LA Maker Faire Bash 2019 Event Report
After a pretty quick turnaround from Vegas, I hammered out the new versions of Sandstorm and Faultline in time for LA Maker Faire Bash this past weekend. I’d say they performed pretty well for new bots. Far better than their predecessors.
Sandstorm
I’d consider Sandstorm to be my flagship bot. Every iteration has forced me to try something new with combat robots and this version is no different. Here are a couple of changes between V3 and V2:
- UHMW plate based frame, upgraded from an expensive 5-op billet aluminum monstrosity. Estimated $40 in material cost per frame vs $120+.
- Same brushless powertrain setup — SK2118 3100KV motors into 19:1 22mm servocity gearboxes. This time, rather than direct drive one of the wheels, both wheels are indirectly driven with a 2.6:1 GT2 belt reduction to help offload cantilever and shock loading from the gearbox output shaft.
- 1.5" custom TPU wheels which performed better than I expected when combined with magnets.
- Upgraded weapon power from an 800KV motor through a round belt reduction to a 2700KV motor through a GT2–3mm timing belt reduction.
- Same 4.7" diameter weapon disks from Sandstorm V1 and V2.3
Fight 1 — Vs Under the Bed
One thing that stood out to me throughout the entire event was the sheer number of horizontal spinners registered. At recent socal events, there have been one, maybe two horizontal spinners per event, but at Maker Faire, 7 out of the 10 robots in the 3lb class were horizontals. Prior to the event, I expected the usual distribution of robot types so I prioritized printing extra wedgelets over printing a mount for my titanium wedge configuration. Big mistake.
Under the Bed is Kenny Hu’s new undercutter bot. The COTS edger blade was sharp enough to do some major damage to UHMW frames. Luckily, I was able to rush him fast enough to clip one of his wheels in the opening move and knock him around a couple of times throughout the match. In what would be a common theme throughout my fights, I was having some weird binding issues with the left side of my drivetrain which hurt my mobility at some points in the match. Luckily I was able to clip his weapon bar in just the right way to knock him out of the arena and win the match.
Result: Win via Ring Out
Fight 2 — Vs Explosion
Explosion was the next horizontal spinner I faced. Tommy Wong built one of the toughest and most destructive beetleweights on the west coast in Explosion. Featuring an all TPU frame and a Silent Spring-esque design, it’s been making its rounds as one of the most dominant robots in 2019.
In the opening move, I was hoping to rush him to hopefully dissipate some energy from his spinner before it could get up to speed. I was stopped by a new drivetrain issue — the latex coating on my replacement wheels delaminated and jammed itself in the drivetrain. I spent the entire fight crab walking which gave Explosion enough time to circle around me and cause some damage to my frame. Luckily my frame geometry prevented any significant damage, but eventually both sides of my drivetrain jammed up due to latex tread delamination and I was forced to tap out and fall into the loser’s bracket.
Result: Loss via Tap Out
Fight 3 — Vs Spinnie the Pooh
My third horizontal spinner opponent was Spinnie the Pooh. It was an interesting carbon fiber 3D printed frame with an undercutter blade. In the opening hit, I was able to disable his weapon and start controlling the fight.
This fight was going incredibly well for me since I started chipping away at his structures. I was sure that even if it went to judge’s decision, I could take the W on damage and control. That all ended when my weapon began to spin down and I heard my robot reboot. My transmitter was unable to regain connection and I was counted out for a Loss.
I later determined the issue to be related to the BEC that powered my receiver. It did not regain power as expected and I couldn’t continue the match.
Result: Loss via KO.
Bonus Fight — Beetleweight Rumble
In the rumble, I was the only vertical spinner in the box. I lost my weapon belt early on due to an impact by one of the other robots, but the drivetrain started performing better than it ever has and I felt like I was controlling the pace of most of the rumble. In the end, something in the left side of my drive started to bind again and smoke started pouring out of the vents on Sandstorm. I’m still not entirely sure what caused the initial issue, but with all of the heat generated in the smoke-out, the 3D printed motor mounts began to melt and that sealed the deal.
Result: Loss via KO.
Event Result: 7th place, eliminated in loser’s bracket round 2.
Final thoughts on Sandstorm: I was very happy with how it performed when at full throttle and was pleasantly surprised at how well it performed with issues. At this point, I just need to hammer out some reliability issues and come ready for horizontal spinners at the next event.
Sandstorm will fight again at Sparklecon Smash in January.
Faultline
I’m really happy with how the new Faultline came out conceptually. It addressed one of the biggest issues with the old version where iterating on and upgrading components was difficult. In this new version, the left and right sides of the drivetrain as well as the weapon were all replaceable modules that slotted together very quickly.
The new larger vertical spinner was made out of solid PLA vs ABS of various infills which meant that it was far tougher and harder than before.
The wedge configuration was an incredibly beefy 1/4" thick solid PLA so it was equally robust.
The biggest issue with faultline was my drive motor selection. I had chosen a particularly slow N20 gearmotor with the faster ones I had on order being stuck in the Black Friday/Cyber Monday mail hellhole, to be delivered after the event. The installed motors were far too slow for the robot and I wasn’t able to move around as quickly as I’m used to.
Fight 1 — Vs Free Hugs
Free Hugs was a fun robot to fight. I brought my spinner configuration since I knew it could do some decent damage to its ABS frame with it.
At October Obliteration, I was able to clip off Free Hugs’ left wheel guard with Fautline V1. In this fight, I completed my collection by clipping off the right side wheel guard in the same fashion.
After that, Free Hugs spent the rest of the fight hugging me into submission. I was able to chunk out parts of the frame, but nothing significant enough to win the match.
Result: Loss via Judge Decision.
Fight 2 — Vs Slicer
Slicer is the twin of the robot that I lost to in October, Dicer. Slicer is driven by Andy Hedge’s son Logan. Both robots have destructive horizontal spinners, so this time I fielded the wedge configuration. I was pleasantly surprised to see the wedge hold up to the spinner, coming away with only an orange scratch across the face.
Eventually, Slicer hit the biggest weak point of my robot, the wheels and treads. a quick hit cut the O-Ring treads I was using and I was left without traction and mobility until I was counted out.
Result: Loss via KO.
Bonus Fight — Plastic Antweight rumble
In this 3-way rumble, I fought both Free Hugs and Slicer. I was having the usual mobility issues, but I was able to outlast both robots to win the rumble through careful positioning. I wish I could say more about this rumble, but Faultline honestly didn’t do much other than survive.
Result: Win
Event Result: 7th Place, eliminated in loser’s bracket round 1, winner of the rumble.
Final thoughts on Faultline: the new design was as robust as I’d hoped and I think I’ve set myself up to better iterate better on the weak points of the design. I expect to have a better performing drivetrain and another weapon configuration option for the next one.
Faultline will return at Sparklecon Smash in January.
Enjoy this highlight reel of both robots this weekend: