I was at Denver Maker Faire for about 30 seconds before I started planning the bot I would bring next year. Cpt. Hook's design was proved to be solid structurally, but fundamentally ill suited to the competition. At Denver Makerfaire I networked with several other CO bot builders, and we are going to attempt to collaborate on a modular combat robot platform. The platform will feature a common drive base and a standard mounting arrangement for attaching weapons.We're planning a roughly 50-50 split of drive train to weapon mass. The initial designs are starting to look good:
I am still really excited by the idea of a crushing robot in the 3lb weight class. However, I'm a little burned by Cpt. Hook's performance so for at least my next bot I'm going for something a little more dangerous:
My collaborators have some other interesting ideas that they are working on too. I'm hoping we'll be able to field roughly 4-5 bots by next maker faire, and that we'll have a prototype ready for Rocky Mountain STEAM Fest in April.
Cpt. Hook was a good first attempt at a combat bot. I'm satisfied with how he turned out, but I now want to change 100% of the things I did on him. On Sunday at AVC I entered him into a few rumbles against some beetle weights and his armor held up really well. At the end of the day I had the chance to see him off in splendor, so this is how Cpt. Hook died:
In the end, his mono-body armor was remarkable strong. The aluminum armor wasn't ideal, but the method of construction proved itself. After 3 hits from poison arrow I was able to reconnect the battery, attached a fresh wheel and drive. Overall, I call him a success and next year's bot is already in the works.
Cpt. Hook Doesn't Do Very Well
Okay, so Saturday was the initial rounds of the main tournament. You can view the tournament bracket here. Captain Hook ended up going 1-2 in the tournament, fighting 3 robots without active weapons. I can't complain too much as Cpt Hook's weapon wasn't exactly "effective." The end result was 3 matches without even scratching the paint, and I was out of the tournament. It was a pretty disappointing result, and I'm definitely going to make sure I have a bit more of an active weapon next year. You can see the fights from Saturday here.
The judging process used is a 3 point system, one point each for Aggression, Control, and Damage. Of the fights I watched, I would say only matches in the first 3 rounds of the tournament regularly ended in knock-out. After the first time builders had their bot's dismantled, the competitive bots just didn't die inside the matches. If you want to make it near the end of the competition you need to play the scoring system and win over the judges. Judging seems highly biased towards mobility and driver skill, good wedge robots are able to win on judges decision by just driving around their opponents. I've already talked about how Cpt. Hook was too high-speed and low-torque to be effective, but this was even more true than I expected at the competition. He was also too responsive on turning, and not controllable enough in straight line. I could/should have resolved this by simply moving the wheels further out from the center of the robot.
Armor vs. Structure is a big deal for most robots. Cpt. Hook was the only "mono-body" robot I saw at the event. By mono-body I mean that the armor and the structure of the robot were the same component. Instead almost all bots featured a core chassis with attached armor panels. Chassis were often plastic at the beetle weight, and armor was typically titanium. UHMW (ultra high molecular weight polyethylene) was featured on a huge number of robots, and seems the plastic of choice. I would have expected to see more Delrin or Poly-carbonate, but UHMW was everywhere. I still haven't come to a strong conclusion about which design is fundamentally better; I suspect that the mono-body tends to fail catastrophically whereas conventional designs tend to be salvageable after damage. Certainly Cpt. Hook's aluminum armor appears to be too soft, and that spinning weapons will be able to bite deeply into it. Titanium and hardened steel armor appears to be able to repulse the S7 Tool steel teeth that most robot use on their weapons.
I've been very busy since the start of September trying to juggle finishing Cpt. Hook while mentoring the local FRC team, so I haven't had time to make updates on the project. However, you can now enjoy seeing the finished product. I made a couple of quick youtube videos which can walk you through the final bot.
This first one is a simple demonstration of it driving and moving the weapon:
In this second video I open up the bot and walk through the internals: