Bone Dead Robotics

This is it, the grand finals. All the year-long strategy comes down to this event with all of the highest stakes. The prize pool is certainly one high stake as NHRL’s finals boast the largest prize pool of any event with a whopping $15,000 for the 30lb champion with $6,000 for the runner-up. That money would certainly be nice for all the robot related and non-robot related activities but for this team the greatest goal of the event is to defeat the best.

For years, the best in the weight class has been Emulsifier closely followed by MegatRon. Phenomenon has a long history of fighting MegatRon dating all the way back to its first year and Vorion has begun a running record against Emulsifier but both machines have yet to capture a victory against their rivals. This is the heart and soul of the competition: to defeat either or both of these machines. Few things are so enthralling as an unproven concept and both of these machines have yet to defeat their greatest challenges once so this event has a laser-focus on doing that exact thing.

This is by no-means a disrespect of the other competitors; the hardest fight you have is always the next fight. When you look at the bracket (as shown above with Phenomenon in purple and Vorion in orange) you can see how so many fights are championship-level for most other events. Phenomenon draws close friend and Team Mammoth-teammate Moccasin in the first round whose reach alone makes it nearly impossible for a dense vertical spinner to damage without extreme driving precision. Though Vorion has a bye, it would fight either Mirage (who fought Phenomenon twice in June) or Pegasus from Equipe Troia of Brazil, a very solid competitor in its own right. Vorion has had trouble with similar drum Yahoo in the past so it still poses a significant risk. In reality, the goal of “defeat the best” includes everyone here so even a single one at the competition is one to be proud of.

Preparation

Vorion

The last time we saw Vorion on this blog was the June TEAMS event at NHRL where it got destroyed by Pepe Silvia and crippled by CRACK? The details of the event were explored in its post, but the summary is that Vorion had a very rough time leading to the retirement of the original chassis that won the team’s first golden dumpster back in August of 2023. This meant that now there was only one Vorion around and that simply couldn’t stand so it was time to make a new one.

The assembly of another Vorion went along very smoothly. Unlike the original that was machined on my own CNC router it was outsourced so when the components arrived it was fairly straightforward mechanical assembly. The electricals are slightly different from the other machines as it utilizes the Flycolor 120A that I re-flashed to AM32 after pulling them from Fracas but is otherwise the same.

Phenomenon

Phenomenon was in a strange situation after winning the June event. As referenced in other blog posts, since the machine was able to flow through the June event without heavy damage. Losses are more instructive than wins so without having losses there was nothing large to learn. Even so, it was important to analyze the machine and capture any damage.

The hidden damage from the event was the magnet ring. The core of the hubmotors were pulled from the stock 4520 470kv motor which was not designed for the abuse we’re putting it through. While it was functional in testing and wasn’t readily apparent, getting a look at it anyway revealed something that easily could have been an issue if it ran again.

Mental Game

The really interesting part about combat robotics that I’ve been thinking about for years is how if it’s a sport but a tech-sport then it has to be very similar to traditional athletics but slightly different in others. It is similar to basketball, football (American and otherwise), baseball, hockey, tennis, and more in that it requires an incredible amount of preparation in so many aspects of life prior to competing with similar emotional highs and lows. It is more similar to F1 in that it is more about a person working with a machine to accomplish a goal but different in that the engineering and athletics are frequently one in the same person(s). This inherent connection creates an interesting interplay; you don’t have to exert yourself physically before the competition to ensure bodily prep but you also can’t avoid the natural intensity of an athlete to study film of the opponent, have a pump-up playlist, or some other pre-game preparation that an Olympian down to a little league player all can experience. Yet you are also an engineer so you will inevitably pour over your machine looking for every last detail or think of possible modifications to get that last extra percent over your opponent (something which almost always happens as you are watching video of your opponent). Combat Robotics is all these things in one and I’m sure one day I’ll dive into these in greater detail but for now, back to the prep for this event.

Since robots were largely good, it was time to think about the last variable of the equation: myself. I like to describe my robots not as children or pets but like an arm or a leg; an extension of my will that I closely control. If Vorion and Phenomenon were to serve as my metaphorical right and left arms then I must use them well. One part of this has been going down to the Hive and running many tests on the machines that will be detailed in the 2024 breakdowns for each machine. The ability to practice is invaluable and my relatively close proximity to and generosity of Team Honey Cracked has been the greatest asset in finding every little issue and rooting it out. This is very much the same as any athlete performing warmups. An even larger part is making sure your head is in the right space. The worst feeling a competitor can have is to get into their own head on things so a healthy dose of perspective stands out as essential. You have to remember:

1. It’s the Finals so everyone is good. There is no “expecting more” when the only guarantee given is 2 group fights where you could lose both. The next fight is always the most dangerous.
2. Arriving at the Finals is an honor in itself. No matter the outcome, people all throughout the year would desperately want to switch places with you so you’ve already proven your efforts.
3. Set reasonable goals that don’t depend on your opponent. While I would love to get a rematch against Emulsifier and MegatRon for earlier defeats, a lot of variables have to go my way to allow for a rematch. With that in mind, its better to focus on the bot’s own progression and your own responses to situations since those are things you can directly affect. This won’t be the last robot fights of all time so it’s good to have eyes toward the future.

Competition

Friday

The competition started like any other with arriving at NHRL the Friday before competition and setting up the machines. We joined our friends at the Sleepy Anime Girl Club with Chainsaw Kitty and began to spread out. We were in a dark area of the pit areas so Jimmy at NHRL provided some pit lights (thanks Jimmy!) while we prepared for safety. Phenomenon got through safety very easily with Vorion requiring some more testing to double check radio issues (this was a foreshadowing). Our friends at Team Honey Cracked also provided a minibot base to work alongside Vorion since it ran one earlier in the year (thanks for the help!) and was to serve as support in fights against other minibot teams. Vorion ultimately safetied Saturday morning as the minibot assembly was finished and Vorion was comfortably functional.

One thing that really stood out in safety was Phenomenon’s lightness versus Vorion. By the NHRL scales, it was almost 2.5lbs lighter than Vorion in each configuration. This was known somewhat at home, from preliminary checks but this really came to bear when I had to take off components from Vorion for the first time to make weight. This will be a thought lingering in my head for future changes in 2025.

Saturday

Now its fighting day! Vorion being 3 seed had a bye for the first round but would fight the winner of Mirage vs Pegasus. Phenomenon then prepared for the event opening fight against Moccasin.

Round 1- Phenomenon vs Moccasin

This fight was an excellent back and forth and one of adaption as well. Moccasin’s greater size did an excellent job funneling Phenomenon’s size and controlling it most of the fight but gradually I was able to get a rhythm and maneuver enough to catch the front attachments. There were moments where Phenomenon was able to position itself and get big hits on Moccasin’s chassis but once the cam lifting arms were removed there were far more moments to attack.

Unfortunately, this fight also revealed a key weakness of the hubmotor: stalling. Though the larger 4520 motor and aluminum body of the hub was good at keeping heat away from the windings, the Rhino ESC got extremely hot as everytime Moccasin sucked in the blade and caused it to stop and stall until I had to manually turn off the weapon. In the last 20 seconds went down and I think this was a direct result of that stalling. By the end of the fight I read >150F on the ESC and ~90F on the weapon (which is nominal for use). I theorize that by the end the ESC was hot and one of the impacts knocked off the already weakened solder leads and ultimately shut off the machine. Phenomenon lost on a 8-9 decision for Moccasin but it was a good time for all with minimal repairs so it was time to prepare for Round 2 against Mr. Roper. 0-1, Judges’ Decision.

Round 2- Phenomenon vs Mr. Roper

This fight was deceptively difficult. To begin, while the hubmotor controller was switched out to a Sequre 120A ESC and tested well, something seemed to go wrong with the machine while in the box so the weapon was only idling most of the fight never at full rev. As for Mr. Roper, it had a very solid minibot in the form of Night Crawler which could certainly do some damage in the right spots.

The fight itself was madness (as usual for a fight with Mr. Roper). Since the spinner had its issues, this was a fight that would heavily rely on the lifting arm. This was the core idea behind the lifting arm: it was a critical backup system in case of the main weapon going down. If this were a normal vertical spinner, the fight would have turned into a much more boring time and Phenomenon would be very likely to lose since the dead weapon would count as damage. Though Night Crawler was able to bend the forks (which were already fatigued from the fights in June), the lifting arm kept doing its thing throughout the fight. Fortunately for me, Roper had a mystery fire and repeated rams of Night Crawler killed its weapon. Night Crawler was able chew up lots of parts on the top machine including just missing the lifting motor. Once again, a great reason to bring that subsystem inside the machine. Ultimately Phenomenon won and was set to fight WarHard XXL. 1-1 Judges’ Decision

Round 2- Vorion vs Pegasus

Vorion’s fight against Pegasus was one that I was mentally ready for, but disappointed by the bot’s response to it. Though everything was looking good upstairs with a clean test in the test boxes, both Vorion and the minibot immediately had issues. As we were powering on, the machine did not respond to radio signals and began going crazy. Fortunately the weapon did not start up and it was no more an issue than pinning the bot down while I power cycled it, but it was a very ominous start to the fight. After the machines were cycled and seemed to gain control, they drove to the circle and began the match. Pegasus was able to get a quick shot on the machine and bend up the main fork which was annoying but still within my ability to operate around. However after that, Vorion stopped moving and let out a quick flash followed by fire. After a seemingly tiny hit the machine had just blown up. Though Phenomenon had not won against Moccasin I was still satisfied with it as the bot performed to its upmost and the loss revealed new limits I had not previously considered. This, however, greatly annoyed me as the robot clearly gave up electrically long before it should have mechanically. Once again an example of tiny details that can’t be proven in testing but always find their way out in combat. 0-1, Knockout.

Round 3- Phenomenon vs WarHard XXL

This was going to be the most brutal fight of the day by a longshot. WarHard XXL was actually at the June event that Phenomenon won but due to electrical issues was unable to get into the tournament and didn’t stop Phenomenon’s run to victory. That being said, I knew that WarHard’s weapon would be an incredible test for the hubmotor. In short, if that hubmotor and its bearings could take nose-to-nose shots against this beast then it really was going to last.

Since Phenomenon did not have a mini due to not running one earlier in the year, I knew it was going to be a struggle with the minibot as it tees it up for shots. Even so, I knew ultimately the question was simple: “can I take a hit?” The first few exchanges left it with a resounding “sort of” as the machine was still together but clearly rattled after WarHard tore off the fork and set it flying end-over-end and open to more shots. After the initial onslaught, Phenomenon was able to get going and was miraculously still spinning so it fired up and deliver a firm shot to WarHard. It was twisted and limping, but it wasn’t dead.

Sadly, the twisted chassis made maneuvering hard so the great sin of letting an opponent get a free shot was committed. The TPU guards kept WarHard from directly delivering power to the machine, but the bounce and gyroscopic forces ended up rotating Phenomenon in the air, allowing the weapon to land askew of WarHard’s weapon and allow all the energy to pry the system apart. Despite the horror, Phenomenon’s weapon was actually fine. Because the hubmotor was a self-contained item with only the 10-32 endtapped screws holding it in the frame rails, it actually left the chassis as one solid mass with only minimal damage to the endcaps and no damage to the motor or bearings. After the fight it was still able to rotate freely and could likely can be reused if further analysis revealed no other issues.

This shot however did reveal the exact same failure mode as Vorion had against Pepe Silvia at the June Teams event. This was a foreseen weakness in the switch in the new platform (as discussed in Vorion’s 2023 review) but I am surprised it happened to both machines. While it’s not a common occurrence, it is a failure mode will certainly be addressed in future updates. 1-2, Knockout. Out of the Tournament.

Round 3- Vorion vs Synthesis 30

Due to the nature of my machines, they essentially ran back-to-back. Due to extra time taken to dissect Phenomenon after the fight to ensure it didn’t catch fire, it was right as I returned upstairs that I heard the call for Vorion. Fortunately I did prepare the machine most of the way, certainly enough to fight if it had to, but it had two key issues that both showed up in the box: unground fork tips and radio craziness. The unground fork tips are pretty self-explanatory; to ensure the forks don’t get stuck on every crack in the floor I bevel the tips some so they glide over. It risks losing the ground game to other wedges but it gains maneuverability which is far more important especially since the forks are so narrow by comparison. This meant that during the fight Vorion got stuck often and allowed Synthesis and its mini bots plenty of opportunities to corral it.

The biggest issue was the radio. Though this was the second Vorion so it was basically unused, the R84 receiver once again had response issues even in the test box upstairs with one of those issues being the lifting arm being twitchy and unresponsive. As I was being called down, I had to swap in a new R86 receiver and program it to failsafe correctly. Fortunately it did failsafe but the arm was still unresponsive. This came back as Vorion once again lost due to the lifting arm being stuck and unable to self-right. Though Vorion did receive solid damage from Synthesis, drive and main weapon were still fully functional though none of that mattered once the lifter had died. It was another frustrating electronics issue that kept the mechanical ideas from seeing their full. There was the comfort in seeing Synthesis go on to defeat Emulsifier, but that also meant I wasn’t able to test my own ideas. Another thing to look forward to in the new year! 0-2, Knockout. Out of Tournament.

Sparky Award!

Even though the robots didn’t win, I was able to! I was given the ‘Most Valuable Builder’ award which represents being a good builder and member of the community. It was an honor to be recognized both by NHRL and my fellow competitors and I hope things like this blog are helpful tools for people to not only understand this wonderful sport and all of the complex engineering teaching it provides but also as references for new builders who may be able to use these learnings to build machines of their own and grow into even greater builders in the future.

Post-Mortem

After the event, all machines were put onto the hand truck and carried out. From right-top to bottom-left here are the status of each machine:

1. Mostly functional, need to verify the lifter controller for functionality but very likely could fight again as-is.
2. Need to replace drive ESC and confirm drive motor functionality but should work. Need to confirm receiver functionality. Need to replace damaged wheelguards
3. Replace damaged frame rail and bracer. Replace lifting arm controller and motor. Replace destroyed wheelguards and check wheels.
4. Salvage what can be removed, prepare the rest for burial.
   

A disappointing end for the machines in 2024, but now on to 2025!

Check out each of the robot pages as they will go even further in-depth on each machine’s development throughout the years!