flayer couldn’t do more in combat, but enough was learned that can justify a proper version 2. This version was a shot in the dark, a concept that could only be properly understood in testing and could not stay in theory alone. The weaknesses of Demogorgon reemerged against Blue Cheese which was a bit annoying as it resulted in the robot dying rather quickly but nothing else was damaged to severely as to keep from being used in a new version; all the expensive parts seemed undamaged. With that in mind, Mind Flayer will go back to the drawing board and hopefully return and really shake up the game.