Category: Events

Event reports

Sadbot and Overhaul Go To Comicpalooza: Scale Model Testing Your BattleBots At Full Scale

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Just because all this van stuff was going on doesn’t mean I put down the robots last year. Never a dull moment around these parts! Interspersed between the Operation IDIocracy work over the summer and the Econocrane Saga was a heavyweight sportsman-style event held at the Comicpalooza event in Houston, Texas, by the local organization Houston Area Combat Robotics.

Robots in mid-July in Houston sounds like a great way to get heat stroke, but it was a chance to do some shakedowns and validation on Overhaul that we didn’t really get to do at the 2021 BattleBots season. When you’re at the event itself, you’re really just in survival mode; whatever works works, don’t question it. Getting to run the bot at a low-stress show-off event means I can kinda retrace my steps and figure out exactly what was going on.

Anybody who watched the 2021 season probably saw that Overhaul had some… fire issues. I joked it was probably the 2nd most reliable flamethrower at the competition: It would always catch on fire somewhere around 2:15 to 2:30, plus or minus. Midway through the qualifying fights, I threw in the towel and switched the drive controllers from my 12-FET Brushless Rages to …

vesc

Disgraceful. Why not just go stick my head in the jaws and hit the go-stick at this rate?

The controller I’d worked for not too long and not very hard on… was just not capable of sustaining heavyweight-tier power reliably. The reasons were many, but centered around the fact that the old SimonK firmware, while dumb-of-ass enough to whip start any motor you want it to, was consequently also dumb enough that it never had any facilities for current control or limiting built in. So while they could overpower smaller motors, using them on anything bigger than, say, a 60mm series outrunner was asking for trouble if the motor stalled or there was a lot of reversing. A current-generation VESC frontend would easily handle the 12 FETs properly and cap the motor at whatever current you set it to.

I dish on VESC a lot for being another wayward open-source project turned product that requires a worldwide community of people shotgunning into the dark to support, much like 3D printers were last decade. But the truth is I basically watched the VESC project grow up and its proprietor Benjamin Vedder become a self-taught motor control engineer. He worked a lot with my buddy Shane who featured abundantly on this very site in yesteryears. I have only the highest respect for his work in development of the VESC bloodline, which started as a personal hobby project much like I never meant to sell Ragebridges.

Exclusive, never-publicly-shown photo of the Even Bigger Brushless Rage I made for Overhaul in 2021. These boards never made it off the bench because I lost motivation.

The thing that always bugged me, though, is the productizing of the hobby and community. A firmware version change might introduce new features but create new bugs and break old features. Dozens of different manufacturers stray from the project definition and controlled documents to implement their own features, some of which make it back upstream into one of said firmware updates but leave others in the lurch. Software UIs which change with every other version, and so on.

And there is, of course, no fixed documentation because it’s always out of date; the best way to get help is simply to wade through dozens or hundreds of forum posts and social media threads (just try setting up a new VESC using a Youtube video from 2017!). Because I always had my somewhat working controllers, I simply never looked in the VESC direction, and only observed the hand wringing coming from others in the community trying to blaze these new trails in the world of robot fighting.

But whatever the case, it was time to acknowledge that the combined autism of dozens of Europeans and hundreds of Chinese people was far more a force for progress than I could ever be alone. Just like how I’ll probably never build another custom hub motor unless it was purely for, uhh, self-enjoyment.

I did pick up two VESC 6 architecture based Trampa ESCs, confusingly called the “VESC 6 MK V”, right before the 2021 season because I had a SNEAKING FEELING they would be needed. And those were the ESCs which got stuffed into Overhaul. Because the C80/100 motors in Overhaul did not have Hall sensors, I had to fiddle the settings to use sensorless mode.

At the time, the sensorless FOC algorithm was pretty flaky and not great with transient loads,but worked fine for its intended purpose of skateboards, bikes, and hoverboard motor. So, I kept it on sensorless BLDC / block commutation mode, with input shaping like ramp-up times activated and the current control loop gains cranked way too high (a necessity at the time; many of these issues have been resolved in the Present Year)

This made the bot driveable but not superb, and I would have to constantly ‘drive the controller’ so to speak, instead of focusing on the bot itself. If Overhaul looked pretty slippery in the Black Dragon fight and the “Chair Fight” with Big Dill, that was why. I signed up for the event because I figured more stick time is a bare minimum even if I make no other meaningful progress on making the bot drive better.

But there was Sadbot too.

Two heavyweight platforms with allegedly identical powertrains I could use to make delta comparisons, and maybe even fight them against each other! Sadbot was in dire need of a renovation anyways, so I took this as an excuse to organize the piles of stuff that had accumulated on top of it and start appraising what needed a lube n’ tune.

I had bought two VESC 4.12 clones from Hobbyking a while back when I first felt like Brushless Rage needed to be phased out. I supplemented these with a few used units I picked up from someone who was upgrading. These 4.12s are roughly as capable as 6-fet Brushless Rage; they’re going to be underpowered driving a 80mm motor each, but the nice thing is they won’t blow up doing so.

The goal here wasn’t try to run Overhaul on these 4.1x units, but that I didn’t want to spend several hundred dollars on a set of 6.0 based ones for Sadbot yet. If these survive the C80/100 drive motors, so much the better.

Sadbot itself had gathered a whole lot of dust, cobwebs, and metal chips in random spots. Its last action was really Robot Ruckus in 2019, and it’s been pushed around the garage since then. I decided a comprehensive teardown and rebuild of the electrical deck and both Overhaul 1 wheel pods was warranted. So, I just dug in and started ripping everything out…

One increment I wanted to make from Overhaul was using the sensor-integrated C80/100 motors, since much of the development effort seems to have focused on perfecting the Field Oriented Control (FOC) algorithm assuming you have Hall sensors or an encoder.

Fair enough – sensorless starting has a lot more math involved in it, needing bigger and faster microcontrollers, and often requires close-in tuning of inductance, flux linkage, etc. quantities on individual motors. This makes it much harder to get right for a general purpose plug-in controller (In the Present Time, High Frequency Injection [HFI] based pole saliency detection has made its way into VESCs with the latest hardware rev)

The spare motors I picked up for Overhaul before the 2021 season did have Hall sensors, so I went ahead and knocked them apart to switch out the custom-made shafts of the older motors.

The drive pods got cleaned up on all fronts with new chains and lube and new threadlocker in the bolt holes. There were a lot of things which were getting loose and jiggly!

I also took apart the lifter pod to take a look at it all, but it did not need any work. Here’s the reassembled drive pods! They’ll go in last since they’ll make it harder to work on the electrical bay. I’ll finish that first by remaking the wiring to accommodate the VESCs.

Oh yeah! I picked up another Harbor Freight rock chisel thing to make a spare poker. The original Long Pink Member from 2019 was straightened out some, but I figured it wouldn’t live very long if it was bent back and forth more..

Most people using VESCs just throw them in with a bunch of foam wrapped in heat shrink or tape. This approach doesn’t sit right with me (Yes, yes, I know, their robots work and mine doesn’t) and I wanted to try and give them more heat sinking. They’ll be operating close to maximum power handling levels for longer periods of time, driving those C80/100 motors. The obvious problem is that the 4.1x VESCs don’t have a good way to mount to anything because they were kind of designed with being stuffed into a wiring harness in mind.

I came up with a clamping aluminum bar mount that will grab them by the FETussy. The back of the board, with the capacitors, will be secured by a zip tie mount.

The aluminum bar gets bolted into the existing big heat sink plate with a dollop of thermal compound in between.

Here’s how that looks! #4-40 long screws capture the VESCs in between them. The FETs get silicone sheet on the top and bottom for insulation. Heat transfer out of the plastic case on these D2PAK-7 packages isn’t great, which is why Brushless Rage and other controllers have always heat sunk through via-forests in a heavy-copper PCB. But it’s better than nothing.

With the mounting solution validated, I went ahead and worked on the heavy power wiring – extending motor wires, making new battery cables, and so on.

My automotive influence is showing here with all the wire loom. The sensor cables and motor phase leads were run separately to keep the motor current from beating the little Hall sensors …. uhh, senseless.

If needed, I was ready to put them in some conductive loom and ground the ends. Luckily, this turned out not to be needed – just keeping them from running next to each other was enough.

For someone whose entire line of work for over a decade and a half is “technology”, I sure hate technology. Specifically, I’m not personally so much a fan of “just configure it in the app”. Yes, you get much more flexibility and room for features if you have an app. But give me a row of DIP switches, blinkenlichten, and trimmer potentiometers any day.

The cool kids set up their VESCs with their phones because you can get them with Bluetooth now. I, meanwhile, could only find 1 short USB cable to do this with, necessitating this comical and totally safe setup. Sadbot, propped up on one half of a moving dolly, with my computer directly in the line of “Welp it hit the ground and kept going”.

The electrical deck is now all buttoned up with everything operational. The drivetrain controllers are set up in BLDC mode using Hall sensors, but the lifter was kept BLDC sensorless because the 6374 motor running it didn’t have them, and it’s geared down so far it didn’t matter.

I didn’t set the drivetrain controllers up in FOC because for one reason or another, I couldn’t get the FOC auto-detection to take. This may be one of those mismatched firmware, hardware, and software 3-way tangles I alluded to earlier. Dumb ol’ BLDC mode worked flawlessly, however.

Up front, I added something Sadbot has never had up to this point and just got away with: A weapon lock!

Yep, it was finally time. A simple 3/4″ hole drilled in 1/4″ thick steel strips will suffice for putting a bigass square lynch pin through.

Weapon lock all welded up in-place.

While Limewelder was warm, I went ahead and welded the poker solid where the striker interfaces with the tube, just like the old one.

With everything installed and tightened again, Sadbot came in at 220 pounds even! This is the weight of a “classic” heavyweight and what I had in mind when originally designing it in 2015 – the thought was maybe I’d head to Robogames which at the time was still running the 220 pound Heavyweight class. The ample weight allows me a lot of room to mod and add things if I wanted to run at 250 pounds.

Here’s the final hero shot of Sadbot, with weapon lock installed. And a low speed drive video!

I tried to not annihilate everything I owned, but did rip it a little harder in the driveway too. The sensored BLDC setup with the innate current-control loop drove great – I could feel the current limited acceleration, but for the most part it handled predictably. A sharp stop (like running into the curb) could trigger an overcurrent condition which needed me to back off the stick and try again. So I had to be mindful of this, but it only happened periodically. I wrote it off to “50A-ish rated controller trying to wag a motor which could easily drink 200 or more amps”.

The Road to Houston

Houston is about a 12 hour drive from Atlanta; while long, it’s certainly nothing I haven’t done many times before with my Boston to Atlanta (18 hour+) runs. For this trip, I chose the competent van because you should only live one meme at a time. This is also why I have never driven cross-country to BattleBots with a meme van: Don’t put your childhood dreams in series or you’ll cry over their shattered remains on the side of the interstate somewhere in New Texahoma. Live them in parallel with impedance matching.

Loading the robots in turned out to be very easy because I already had my equipment for hoisting heavy things around. Just chain them up and sling them in!

Overhaul was basically pulled out of the crate as-is, where-is, no warranty expressed or implied, no questions asked or answered. To be fair, it did leave the 2021 season ready to run because we were supposed to have another fight.

With all the equipment tossed in after it including handling carts, the Overhaul team tool chest, and spare parts, the reasons why I decided to maximize my automotive Asian Dad Energy for a daily consumable car are abundantly clear.

You can barely do this with a mid-size pickup truck (at least I’d need a bed cap) and the tailgate would be already up to my nostrils. One of my favorite activities is just slinging lumber and 4×8 construction panels into this thing at the Home Depot pro parking shack while dudebros hoist things into the 5’5 beds of their emotional support pickup trucks next to me.

The trip down I-10 was terminally uneventful. By the way, if you’re looking for some lizards, hit these people up! It’s been a very long time since I went to Houston – the last time I recall going was to see family friends when I was a wee caterpillar.

I chose I-10 instead of the more inland I-20 (then cutting south after the Texas border past Shreveport) because E A S Y. I got to see the swampworks of America including the Atchawichyaiwannalaya Basin Bridge among others, and traversing the lights and sights of the Houston energy corridor in southeast Texas was also entertaining.

I left Atlanta around 6AM and cruised into my hotel east of Houston around 10PM, managing to not bomb it the entire way but stop to check out some roadside knick-knack stores.

Next morning at load-in, setting Overhaul and friends up for the visiting crowd! A couple of bots were on display, such as Avalanche from Team Toad behind Overhaul there. It was also competing, so I suppose these were just demo models…

The event being one of only a tiny handful of Heavyweight-scale anything out there meant BattleBots Season 7 prospectives from all over the country also showed up. This is an early prototype version of Horizon, which was being bung together (photo captured mid-swing of the hammer) right up to the safety meeting.

Bunny of Malice set up the merch booth, which we all contributed to in order to satisfy the throngs of onlookers once the con opened.

Besides Overhaul and Sadbot, I also brought a con tchotchke in the form Your Waifu is Trash. This stupid thing has probably seen the most physical miles driven of any actual robot I’ve built, having been to almost every convention I have since 2019. I’ve worn through the brushes on at least one motor and changed wheels because they got too small and worn down from driving on concrete/asphalt.

It’s been a hit everywhere it’s gone, because giving people an avenue to depersonalize their insecurities and self-doubt has never been a flawed business model. I drove YWIT around in between fights, when we took breaks, and when the matches were done for the day.

Pit table shot! I kept Sadbot on the handtruck because it conveniently fit between the drive wheels and allowed access to it in all directions.

One other item I “invested” in before this event was a new charger for Overhaul. I wanted the ability to charge up to 12S lithium in a single bloc, as up to that point, Overhaul’s charger has been a set of 8S-limited Turnigy Reaktors. The battery enclosure had no internal wiring and just ran both battery leads out so I could plug both in. At home or if I didn’t give a shit, I just set my adjustable bench power supply to CC at 15 amps and CV at 49.2 volts (give it a bit of safety margin) and went about my day.

This iCharger X12 came to the rescue! It’s a current-generation charger that takes up to 48V in and can consequently poop up to and over 48 volts, handling over 1000 watts with an ability to regeneratively discharge into a master battery bank. The package is scary small for handling that much power, but I believe in modern semiconductors. In fact, it can overwhelm my puny 24 volt power supply instantaneously, so it’s time to upgrade!

Sadbot had an easy and fun time because of the non-spinner nature of the arena, which effectively dated back to the mid ’00s as one of the original Southeast Combat Robotics (SECR) boxes. One of my fights was with Slammo, who was also here to test out some new architectures and drive setups. This match was fun and tossy until Slammo quit working again, as for some reason it does.

Sadbot also had other fights against some more sumo/sportsman’y heavyweights from locals, and a Mild Salsa version of Mad Catter cheekily named Happy Catter.

At last, the meme happened as one of the final exhibition fights. I drove Overhaul while Bunny drove Sadbot. I literally bought a chair from Team Toad for $10 on the spot to use in this fight, where we set it up and I tried to drop Sadbot on it.

The handling difference between the two really motivated me to swap Overhaul to all new sensor-integrated C80s. Sadbot basically drove like it was brushed again, even if the VESCs still had infrequent (but still annoying) overcurrent faults just because of how outclassed they were by the motors. A swift return-stick-to-neutral was enough to overcome that. Overhaul, being still stuck in Sensorless BLDC mode with some tweaking, drove like an unloaded bus on ice in comparison. I had to anticipate when to turn and basically coast into it, or keep moving in one direction without direction changes.

Overhaul’s forks managed to tear up the drive on Sadbot pretty well, including bending both of the little chain-guiding nuggets and making Sadbot lose a drive side. In return, I accidentally drove the head actuator off the end of the screw trying to pick the chair back up, so Overhaul’s head came flopping downwards. Oops.

Unfortunately, the organizers had issues with the stream (found after the fact; they were thinnly manned and needed all the help they could get!) and as a result we don’t really have any good video from the event, especially the Heavyweight fights. They posted basically “raw” box feed videos at this link.

Sadbot appears in the following fights:

There are videos of the beetleweights and other weight classes on the promoter’s Youtube channel, though. Those were run in a separate arena and as a separate stream.

So I came away from Comicpalooza with a lot of good lessons learned and two working robots. Well how about that!? The real champion, though, we all know… is Your Waifu is Trash.

The lessons from this event went straight into Overhaul when I transitioned from Operation IDIocracy to Battlebots Season 7 prep. We changed all the drive motors – in-use and spares – to the sensored C80/100s, and I ordered spares of those.

I also got more VESC6 units from Trampa and set them all up in FOC mode with sensors, using one calibration/detection and propogating all the settings (The motors are all close enough together characteristics-wise that the small differences were not first-order impacts on control loop behavior). Other than that, the bot didn’t see that many changes and optimizations for Season 7. And, despite “Losing” a bunch again, I think Overhaul really had its best reliability and predictability season to date.

By the way, if the trip to Comicpalooza was comically loaded, the return trip was even funnier. I promised to bring Slammo back for Craig, so on top of all my gear, there was now a Slammo, its parts, its tools, and its handling equipment. He journeyed down from North Carolina a week or so later to collect it all.

I was surely running close to GVWR, and I got concerned enough to inflate the rear tires to 50 PSI for the return trip. I headed northwards out of Houston, taking the I-20 route back east because it turns out I-10 is just like the I-95 of the Gulf Coast: Always crowded, always jammed, always under construction, and everyone is out to kill you all of the time.

Motorama 2022: Susquehanna Boxcar and Justice for Vantruck

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On a somewhat rainy Thursday evening before the weekend of Motorama, after Susquehanna Boxcar was all put together, I began loading my Pelican cases decade-old Harbor Freight aluminum suitcases (who can afford Pelican cases??) of robot gear into Coronavan so everything was ready to hit the road in the morning. The plan was to get there over the course of Friday and unload everything so I don’t need to rush on Saturday morning, and maybe help with some setup as well.

Friday morning, I woke up and pulled everything out of it… because shit’s about to go down.

That’s it, we’re doing this now.

The last time I tried to have you do something useful, you randomly broke down on I-81 in Virginia. Vantruck had not wandered north of the Mason Dixon since the very last week of 2019. Of course, after replacing the fuel injectors and harness inside the FiTech throttle body unit, it’s been just fine for everything I’ve had it do, including pulling Murdervan, Snekvan, and several jeeps back home.

Still billowing blue smoke and missing a cylinder, but what else is new. We’re just going to dive right into this after an inspection of fluids, belts, whistles, and dingles.

But before that, over the course of the week, I was making Motorama trophies! I took on this responsibility after the original maker had Personal Problems come up. They were going to be laser cut and engraved. It just so happened in the months prior to this that I had picked up a 18×18 75W laser cutter on the cheap.

As with everything else lately, I owe a post on the process of getting that junker up and running again with replacing the tube, squaring the gantry, and so on. But, trophies.

I made a few test cuts in different colors of acrylic I had hanging around, then had the organizer order a few sheets to me through McMaster. Design three was what we ended up going with, though I personally prefer the clear plastic. The stands were already made, so I just had to supply the display panels.

asslaser69 (as it’s named in the print driver selection box) handled this first major job exceedingly well. Before this week, it had only cut random little trinkets as tests. To prepare, I bought a hydroponic weed growing aeration pump as the forced air blast source and it was running an aquarium pump submerged in a 5 gallon car wash bucket.

Look, all the pieces are there. Even if they’re wrong.

One of the upgrades I want to do eventually is a long-focus (100mm) lens and a gas lens, so it can get through some thicker stuff. It’s honestly just fine right now for basically everything you’d use a CO2 laser cutter for, but muh scope creep.

Of course, when you let me make visual products, you are going to have shit like this be part of it.

Common rule of thumb for being my co-worker: If you know, you know. If you don’t know, don’t Google it. Especially not on the lab’s network.

With Vantruck given the green light and my Extremely Large Miku print strapped in the back seat, it was time to ship off northward!

immediate regret

The journey was uneventful (good… misbehave and the methy junk man will come for you), and it was quite pleasant to be heading to a familiar haunt of mine. Motorama had been canceled for 2021, and I wasn’t in any position to turn around a trip back in 2020. I romance the I-81 corridor a little in my personal make-believe TVTropes page in my head, but it does form an axis between me and the friends and adventures I left behind up north.

It would be nice for it to hurt a little less though.

Just a little bit less, please.

Remember, this was the weekend before Russia really lit off World War III. Gas, while post-economic reopening expensive, wasn’t Summer of 2022 tier expensive. I can’t imagine making this trip at all if it was even a month later.

12 hours after leaving, I rolled into the Pennsylvania Farm Show Complex. Not a peep along the way, though the oil usage was on the order of 1/2 quart or so (Hard to tell if it’s just that I didn’t give it an hour or so to meet back at the bottom).

This should be more of a 9-10 hour trip (having made the run to Norwalk using the same route a few times) but Vantruck’s preferred speed is more 65mph instead of the 85mph+ I keep trying to pull with Coronavan.

I unloaded everything and went around to help set up the arena and said hello to everyone. But, before I could leave, I had to attend to a Vantruck thing:

It just wouldn’t be a van trip without me fixing something in the parking lot somewhere. On the way in the gates, a security guard let me know that my right side brake light was out. Odd, since I hadn’t noticed the turn signal blinker acting up. It turns out the running light filament was out, so the turn signals using the main filament would still be good. I did manage to break the bulb apart while extracting it from the socket, though.

In a stroke of … well, typical luck, someone at the event just had a few 3157 bulbs sitting in their car, and at a robot event we all have pliers and grabby tools of some sort, so this was otherwise a fast repair. Makes me wonder how long it’s been out – it was dark at least since northern Virginia, and I don’t hit the brakes on the highway. Vantrucks do not have to follow laws.

And that, kids, is how I found myself holding an inflated 6S lithium battery pack, standing in a Waffle House in Harrisburg, PA.

It’s the next morning and time to get serious. Everyone’s here now and going through inspection and testing!

Been a good long time since I’ve seen any of the bots or the builders. This is “Starfather”, a 30lber from the P1 team and the larger version of “Starchild” which is right next to it. It won’t be the last time I see this thing either.

One thing I can appreciate is that Norwalk’s multiple tournaments per year, all full-contact in nature, has really pushed the evolution of the 3lb through 30lb classes. Designs were on point this Motorama. A lot of bots were very clean and professional looking, some from builders that were just starting out with their first kitbots or 3D printed 3lbers in 2019 when NHRL really kicked off.

A small 12 pound tribute to Poison Arrow.

The rise of more on-demand machining services in the past few years has really let robot builders leverage the competitive pressure and creative use of materials/processes. It’s way easier to achieve robots that “look like a thing” nowadays – 5-10 years ago I could easily see this being a square aluminum bar frame, for example.

A Sportsman class flipper with some serious machine and welding work on it.

Hell, even bots that are “traditionally built” are on point nowadays. This thing – appropriately named Pipe Bomb – is a full body drum spinner with mostly 3D printed internals but hand-cut UHMW plastic wheels and endcaps. The giant ring bearings supporting the drum had all the grease washed out of them and replaced with some light oil for less drag. It spent much of the tournament sideways trapped on its wheel faces, but took an absolute beating and kept running.

This ultra-stanced conical wheel drive flipper named Pigeon was interesting. It let the bot be very low sloped on the sides without compromising wheel track spacing and wheelbase.

Some high quality machine work coming out of Wedge Industries (who has since stopped machining things in order to machine more epic things) this is Crunch Time, a scaled down tribute to Quantum/Spectre from Battlebots and King of Bots.

It turns out when your load case is that of a skull, it’ll generate you a skull

– alex, maybe

Told you this wasn’t the last time you’d see Starfather. It turns out that’s my first match. The only top-attack robot in the bracket and I somehow drew it, with the robot that has the most exposed shit going on up top. For giggles, I obtained a Brandon Sign from the dealer hall (this is a rural motorsports event, there is plenty of Brandon Signage) and bolted it to the Multishovel to give Brandon Zalinsky, the builder/driver, something to think about.

Well there wasn’t much thinking he had to do, because it didn’t end well for Susquehanna Boxcar. Starfather pretty much nuked everything on top. I left the arena functional, but with one dysfunctional motor and more possibly smoked, but still moving.

The weapon got in a direct hit on the pokey stick shaft, which is hollow and so folded like a lawn chair. It also nicked the sprocket and bent it sideways. This bend was unable to get straightened out and compressed again to to the point where the chain could wrap around it, so it was eventually cut out.

Starfather’s weapon also put some clean gashes into the Multishovel. Amazingly, it did not break off its mount, but just backed the locking collar off its thread.

The most important damage was to the drive motor, where it cleaved through the UHMW mount and completely broke (and bent) the motor. I only had 1 spare 555 mild-wound motor with me, and it was going to replace this one. The other three motors all smelled kind of interesting too, so they were not long for the world.

My next matchup was against Pigeon – the ultra-stanced face-wheel drive flipper seen above. This was a pushing match that I could not win, so I just drove around to the best of Boxcar’s ability. No damage sustained in this fight, but between the 4 drive motors I think I had 2.5 left by the end.

The next day, I stopped by the local Asian grocery tore to pick up some snacks and a new weapon for it since I was planning to enter as many rumbles as I could:

Nicknamed “Danger Potato”, it was a taro root that we impaled on the end of one of the pokey-sticks and wrapped in caution tape to prevent it from coming apart.

Danger Potato in action in the 30lb rumble (Starting at 04:38:40 or thereabouts, if the time link doesn’t work). I basically ran around like a dumbass until the motors all smoked, and then just sort of flailed around.

So what lessons have I learned from Susquehanna Boxcar? Nothing. It served its purpose beautifully: Be basically free to build and be an entertaining meme. The mild-wound 550 printer motors were a bit of a wash, but I knew that going in. I’ll definitely just change them to some equivalently-powered brushless motors and bring it back next year. The top side could use some work, but hey, it’s all stuff I found in piles in the garage. The drivetrain itself took no damage, nor did the internals beyond the chunk taken out by Starfather.

This was a nice break from van-related work and reminded me that robots can still be fun. Between BattleBots and having to take myself seriously, and NHRL’s focus on the prize, robots have more and more seemed like a chore as of late. Honestly, besides this coming BattleBots 2022 season, I think I’ll only stick to Sportsman-ish events like Motorama 30lbers and Dragon Con from here on.

After everything was wrapped up and done, I was presented with a prize for Vantruck. The Jeep Bros that I keep fetching wreckage in Alabama sheds for found this pickup truck roof wing at an estate auction. I’ve been looking for something like this for a good while since buying new ones is expensive, and mildly considered building my own.

Largely just to completely The Look – it’s not like I will ever regularly tow a Portable Convention Center & Hotel which could use a forward-mounted wind deflector.

Of course, it wasn’t time to go home quite yet. In another “This isn’t a van trip without fixing something in the parking lot”, early on Sunday morning I went to pick up a part that I suspected was giving me some trouble on the way up, and definitely confirmed it once I arrived.

That’s the mechanical, viscous-coupling fan clutch at the front of the engine. I began to suspect it had seized up because during the trip northward, as temperatures fell, I noticed the coolant temperature never going above 150-160 degrees, dropping some times as low as 145 degrees.

140 degrees is the threshold for the FiTech control unit going back into warmup mode. The fuel mixture became richer, and my gas mileage dipped to even more horrifying levels. If the fan clutch seizes, then the engine fan will always be turning and therefore overcooling significantly in the cold winter night air at highway speed.

This was a quick enough fix, and I could reach in behind the radiator to undo the fan hub nuts, then unbolt the fan from the clutch.

I finished this in about 15 minutes in the Motorama back parking lot, and as you’d expect of a gearhead motorsports event, about a dozen people stopped by to ask if I needed help or supplies. I’m sure I’m far from the only one trying to resuscitate a patient on the ground here. After installation, I caught up with some people for dinner and started bombing it southbound…

Only to encounter more pain I stopped for the night near Roanoke, VA and continued Monday morning on a little detour.

Alright, I’m conveniently positioned to cross the Blue Ridge and Smokies at some point, and somebody hasn’t been back here since Dragon Con 2019. So we know what this means…

It was a very quiet morning on the Tail of the Dragon. Being in the middle of winter, the resorts were all shut down and the photographers were not out in force (though you can still beckon and commission them for a fee, ahead of time, if you so desired), and I took my time with the mountain crossing.

In all, the trip was completely reasonable (for me, anyway – reasonable implies at least one or two wrenching oopsie moments are designed in from the start) and it was a good way to recast a hobby that had, in recent days, felt more like an unpaid internship *ahem* Battlebots than bashing it up with friends and onlookers.

From my return, I focused more on getting the 7.3 IDI engine from Snekvan rebuilt; it had already been extracted from the van by New Year’s Day 2022 and I was halfway into tearing it all apart. I had an eye for getting Vantruck swapped and ready for Dragon Con 2022; this also means I’m like 11 Operation IDIocracy posts behind.