Making the top 16 a BattleBots is a big deal. It's huge. It's gargantuan. It's massive. It's... ok I'll stop, but we were very excited to make the top 16 - after all you can't win the nut without making the Top 16.
This is a matchup I'm pretty sure we all knew was coming as soon as we saw the brackets, right? After weeks of waiting, it's here. Well, it's here again as we've actually fought them before at Maker Faire Orlando in 2018. We won in a KO and went on to win that entire competition (and we're actually still the reigning World Heavyweight Sportsman champs). But BattleBots is very different from Orlando - so keep reading to find out if history repeats itself or not! Spoilers ahead!
Mammoth is a weird robot. I don't mean that in a bad way either - that's their whole deal. They are so different from everything in the competition and everything else that's ever existed, that you can't fight them traditionally - at least not easily. The robot is 90% air, with tiny wheel and weapon pods, and a crazy high-torque 'spinner' than can toss robots (or Mammoth itself) across the arena and through the air.
Preparing for this fight we had to make a few decisions. The long arm was the obvious choice, as Mammoth is so huge we wanted as much reach as possible. For the Hammer head, we decided to use Lil' Rusty. Partly this was because Ol' Rusty was damaged in the previous fight - but mostly we didn't want Mammoth to be able to get a grab on the long tail of the Ol' Rusty hammer. Lil'Rusty being smaller - there is less to bite onto.
We decided to keep the ablative armor on the front as it adds a good amount of weight over the front wheels which reduces hammer hop. We removed the forks/prongs however as we didn't need to be low and didn't want to get stuck on the floor - there really isn't much to get under in Mammoth. The weight from the prongs was then repurposed to make large 1" thick UHMW shields for our entire hammer chain system. Mammoth doesn't have a lot of kinetic energy in their 'spinner' but what it can do is tear a chain off pretty easily - and it's one of the few robots that could actually reach our chain. After these changes, the robot looked like so:
At this point we were confident Mammoth wouldn't really be able to do any damage to us, other than scratch the UHMW. But Mammoth doesn't usually win via damage - it wins via control and aggression, or even arena-outs. A good strategy is key, what use is an undamaged bot if you still lose?
Since we have a lot of magnetic downforce, we were also pretty confident that Mammoth's weapon wouldn't be able to lift us on its own - there wouldn't be enough to grab on to to pop the magnets. Effectively, we felt it would just be a pusher-weapon and shove us around. So a big part of our strategy revolved around making sure not to fire the hammer directly into their weapon while it was operational - this would pop our magnets and give them the opportunity to flip us. Then it was just a matter of getting around the side to take out their chain/wheels - or waiting for their chain to pop. Mammoth uses the same exact chain size that we do - but puts much more force through it to generate their high torques. We thought they were pushing it too hard and it may even just break on its own - especially if they used their metal arms which don't absorb shock like the UHMW ones. As far as getting around the side - look how wobbly Mammoth is... we can just slide under their bent UHMW outriggers after a minute or so right?
But the thing about BattleBots is everyone is constantly making adjustments. Before our fight, Mammoth indeed made a few adjustments. They added big UHMW hoods to their wheel pods to absorb our blows, and they actually went and got new material from team Huge and remade their outriggers with a new mystery plastic. This new plastic that was much stiffer. UHMW is a great flexible material - but for the outriggers on Mammoth it was too flexible. The new material promised to keep Mammoth planted to the ground while maintaining UHMW-like durability - would it work? Let's find out!
For this fight, you can feel free to replace the entire audio track with the audio from this video. Anyway, all they can really do is push us like we expected. They were able to pop the magnets on the last toss - but they still couldn't get enough of a grip to get any lift - it's mostly just a big push. We can take this all day - but that won't win us the fight. We need to get some hits in.
We almost got around the side. But Mammoth's front left out rigger got stuck in our front armor and we got stuck. Instead of pivoting around for a perfect wheel hit - we missed. The hammer hop then allowed them to get under our corner and flip us - exactly what we didn't want. I will say though, look how smooth that self right is! Now we are in a down position judging wise and we need to start coming back. At this point, the fight got very hectic. Mammoth's maneuverability was much better than we'd ever seen - those new plastic outriggers were working a LOT better than we expected, and they were able to be in the right position all the time thanks to some great driving by Ricky. We took every chance we could to fire the weapon. As long as we weren't directly in front of their spinner, we were firing. There were some misses, and also this nice hit on their left wheel.
This was a great shot - but Mammoth kept on trucking (Mammothing?) and the fight kept going. Eventually, this happened:
What a snipe! The chain goes flying and their weapon is dead. With Mammoth weaponless, we could fire at will, and we did. But as we know from the Malice fight - that doesn't always end well. Firing the weapon gives up control points in the pursuit of damage.
A lot of these sequences looked like Shatter! was trying out for the olympics with us flipping ourselves all over. Unable to get around the side because Mammoth was so wide, we'd come at them head on, pop our magnets, and flip ourselves... this wasn't working out well. We flipped ourselves 4 or 5 times by hitting them because they're just so gosh darn tall.
Eventually Mammoth got us up on the screws - or rather, the screw housing. This was actually very nerve wracking - I thought we were going to get KOd! In reality this was only a couple seconds, arena-side it felt like an hour. The back of the hammer head actually got stuck behind the screw housing, so we couldn't retract it. Luckily Paul was able to work out a swing that got us off the screw housing by firing the hammer hard enough to launch us forward. But wow that was stressful. The hop also set us up perfectly for this hit:
We were stuck on their outrigger though, and couldn't move to realign for any further hits. But basically, a nice bullseye on the wheel pod. We thought maybe this had killed them, as it seemed even they couldn't move, but eventually they started up again. Maybe a shock reset on the controllers?
But, tragedy strikes, and eventually our hammer dies as well! We tried resetting the controller a bunch of times - but nothing. So much for Mammoth not being able to do any damage to us! Without the hammer, it turned into a pushing match, which prompted a fun quote from Ricky, captain and driver of Mammoth:
I'll need to save that screenshot for all the people who say Mecanum Wheels can't push. It's hard to tell sometimes what's happening when I'm driving Shatter!, many times it may look like we're being pushed when actually I'm just trying to drive sideways away from a push (turns out Mammoth is faster forward than Shatter! is sideways). I need to work on the optics of it for sure. But when we actually try to push (and we aren't firing the hammer and popping our magnets), then this happens:
That move was very satisfying. Check out that left wheel straining under the torque, it's totally stalled. Pretty wild. Those new outriggers though - still pretty darn solid! That new material really helped out their drive system and overall control. After a little more shoving, and a few kill saw sparks, the fight ends... but wait, what's this?!
I sure do wish that had happened 20 seconds earlier. And is that wheel dented? Turns out that's not the wheel pod we punctured, but it is the wheel we'd hit directly earlier in the fight. Direct hammer hits usually aren't good for overhung wheels, but I guess this one needed a bit of stalled out pushing to work it's way off.
A fun thing about the broadcasts on TV is we get to see the slow mo, and if you watch the slow mo slowly enough, it turns out Mammoth's chain actually came off before we hit it:
But wait, there's more! They also showed our very first hit of the fight in slow mo...
We can't tell exactly what we're hitting here - but it's something up in that sprocket/chain area. As we mentioned before Mammoth is pushing their chain very hard. Even a small hit on the chain/sprocket could cause enough of a stress riser for it to break itself later. Maybe we actually did hit something on that first swing after all!
I'm glad I wasn't a judge for this one trying to piece out what damage was 'deliberate' or not.
At the end of the fight I was sure we lost - and I talked to Ricky later and he also thought he lost. Truly an even fight when both teams thought they lost!
After the judges decision (during which they paused for about 45 seconds to make us wait for what the 3rd judge decided) we were ecstatic. We were still in the tournament and moving on to face End Game. What a wild ride of emotions that fight was.
Thanks to Ricky and the Mammoth team for putting on one hell of a fight for the ages. No one expected either of us to make the top 16 coming into the season, and I was happy both our teams were able to show that you don't need a high KE vert to be competitive. It's too bad we couldn't both make the top 8, and I can't wait to see how Mammoth evolves their totally outside-the-box design and keeps us all guessing again next year.
After the fight, Mammoth signed the broken axle shaft from their wheel and gave it to us. It now sits proudly on our trophy shelf.
On to the damage report!
I say this a lot, but BattleBots is a game of inches - millimeters sometimes (certainly, it's a game of mixing units). Check out the hole we left in their wheel cover. And the dent on the motor underneath! If we'd been a little more centered we may have been able to really dent the motor instead of sliding off. And look at that Whyachi switch! An inch the other way and we'd have taken that out. An inch either way would have likely been an immediate KO. Crazy how close things are sometimes. Other than that there's of course the broken shaft. broken chain, and some bent bits and bobs all around.
On our end, the majority of the visible damage was scratches to the UHMW and missing aesthetic triangles. We also noted a bolt sheared in our protective UHMW cover - probably from being tossed and landing on it.
But what stopped the hammer? When turning off the robot in the arena the power was already off on the weapon (there were no beeps or lights). We thought maybe the power switch had busted, but it was fine. So then we thought maybe it was a thermal cutoff on the ESCs - but that wasn't it either. After digging around in the wiring we found this:
A wire had melted out of a Castle connector and the system lost power. I haven't used Castle connectors since 2016... which means this is a very old component of the wiring harness which was probably made for the original Mega Melvin back for Orlando Maker Faire 2016. Apparently, all the climbing we were doing on Mammoth, and all the self righting, was using a LOT of current. This wire didn't like it and melted out. We removed the connector and replaced it with a continuous length of wire - this connector wasn't even needed, and now we have one less failure point moving forward.
It's always nice to find these failures in a win, rather than lose because of something like this. We're lucky this didn't happen when we were upside down!
After looking at the damage after this fight, it feels even closer than it did in the arena, with each of us super close to knocking the other out. Their wheel held on just long enough, we missed their switch by just enough, and we melted our wire out while right side up instead of upside down. Nail biter for sure!
With that, we head to the top 8 and End Game. We've fought them before (featherweights at Motorama in 2019) where we won via KO. Can we do it again with heavyweights? Tune in Thursday to Discovery Channel (or Discovery+ ) to find out!
Don't forget to check out more pre-fight, post-fight, and pit content on our new youtube channel:
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1/17/2022 07:15:17 am
Looks like one of the gifs in this article got replaced by a gif of Shatter v Subzero 2022
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