Archive for January, 2017

 

Shut Up about “Modern Technologies in Robot Fighting” Already: A Charles Editorial

Jan 20, 2017 in Bots

So I very rarely go off on polemics on this website. In fact, I can’t recall the last time I straight up roasted something, besides laying on Sparkfun periodically for getting their breakout boards amateurishly wrong, or complaining about literally everyone else’s motor controllers. I try to stay focused on relaying the technical and weaving tales of implementation while discussing mistakes and could-have-beens, because I enjoy clearing up the fog of knowledge when it comes to building. Not only do I like making my work accessible, but I hope every motor controller I blow up also creates a record of what kind of REALLY? IT WAS THAT? mistake the problem ended up being. It’s always that.

A little to this end is my tendency to never claim I know something that I actually don’t. I hope I’ve been pretty good at keeping to this philosophy, and you’ll notice in many posts that I tend to express uncertainty when explaining a problem because I don’t know everything about it at the time, and the reasoning will probably change later. Furthermore, as you doubtlessly know already if you’ve been on the Internet more than an hour, the quickest way to get correct information on the Internet – whether you like it or not – is to be publicly wrong about it.

This is a double-edged sword; I’ve wielded it cloak and dagger to get correct information from enthusiast groups & forums of technical discussion before, and it works great! Try it some time… just say something nitpickingly wrong, such as “You can totally use frequency-injection rotor saliency detection on surface permanent magnet motors with an Arduino!” and someone will be bound to reply “Well technically, it depends on your stator saturation model“.

Well Technically is the zip ties and duct tape of unsound technical reasoning – collect enough Well Technicallies and any poorly-founded conjecture will stand up on its own, suspended by the tensegrity of vague wording and handwaved speculation.

If you didn’t understand what the hell that example meant, don’t worry – I didn’t either. That’s why it’s nitpickingly wrong.

On the other side, relaying incorrect or incomplete information opens yourself to being called the fuck out, which is what I intend to do. So let me begin with

Stop. Talking. About how every problem in the robot fighting world will be solved by the Inter-fucking-net of Things. Or how builders should just try smartphone control already. Why don’t we all use DEEP LEARNING to strategize matches in realtime? Just shut up and build your first kit antweight.

It seems like every few months, someone on a public robot fighting related forum will make a contentious point about how NOBODY USES WIFI TO CONTROL THEIR ROBOTS? WHY? or champions the favorable characteristics of switched-reluctance motors which they learned about on Youtube approximately one millennial attention-span ago (Oh shit, I made a millennial joke! Is this self-deprecating humor or am I just a lawn security officer now?!). I regularly have people ask me why nobody uses Swerve Drives when all the high schooler robots do it already. With near certainty the poster is pretentiously tech-savvy about the Connected World or is an Internet of Things developer who probably has an Amazon Echo bickering with a Google Home about control of the sex lighting in the basement, ON YOUTUBE.

AND WHAT ABOUT  D R O N E S ?

Robin Mitchell of Allaboutcircuits, I am now talking directly to you. In your recent article “The Resurgence of BattleBots and Robot Wars“, you put forth such affronts as “…the new Battlebot and Robot Wars series showed little technological advancement with regards to sensors, microcontrollers, and electronic warfare.” and propositions such as “…use multiple relays that isolate separate batteries from the robot which can be switched on and off using the main controller.”

Hang on a second – let me go find a “relay” that is rated for the combined current draw of all of Overhaul’s drive motors. Want to see what it looks like? This is it:

When they get that big, they’re called “contactors”, but that is besides the point; I’ll get to reasons why automatic power failover is a nice thing but (to my knowledge) completely unseen in robot combat.

Let me be clear here – I have no personal grudge against you, Robin, nor do I have a problem with Allaboutcircuits, a site that I used to reference daily years ago and should continue making a habit of. If you’ve never built and fought robots, it’s a perfectly excusable pass on the misinformation front. Everything you presented can technically be achieved and could possibly be used productively in robot combat. However, recall the 2nd part of my thesis regarding being wrong on the internet: this article is also epitomic of all of my presented complaints about outsiders observing the “technology” in combat robots and snidely commenting on it, so I feel implored to reply.

1. On the structure of precision language

One of the hallmarks of technical misinformation is nebulous & vague wording that sounds good to the casual onlooker, but sooner or later you’ll run into someone who actually know what the hell they’re talking about. The article is absolutely infested with these missteps, starting from the very beginning about rapid prototyping.

No, rapid prototyping is not JUST 3D-printing. Rapid Prototyping is a set of techniques – of which 3D printing is just one – which ideally help you reduce the time and effort needed to produce working products or concepts thereof. Though everything I do can technically (there’s that word again) be construed as rapid prototyping, nothing about Rapid Prototyping must involve a computer or a poorly-built kit noodle-pooper.

In modern parlance it is often assumed to mean the same as digital fabrication, which 3D Printing is most definitely a part of: computer-controlled machines which generally perform one task whether it be machining or extruding or lasering the ever-loving shit out of something, which can be quickly set up (rapid) for the creation of objects (prototyping!) more or less directly from a digital design file.

Now, what does this have to do with robots? Rapid prototyping techniques (plug!) and equipment have contributed to a vast paradigm shift  in how small and large class entries alike are built, and despite not being very visible on the BattleBots TV show, a significant number of entries had 3D-printed parts inside. Hell, I’m one of the two teams sponsored by MarkForged, a 3D printer company which is on the intermolecular-bond-splitting edge of 3D printed material properties.  You can also barely find a 150 gram to 3lb (“insects” class) bot these days which doesn’t have some kind of 3D printed artifact on it, possibly even entire frames and even including weaponry in the new “Plastic Ants” class.

The newest “easy way” for builders to start is no longer piecing together R/C cars with Home Depot sheet metal, but grabbing a 3D printer. That is huge. The first moment I ever felt old was the first time I was casually talking to a freshman in the fab shop that I ran at MIT and the subject of building a 3D printer just casually came up as “Oh yeah I built one of those in high school”. Bam, just like that, I officially entered intellectual cruftdom, the derpy 80s prismatic van state of epistemological being.

Beyond the limited definition of 3D printing, you have robots utilizing laser-cut steel unibodies that are ordered direct from a steel vendor by sending them CAD files and pieced together in just hours with a welder, bypassing dozens if not hundreds of man-hours of shaping metal, fitting it together, jigging it all up for welding, and then doing the welding. Every curvy or fancy looking robot exterior on the most recent show was likely not trimmed by hand, but waterjet- or laser-cut in minutes. That is the real magic of RP techniques in robot building, and I do think a lot of the current “innovators” in this realm are recent college grads & young professionals who have seen the techniques used elsewhere and brought it to the forefront in the sport.

Besides painting ideas in broad strokes, there is also a tendency by Modern Technology people to speak generally of executions, never having to have executed them or thought about what their ideas really entail. Going back to the relay problem, the solution (to a problem I contend does not actually exist) is:

One possible method is to use multiple relays that isolate separate batteries from the robot which can be switched on and off using the main controller.

Soooo…. does that mean making a battery isolation system out of relays? They sell devices for that, often for RVs and boats with multiple batteries. Either solution (neglecting the practicality of a 3rd or nth power source exclusively for the logic) means you need “relays” that can each take the full operating current of the bot, and I showed you how big that part is. Wait – no, back up. Before we even reach that, this implies you already have multiple batteries each capable of running the bot separately for the duration of the match, unless you size them to require mid-fight changeover.

Imagine if Tombstone had 3x the number of batteries it actually needed to run a match. That would be a riot! Good luck designing this system within the weight limit while still maximizing your robot’s operational ability! Lithium polymer batteries be magic, but they’re not that magic just yet.

On top of that, you have things like

The communication system could also be improved in many other ways including the use of a microcontroller instead of using an RC module with outputs that connect to actuators and subsystems.

Okay… yo, what does this even mean? You know all R/C receivers have microcontrollers in them, right? And every motor controller? If you don’t have an R/C module (which I guarantee the author doesn’t know is a real, commonly used, and nice thing that goes into your handheld transmitter  – Overhaul uses a 400mhz Long Range module system that can conceivably let me control the bot from over 10 miles away)  what does your microcontroller use to talk to your smart watch and smart dildo that you’re using as a robot control input?

If a player switched to 2.4GHz and used a module like the ESP8266 then…”

INTERNET OF THINGS BRO DETECTED! You’d swear with the number of people singing the gospel of the ESP82x system that it will singlehandedly stop Russia from starting Cold War 2: Thermonuclear Boogaloo on the 20th here or something.

(Nevermind the fact that the preceding sentence to this misplaced quote “The radio frequency that these robots use will most likely be around the 27MHz channel” is absolutely, indisputably incorrect, as 27mhz has been banned in most larger weight classes since the late 1990s and prior to the rise of 2.4G spread-spectrum hobby radios in the mid 2000s, most robots were mandated to run on 75mhz using compterized PCM transmitters. This is just being factually wrong instead of spiritually wrong.)

Anyways, in this case, I assume what’s going on is another case of hipster engineering colloquialism – when certain people say microcontroller what they mean is an Arduino. Yes, a separate microcontroller can be used to collect all of the information proposed – voltages, currents, temperatures, etc. Again, there’s that Well Technically factor: Yes, you could collect all of this data, and yes, you could transmit it over WiFi to an iPad set up with a custom dashboard app you wrote, but all of the data in the world about your CO2 tank upstream pressure doesn’t help you when the tank has been eviscerated and unceremoniously thrown across the arena by Minotaur.

Having these onboard sensors does not inherently make the robot better at robotting. It’s like having the same telemetry in a car – it will help you potentially tune the car for performance, but does not alone make it faster. This information could very well help you discover a design issue with the robot – motors drawing too much current and heating up too quickly? One weak battery out of four? Better take care of those before you run out of postponements! Telemetry and “sensors” comes up a lot – likely because people who keep ragging on this are IoT bros – and the praise of Team Storm in the opening for adding sensors to their old and tired design to instantly make it modern , parallel to the phrasing of robots being “improved” by sensors, is a good example of my second thematic struggle with futurists in the robot world, which is:

2. On optimality of cross-discipline solutions

I don’t blame people for talking about automatic battery-switching failure detectors or first-person view cameras with dynamic robot-to-field orientation control or any of that. The fact of the matter is, they could be speaking from experience (or out their ass) in a field where such things are common and expected – automatic failover is virtually required in server power supplies (and the servers themselves in modern datacenters). FPV is increasing in popularity within the vaping rig drone community because flying a drone while “sitting in it” can be very intuitive, more so than trying to stare at it from 1000 feet away.

It is the insistence that their favorite golden engineering goose will equally lay golden eggs across all fields, without any relevant experience to back up the fact, which I am considering here – the insidiousness of Well Technically is at play once more. Again, I don’t care so much about being straight-up factually incorrect, because that’s easy to fix.

Remember the Reddit thread I linked to at the beginning. If you haven’t Reddit, the gist of it went something like:

Well, robot builders don’t like new things like WiFi – look how long it took them to use 2.4Ghz radios!

That’s because most R/C 2.4ghz systems for sale did not meet robot-specific needs, but now they do.

…But robot builders definitely don’t like new things, look at how few people use brushless motors, everything uses brushless motors!

That’s because most brushless systems for sale did not meet robot-specific needs, and still kind of don’t.

WELL GEE I THOUGHT THIS SPORT WAS ABOUT TRYING NEW THINGS

Let’s talk more about swerve drives. Swerve drive, bro! Holonomic motion, bro! Got 8 degrees of freedom on my drivetrain, bro! Any direction, any time, bro! My conversations with what must be the closest thing to the Jehovah’s Witnesses of robotics because they will never, ever shut up about DO YOU HAVE A MOMENT TO TALK ABOUT OUR LORD AND SAVIOUR TEAM 221swerve drives once they find out I build combat robots consistently goes something like:

Do any battlebots [with a lower-case B, this is important] use swerve drives?

Not any current ones, only a few have tried in the past, but none have been successful.

Oh, that’s weird. They’re the best drivetrain for this kind of stuff.

Why do you say that?

You can move and attack from any direction!

You certainly could, but durability due to the increased mechanical complexity is a concern, as well as added weight.

Well you just have to { CNC machine all of the parts from titanium, use this design I found on ChiefDelphi, place them closer to the center of the robot and armor around them };

Additionally, not many weapons and strategies can take full advantage of omnidirectional motion. It all comes down to design compromise and what you want from your robot.

Well you can just…

Those choices in brackets? I’ve personally had to absorb and nod my head to each of them. My most memerable instance involved someone literally following me for 10 minutes describing how if the robot just had 4 flipping arms, one on each side, then it would be a good use of swerve drive because it would be universally defended.

JUST.

That word is like the dual of Well Technically, like the superhero and supervillain comic story of Half-Baked Idea City. For every Well Technically rebuttal, there is a Just conjecture.

Now hang on a minute here… If your robot already has weapons on every side, does it really need omnidirectional motion at that point!?

All of this might sound like I am the sheriff of the GET OFF MY LAWN police force. And you know what – maybe I am a rookie officer in training, having been in the game for too long and the ‘stock solutions’ for common strategic problems having calcified in my design process. But let me be clear here: What really Brinells my bearing races is not that people want to try to build Cloud-powered Robots-as-a-Service, but that they immediately pose it as the best possible solution to a problem they otherwise profess ignorance to. It’s not that you can’t use ESP8266 modules in your custom radio, but the coming right out guns-ablaze and saying that it is better than R/C radios. Better in what way, being easily customizable beyond user comprehension in an application where communication errors can result (and have resulted) in the runaway of a machine literally designed to kill the fuck out of other machines? It’s not that swerve drives have never been used in BattleBots (we don’t talk about Radioactive), but it is always presented as inherently better than tank-style steering, despite the added moving parts that must remain in close alignment to work properly, because in combat robotics all of your parts always stay aligned!

What these examples have in common is that people will take their knowledge of something which has an apex predator status in their field of work (or interest) and assume that it would work just as well in another context, change be damned. Robot fighting, truth be told, is a pretty damn redneck sport in the grand scheme of technological competitions. Nothing that relies on banging two objects into eachother really hard for entertaniment can be that refined, right? We are, in some sense, a bloodsport of technology. That has historically made robot fighting easy to talk down to by people working in technological industries, especially software and AI. Add to this most bot builders being in the mechancal engineering or machining/fabrication industries, or simply being mechanically inclined, and you have a perfect fuck-shit-stack of lost-in-translation: The finery of the often extensive mechanical design work and manufacturing effort being unappreciated by someone who’s never picked up a tool, and the perception of sophistication they associate with their choice of career, or their preference of controls and intelligence complexity.

The person who followed me around the building trying to convince me that swerve drives were the Alpha and Omega of robotic drive solutions? I challenged him to build a scale model of his concept robot in any weight class, and that I would permit full normal usage of my shop for the purpose and make myself available for consultation. Never heard a peep from him since.

Don’t be that guy. If you want to explore “smartening up” the sport, do so and deliver. Probably the most under-stated thing at BattleBots Season 2 was the auto-targeting hammer of Chomp, and it’s a shame they devoted only like 3 sentences on the show to it. Very few people have ever attempted auto-firing or target-seeking weapons. They knew it was a huge risk and that it might not work, but GOD DAMN IT WAS DELIVERED. I like to think that I pushed the front of using hobby-class brushless gear in robot drives with my 6-month-long development cycle and immense risktaking getting Overhaul 2 into the arena with all HobbyKing motors and controllers. The evolution of technology in robot fighting is truly, and some times literally, trial-by-fire.

Go to a competition and learn what kind of details you might have missed while perfecting your off-the-wall design concept; enter a kit antweight and get your ass handed to you in a match to see how hard it is to maintain an entry. Then build your gesture-controlled SLAM-navigated swerve-drive Hoverboard-motored* Internet-of-Things-connected self-Tweeting BattleBot. The whole sport would appreciate your contribution, even if it gets turned off at 0:11 by an errant power-handling relay.

*I challenged myself after talking to the High Priest of Swerve Drives to design a swerve-module which could conceivably drive a 250lb Battlebot and not weigh much more than a typical drivetrain does, while being heavy duty. This actually is possible, as illustrated by DeathRoll during Season2; it had four seg-thing motors running at 36V each and was pretty maneuverable. The module ended up weighing around 25 pounds, and used a A23-150 Ampflow motor for steering. Four of these would weigh about 100 pounds, so it could happen, but would need tight integration into the frame design to have weight for anything else like weaponry.

The Chronicles of Vantruck 2: Not-Yet-Electric Boogaloo

Jan 12, 2017 in mikuvan, vantruck

sigh

It’s a new year, and somehow I’m outside, in the middle of winter in Massachusetts, at night, fixing a van.

Again.

As I’ve said before, imagine if I ever exert this much effort doing something socially beneficial or self-improving.

I’ve been sparse lately, though, due to a similar kind of exertion that is called “working for yourself”. When you’re me and you take contracting work, you begin to adopt everyone else’s malformed, premature project embryos as your own, and raise them until they can walk on their own, often into a wall. The upside is that I can pick my battles and choose my projects, but the caveat is that I was never good at time management anyway, so it’s sort of easy for me to get lost in work. Overhaul has been living under a table and Clocker 4 hasn’t been repaired from Franklin Institute yet. Please make #season3 happen ):

I am, however, signed up for Motorama again, and you know what this means:


WE MEET AGAIN

 

This time, I will be unstoppable. I will be a worthy opponent!

But first, to get to that point, Vantruck has to be legal to operate in the state of Massachusetts, among other things. So time to get to work!

I have a habit of buying something and then doing research on what it is I just bought. This is why targeted internet advertising never works on me, because it’s too late to show me Ford truck ads now, guys.

To this end, I went ahead and picked up a copy of both the Chilton’s and Haynes service manuals, as well as copy of the Official Ford E/F-150-350 + Bronco Player’s Guide on CD, since I like information. Also, I’ve otherwise never owned a vehicle that had been worth writing an aftermarket service manual over. When one book can cover almost 30 years of one model, or SEVEN MODELS AT ONCE, that’s when you know that 1. it’s good, and 2. it’s why we need globalized diverified economies.

Okay, I’ll take number 1 back. These manuals suck. They’re definitely very “old school car guy” centric, but perhaps it’s just the ones written for old vehicles. The section on how to rebuild your carburetor or adjust the bands in the automatic transmission? Awesome! Checking all engine bearing, cam, and valve clearances? HUGE!

Electrical?

YES, THERE ARE WIRES (1978 F-150 W/ 6-302 ENGINE SHOWN; OTHER MODELS SIMILAR)

I’ll be up front, the only thing I know about carburetors is that a unicorn lives in each barrel and it decides how much fuel to mix with the incoming air. Vantruck’s Ford 460 engine has a 4-barrel carburetor, meaning it has 4 unicorn-power. At least 1 of those unicorns is slacking off when it gets below about 30 degrees, since it will only hold idle with a little bit of throttle application for a minute or so until it warms up. I am told the unicorn has to be choked to whip it back into shape, and the mechanism that does this might be sticky.

Whatever. I don’t care about carburetors. Maybe one day in the future I’ll write the Haynes manual on how to rebalance your future solar-powered bubblecopter’s main lift motors in excruiciating detail and some young hotshot will tell me that nobody uses electric motors any more and that all new bubblecopters manipulate the electroweak force to spontaneously decompose atoms in front of where you want the propellers to be.

So let’s see what I’m dealing with here…. Remember, the goal is to get turn signals and reversing lights working again!

Alright, so the circuit I’m interested in is protected by Fuse 10. I confirmed that yes, no matter how big a fuse I put in, it immediately blows on any turn of the key, so it’s a hard short to ground somewhere. Referring to the wiring diagrams in the manuals (which all say the same thing in slightly different line widths and wiring label mnemonics), I see that there is a combination switch on the transmission that directly controls the reversing lights.

Given that the hazard flasher still works, and the turn signals do flash with them, I suspected a hard short somewhere along the body harness for the reversing lights. The turn signals are on a different path and therefore not affected by the short, but it will blow the fuse and cause power loss to both.

Interesting fact: No matter how large the nose on a full-size American van, there is still an access port for the engine on the inside, and it’s the same for Chevy/GMC and Dodge too. This thing really has less lateral legroom than Mikuvan does, and it’s because the engine is slightly ahead of you, not slightly behind. You’re still basically sitting on top of it.

Why can’t you be a 1960s Econoline instead? They even made pre-truckified versions!

Here I am popping the doghouse off to inspect the wiring harness going to the transmission switch.

 

And I find the culprit immediately: A very fried and rotted wiring connector and harness that was touching the engine block. It seems to have been routed in the valley of the engine next to one of the cylinder heads – so I can only surmise that it’s gotten very hot, accelerating the decay of the legendary 80s US-made plastics. This connector shell basically turned to dust when I tried to open it, and the wiring insulation flaked off in large pieces.

 

Yeah, I picked the scab for a few minutes and separated the wires where they were exposed in order to make sure nothing was shorting,  I cut the harness wrap another few inches in both directions to look for additional shorted locations, but this was the only one.

And here we go – turn signals are back!

However, there were still no reversing lights. I metered the circuits and discovered the transmission switch’s reverse position had failed open – perhaps due to the shorted harness. So that’s a few bucks on eBay for another transmission switch!

Meanwhile, I moved onto excavating other wiring artifacts, playing such games as “Where the hell does this bare-ass connector go?”

I couldn’t find any mating end for this bare terminal; it’s on the same circuit as the power supplied to the transmission switch and is allegedly part of the ignition interlock (for no starting in-gear), but I can find no mention of it anywhere in the manuals – probably an aftermarket mod that was later removed. I taped it off for the time being.

Then we have this rare example of an American Wiring Kudzu:

Someone please tell me this is not OEM. Compared to Mikuvan’s “all in one extravaganza” wiring experience, this is borderline unreal.

I couldn’t identify what the leftmost and uppermost components (with rusty terminals) were, but one of the right hand side relays seemed to be a headlight relay and the other one a horn relay. If you know what those other things are, please let ME know. I just wire-brushed and dielectric-greased the terminals and called it a day.

Following the horn relay caused me to discover a very long-dead airhorn compressor buried near the front radiator supports. Since the plumbing seems to be in place, maybe I’ll try hooking up a new airhorn compressor at some point…

Flash forward a week and the new transmission switch has arrived. This is a photo of removing the old one – it was a very straightforward procedure, and I actually did it “by the book” as recommended.

Interesting fact: The orange tube seen in the first ‘doghouse’ photo is actually a linkage that connects the throttle body to a small lever on the transmission selector valve. Its termination is shown here. Not only is it actually a linkage, but it’s actually the connecting link in a 3-dimenional 4-bar linkage and moves in a circular arc centered somewhere inside the engine. It’s the transmission kickdown linkage, and when you hit the gas pedal hard enough, it moves outwards at the throttle body, translating through that circular motion into a downward motion at the switch here.

It doesn’t stop there; EVERYTHING IS LINKAGES. The throttle itself is a linkage, and the main gear shift selection lever also toggles the leftmost brown bar as a linkage. The parking brake linkage seems to move on the same set of pins this whole clusterfuck moves on, connected to the frame.  AND EVERY ONE OF THESE LINKAGES IS SLOPPY.

I legitimately don’t know if I should be horrified that someone thought this was a good idea, or amazed at the ingenuity that went into packaging everything.

Whatever. You’re all leaving for a sack of electrons in the next few years. I cleaned up the area and regreased all the pins and clevises for now. I should just pack everything with JB-weld so it fills the slop!

As the first wiring repair a few days later, I started with the most critical issue, the transmission harness. Here it is repaired with a few more inches to spare ; this extra length will let me route it up and over the hot part of the engine, over the air cleaner lid, and back down towards the transmission.

Alright, with my turn signals back on and the reversing light circuit showing continuity, I still had no reversing lights. Well, time to go see what other wires could be broken. The wire emerging from the transmission switch which allegedly goes straight backwards to the reversing lamps did not show continuity to ground, meaning it was broken somewhere along the way. First, I checked the light modules themselves, which meant starting at the back…

Bad mistake.

Judging by the aging of the various nylon splice connectors AND A WIRE NUT. WHO THE HELL USES WIRE NUTS HERE I think at least 2 jackasses have been here before me, making me the third ass. Several aftermarket trailer devices have probably lived and died here, and there were not only stubs of wires (some of which I might need) but splices like this rare Shadtree Wiring Octopus living in the back bumper area.

Speaking of trailer accessories, here’s a quick side story.

Since the beginning, Vantruck has had a magic switch installed on the underside of the dashboard. Neither the seller nor I nor my truck-buddy Dan who I blame for this whole thing could tell what it did, or where it led.  This magic switch had a yellow and a brown wire coming off it, with the yellow going directly to 12 volts at the fuse box. The brown wire, though, disappeared into the abyss.

As long as I had the dash and other panels off hunting for the transmission switch wiring, I decided to follow the brown wire.

From the switch, it runs downwards and follows the rest of the body harness out to the front driver’s side of the engine compartment. It’s definitely aftermarket, since it’s just stuffed into the bushing there, not part of any wrapped bundles.

Inside the engine compartment by the front left wheelwell, it makes a U-turn and dives under the frame. It runs allllllll the way back to just ahead of the rear axle, upon which it terminates in….

 

NOTHING

That was….. anticlimactic.

Oh well. I ripped this wire all the way out, along with the entire magic switch, and some of the wiring stock ended up making it back in the form of taillights.

At this point, I looked up and discovered this creative arrangement of fuel lines and seemingly a vestigial fuel-system switching valve. The seller had made it clear that the dual tank system doesn’t work. There is another switching valve to the right, a few feet closer to the front driver’s side, which is about equally disconnected.

Since it’s silly to have such a huge truck with less range than a Tesla Model S, this fuel system will be the focus of my next adventures. I’m just going to replumb everything from scratch – I don’t even care to detangle this right now. More importantly though, the fuel gauge sensor is faulty in the rear tank (left) and of unknown vintage on the front tank (right), so they are a higher priority than being able to cause 2 forms of global warming at the flick of a switch.

 

By the way, the yellow end of the magic switch ended in a wire nut by the fuse panel, which has a connection via a 30 amp fuse to….

…a wrapped bundle somewhere in the body harness again.

You know what, fuck it, I quit. I just removed all of the splices, trimmed the unknown broken wires, and put it back together.  Currently, power windows only work if I alligator clip the door harness to 12V, so I’m pretty sure one of these things actually went to them, in defiance of the manual telling me what color wires are supposed to do what. I’ll address this later…

Since I had to get access to the rear wiring anyway for the lights, and it hadn’t gotten that cold out yet, I decided to rust-treat the rear bumper’s inside cavities while it was off.

This thing was unexpectedly heavy. It’s made of mostly 1/8″ and 3/16″ steel with stamped brackets holding it to the frame with 5/8″ bolts.  I keep forgetting that I am working in a realm where everything was designed by and for much larger and manlier men than myself.  This is good – it keeps me on my toes, and makes it even weirder to everyone else around when I pop out of it at Motorama.

The treatment consisted of a wire brushing and air-blasting the rust powder off, then treating the remnant surface rust with converter, and a few layers of clearcoat over it once it dried. Probably overkill for surface rust on the stern of the Titanic, but hey, it’s iceberg season and I had work to do while the substances dried.

Getting it back on again was an even more hilarious adventure. dem gainz

Long story short, I basically rebuilt the rear harness using the shop books as a guide. I removed several ill-conceived marker lights, seen as shadows above the wiring loop. Clown #1 or #2 had just drilled a tiny hole through the sheet metal and shoved the wire through, un-bushed and liable to being torn on any one of those holes. I’ll do my own marker lights later if I feel like adding to the already gargantuan collection of LOOK AT ME I’M A TRUCK lights present.

Finally, after shaving most of the yaks living in this region, I pulled out the taillight modules and began playing hunt the wire. Here is another Shadetree Wiring Octopus habitat. The sheer number of splices on this length alone are mind-boggling, and make me suspect the taillights are not original.  I played a game of alligator clips trying to find out what was supposed to go to where – at this point, none of the colors lined up with the shop book, so I only had intuition to help along.

And an hour or so later, the corrected harness with rebuilt areas and 99% less splices emerges.

Luckily, the other side was actually in good shape, but this was the master side where the brake light, turn signal, and reversing light body harness came in, so it was the side which mattered. Everything was e-taped together, bundled, and shoved back in.

And there we go!

Those are some bright taillights… In fact, they’re the same ones I use on Mikuvan, the so-called 10W LED “buttheadlights”.

I discovered that beyond just hacking up the wiring, Clowns #1 or #2 had in fact installed the entire wrong bulb into the right side reversing light. They somehow stuffed a type 1157 dual-filament bulb into the socket for an 1156. Nothing made contact, and so that light didn’t work initially.

Not having direct replacements for the type 1156, I suddenly remembered I bought like 3 packs of those LED things and decided to just switch over right now to LEDs. I did not have 1157s for the taillights in LED, though, so that will come another day.

These are the “buttheadlights” in question, and I can vouch for their niceness.

Buttoned back up!

The story doesn’t end there, however. As long as there was a gaping hole in the fender, I couldn’t get an inspection sticker to be fully road-legal. At this point, I had plotted and schemed for 3 weeks on how to fix the hole, but the weather no longer permitted any outdoor work that involved curing or drying anything – and I did not have any place left to pull it indoors.  I finally decided to throw it in and took Vantruck to Richie’s Automotive in Waltham, a shop highly recommended by Dan which dealt a lot with trucks. This timed well with a spontaneous New Years trip to Atlanta, so I was able to leave it there and ask for the Have At It treatment.

And here we go! After I returned from driving vans for 3,000 miles, I was totally done with vans, so Dan got the privilege of piloting the battleship back to port. The fender patch is backed with sheet metal and all the damaged brackets were also repaired; I also had them go ahead and replace the exhaust system from the Y-pipe back since it had substantial rust holes in the muffler and other spots.

So that’s why it was so loud. I thought large American V8s just sounded like that all the time.

Finally, they threw in repairing all of the marker and trim lights, including all the little ones in the running boards which were out and I didn’t care enough to do with the other wiring, as well as the ones eviscerated from the fender. It’s great to have a shop well-connected to the industry, since I am definitely not knowledgeable on Giant American Truck things.

The current outlook is to replace the malfunctioning fuel gauge in the rear tank, which reads half when full and empty when about 5 gallons down out of 22, so it’s not helpful at all. I’m perfectly content having only about 250 miles of range on one tank, since that places it on the same refueling interval as Mikuvan. I’m therefore not inclined to actually repair the fuel tank switching valve system, but maybe just join the two tanks at the bottom with a hose or a transfer pump so I have use of both tanks, just not alternately.

After all, if I make it too good, I might be inclined to keep everything running…

In other exciting van news, however, this latest trip to Atlanta did result in Mikuvan rolling the grand ol’ 200K, in the most unromantic possible location: A few hundred feet from the entrance of the Merritt Parkway in Connecticut.

Hopefully I’ll captain this Space Battlevan-ship for many more parsecs to come. I’m eager for the weather to improve again so I can continue preparing it for the inevitable decals.