Journal Entry #36

First things first. Before I start fabricating components physically, I need to build a complete digital version of Mariimo in the computer. I’ll need to build her twice, in a way.

The reasons for this are twofold. First, it’ll help me work out any kinks in her design while they’re still easy to correct. Adjustments are a fairly straightforward process when the parts don’t actually exist in physical space yet.

Second, a digital model is the first step in machining and milling physical components, which will be a significant part of my manufacturing process. In fact, once you have a finalized 3D model to feed into the CNC milling machine, it’s pretty smooth sailing from that point on. The machine takes care of most of the dirty work.

I’ll be using plenty of prefabricated components as well, which I’ll have to start ordering fairly soon if I want to avoid significant interruptions in my workflow.

Journal Entry #37

It just occurred to me that anyone who happens to be reading this might be wondering where an unknown roboticist with little business interest and no academic connections managed to acquire the manufacturing capability to create a machine of this complexity.

The simple answer is that I didn’t. My parents did. My parents owned a large robotics firm that specialized in advanced assembly line automation. The company is still around. In fact, it’s only grown larger in the years since they passed away. My parents stipulated in their will that a fixed percentage of company profits would be allocated as an allowance for their daughter, meaning me, for as long as the firm remains in operation.

I have no say in the management of the company, which is fine by me. I’m not particularly business-minded. I also have no access to company resources, which might have come in handy, but I digress.

What I do have access to is the family home, and by extension the private prototyping lab contained therein. As an only child, it was left to me and me alone. My parents used it to develop proprietary technologies for their business, in a bid to remain competitive. It contains just about everything a person could possibly need to fabricate sophisticated and intricate machinery.

Nowadays it’s simply a place for me to tinker my life away.

Journal Entry #38

So, it turns out that a person can’t just order individual smartphone components. Apparently they only sell them via enormous bulk orders intended for manufacturing giants. Not exactly feasible for a tinkerer working out of her home.

This is a problem, as I designed Mariimo under the assumption that I’d have easy access to powerful and compact mobile microprocessors. Her faceplate simply isn’t spacious enough to house standard PC components.

Not all is lost, however. I’ve made a bulk order containing about a dozen top-of-the-line refurbished smartphones, in hopes that I can strip them down and cannibalize the parts. They can keep me from buying their chips, but they can’t keep me from tearing apart their phones.

Journal Entry #39

The smartphones arrived the other day. They really don’t want you taking these things apart. I suppose it makes business sense to keep people from repairing or modifying their devices, but from an ethical and educational standpoint it’s a pretty garbage thing to do.

The process of disassembling a smartphone is needlessly convoluted. It involves heat pads, heat guns, picks, suction cups, booby traps, proprietary screw heads... it’s absurd.

I didn’t let it get to me, though. All in all I managed to salvage two matching twelve-megapixel cameras, an accelerometer, and twelve fully intact octa-core processors along with their associated RAM. Eventually all of these components will be rearranged onto a custom motherboard, creating a sort of low-key supercomputer.

Journal Entry #40

I received another package in the mail today. This one was full of sensors that I knew I wouldn’t be able to strip from the smartphones. I managed to get my hands on the heat sensor I needed for her air compressor, as well as upwards of fifty digital encoders. She’s going to have quite a few points of articulation to keep track of.

I’m just going to start setting the prefab components aside as they arrive.

Journal Entry #41

The hearing aids arrived. I’ve got a surplus of microphones left over from the smartphone teardown, but I’d rather not use them. Smartphone microphones don’t provide particularly high audio quality, which is the reason most people doing professional recording opt for external microphones.

Hearing aids, on the other hand, are created specifically to augment the hearing of people with disabilities. They have to be good. I was careful to choose a model with a high dynamic range and wide frequency range. Many hearing aids are tuned to assist with voice perception specifically, but I want Mariimo to be able to hear anything that I can.

Obviously the included speakers won’t be necessary in this instance, as the microphones will be wired directly into her head.

I feel like I’m forgetting to mention something. I’ll add it later if it comes back to me.

Journal Entry #42

Oh right, I remember now. She’s going to have an asymmetrical microphone arrangement, to allow for more precise directional hearing. I figured I might as well complete the owl-like senses motif I introduced with the fixed cameras.

Journal Entry #43

The hard drives have arrived. I don’t have anything particularly interesting to say about them. I just thought I’d mention it.

Journal Entry #44

An important delivery today. An impressive assortment of pneumatic muscles. Every length and thickness you can imagine. A matching solenoid valve for each one as well. It took me nearly forty-five minutes to unpack the box. I’ll admit I was probably being a bit overly precious with them, but still.

At one point I started wondering if I could have just built these from scratch. The answer is yes, by the way. But there’s honestly no compelling reason I would need to. Actuators like these have been around since the 1950s. The technology has already been perfected. There’s no point in reinventing the wheel.

Nevertheless, it feels good to finally hold them in my hands.

Journal Entry #45

The supercapacitors just arrived. That’s probably going to be the last of the prefabricated shipments I’ll be receiving. From this point on it’s just going to be raw materials. Plastics, metals, fabrics, etc.

The supercapacitors actually took on a far more functional role in Mariimo’s design than I had initially anticipated. Their mass and numbers allowed for a lot of fiddling with weight distribution. Most of them ended up in her extremities, counteracting what had become a rather core-heavy design.

As it stands now, Mariimo is shaping up to be quite a finely balanced machine.

Journal Entry #46

The digital prototype is nearly complete. A few more days polish and it should be good to go. The fact that I started with detailed blueprints made the whole process go a lot faster.

I had to make a few minor adjustments based on the measurements of the prefab components as they arrived. There were a few unexpected discrepancies between the advertised dimensions and the actual dimensions, but I managed to smooth everything over design-wise.

Her external appearance remains unaltered, thank goodness. I’ve actually grown rather attached to her, aesthetically speaking.

Journal Entry #47

Aaand done. I’ve created a fully detailed 3D model of every individual component in Mariimo’s body, ready to be fed into the CNC milling machine.

I think I’m going to take a week off before I begin actual physical fabrication. Clear my head. Relax. I’ve been working fourteen hour days for longer than is probably healthy. I’ve always had a tendency to push myself too hard.

I’m going to spend the next seven days on low-power mode. Make some tea, curl up with a good book, just take it easy.

I’ve earned it.

Journal Entry #48

I made it two days. Two days before I couldn’t stand not working anymore.

The book I picked out was a story about robots and artificial intelligence. Probably not the best choice to take my mind off robots and artificial intelligence. I couldn’t even sit back and enjoy the story. I was constantly sidetracked by thoughts about the feasibility of these fictional machines. How they might be achieved in reality. The actual narrative just seemed like background noise.

I almost tried wandering the grounds, but the sound of traffic makes me anxious. It also makes me think about autonomous vehicles, which makes me think about robotics in general, which makes me think about the project. Even the most tenuous reminder of anything robotics related sends my brain off on a technical tangent that lasts for hours. It’s a compulsion.

I’ve been like this ever since I was little. My mom used to call it freight train brain. Can’t slow down. Can’t change direction.

It’s been a challenge. I struggled in school. My interests were too narrow. None of the curriculum could hold my attention. I would just end up fidgeting anxiously at my desk for hours. Eventually it began to affect my mental health, and my parents pulled me out of the system.

I was home schooled from then on, but even then it involved a lot of answer sheets and fudged test scores. My parents seemed to turn a blind eye toward the whole thing. I tried to hide it, but they had to have known. I don’t think I would have gotten away with it otherwise. When I finally turned sixteen, I was legally allowed to just drop the whole charade and give up.

I never actually graduated high school.

Journal Entry #49

Okay, the CNC milling machine has been prepped and is currently doing its thing. CNC milling takes time, but it’s a lot better than doing it by hand.

I’ve started with the PVC components, as they’ll make up the bulk of Mariimo’s armature. In the end, I decided against going full PVC. It’s tough stuff, but I was concerned about friction wear and stress damage in her joints. I decided to reinforce them with aluminum bearings. The weight and elasticity of plastic. The resilience of metal. It feels like a good compromise.

I’m going to start looking for odd jobs to pass the time while the milling machine whittles away.

Journal Entry #50

I hauled a huge spool of copper wire up from the basement today. I figured I‘d start work on the copper coils needed for inductive charging. Nice mindless work. Relaxing.

The coils in the soles of her feet are going to be about six and a half centimeters in diameter. The pair inside the charging stand will be larger, at roughly fifteen centimeters each. The size difference will allow for some leeway regarding foot placement. Hopefully this makes it a bit easier for her to charge herself autonomously.

The stand itself is going to be machined out of a nice charcoal gray PVC, just a shade darker than her neoprene skin. It was a little tricky to find raw PVC in that particular color, but I think that the end result will be well worth the effort, aesthetically speaking.

Journal Entry #51

Took it easy today. I’d finished work on the copper coils, so I figured I’d take a couple hours to prepare the soles of her feet.

I used a laser cutter to cut a pair of circular disks from a sheet of self-adhesive polyurethane rubber, the same material used in the soles of shoes. Mariimo actually has a relatively small footprint, but the extra friction provided by the rubber soles should help compensate for the minimal surface area.

I also used the copper coils and a rubber sheet to assemble a quick and dirty inductive charging test. I wanted to check and see if the polyurethane layer would interfere with the charging process. According to the readout on my multimeter, it doesn’t seem to have any significant impact.

Journal Entry #52

When it came time to disassemble the digital prototype into individual components for fabrication, Mariimo’s neoprene skin was a bit of a stumbling block. I had to teach myself how to create a sewing pattern by cutting a 3D model into segments and flattening them out into two-dimensional shapes, which is something I had never attempted before. There was a bit of a learning curve.

Today I was prepping the laser cutter to cut the neoprene into the pattern I had prototyped on the computer, but fortunately I thought to stop and do a quick safety check first. As it turns out, cutting neoprene with a laser releases plumes of chlorine gas, which can corrode the glass optics in the laser cutter itself. It probably wouldn’t do my lungs any favors either.

Looks like I’m doing this one by hand.

Journal Entry #53

I’ve assembled the various fabrics and foils needed to start work on Mariimo’s touch sensors. These I can cut with a laser.

It’s a good thing too, because there will be a lot of them. The laser cutter will save me many, many hours of fumbling with scissors. I’ll need to get more involved when it comes time to sew the layers together, but my new sewing machine will help scoot the process along.

The flatlock sewing machine is the latest addition to the prototype lab. As you might imagine, there wasn’t much demand for textiles back when my parents were in charge of the lab. I purchased the sewing machine especially for this project.

It’s a pretty heavy-duty machine, which is important because it has to chew through four millimeters of neoprene rubber. Not exactly light work.

Journal Entry #54

It was a little tricky to do by hand, but I finally managed to cut out the neoprene panels that will make up Mariimo’s skin. There are a few more steps remaining before they’re ready to sew together, however.

I still need to screen print the circuits needed for the touch sensors onto the neoprene using a conductive metallic paint. The prototype lab has screen printing supplies on hand for creating more traditional fiberglass circuit boards. With a few minor adjustments, they should work just as well for creating flexible neoprene circuit boards.

After that, I can arrange the touch sensors into their predesignated pattern, laminate both sides with an appropriately colored nylon knit fabric, trim off the excess, and punch holes along the edges for the eyelets and paracord.

It probably would have been easier to do all of this before I cut out the neoprene panels, but I’m clumsy enough with scissors that I didn’t want to risk ruining all that work with a stray cut.

Journal Entry #55

I’ve started fiddling with Mariimo’s charge indicator. Usually a segmented electronic display is the kind of thing you’d outsource to a specialist manufacturer, but I’ve already got all the materials I need left over from my faceplate experiments. I just need to apply the electrophoretic microcapsule suspension to a flexible film instead of a polycarbonate shell.

It’s probably for the best that I do it myself. Ordering custom electrophoretic displays usually entails enormous bulk orders. I really only need the one.

Journal Entry #56

For Mariimo’s memory foam inserts, I’m going to use a technique called pressure cutting. It’s the same technique used to create lightweight, inexpensive department store mannequins.

The process begins with a set of molds. I’m using the 3-axis milling machine to carve them out of medium-density fiberboard while the 5-axis machine is busy with the PVC components.

When the molds are complete, a thick slab of memory foam will be layered on top, and the entire assembly will be passed between a set of rollers, compressing the memory foam while a thin, sharp blade slices away the excess material.

When the final product pops out the other side, the two layers of foam are separated, resulting in both a positive and negative impression of the original mold. It’s honestly a little difficult to describe. The process is kind of counterintuitive.

I’m going to use zip ties to secure the memory foam to Mariimo’s armature. They’re easy to replace, so I can simply snip them away in the event that I need to access her internal machinery.

Journal Entry #57

Mariimo’s PVC components are finally complete. That leaves the 5-axis CNC milling machine free. I’m going to give it a thorough vacuuming and get it prepped to start work on her air compressor.

The air compressor is going to be machined from several blocks of solid aluminum. I’ll need to switch out the current rotary bits for a more suitable set, but other than that the milling machine is fully capable of handling metals.

The only part of the air compressor that won’t be made from scratch is the motor. That motor is going to be the heart of the machine, so it’s vital that it be of the absolute highest quality.

Lucky for me, I found the ideal candidate while I was reviewing inventory early on in the project. It had been kicking around in storage since my parents were still around. It may not be the latest model, but I learned a long time ago that newer doesn’t necessarily mean better.

Journal Entry #58

Mariimo’s polycarbonate faceplate is going to be the focal point of her entire design. It’s going to require special attention.

I can use the CNC milling machine to get started, for sure. However, that’s only the first step of many. In order to get that beautiful frosted matte finish I’m after, it’s going to take hours of careful scouring, polishing, buffing, and sandblasting. It’s got to be flawless. I have a very specific vision.

When I’ve managed to get the outer surface of the faceplate looking just so, I can go ahead and apply an electrophoretic display to its inner surface, using the same techniques I developed for my cereal bowl prototype.

If all goes according to plan, this faceplate is going to be the single most beautiful component I’ve ever created.

Journal Entry #59

I’ve already managed to gather all of the electronic components needed to create Mariimo’s motherboard. Today, I started work on the printed circuit board that will house them all.

Like I mentioned before, the prototype lab contains all the equipment and materials needed to create PCBs. It’s a fairly straightforward process. I’ve done it plenty of times before. But this time it feels different, somehow.

I hold this simple piece of copper coated fiberglass in my gloved hand, fresh out of a corrosive chemical bath, and I can’t help but think to myself: This is it. This is the scaffolding of a mind.

I can’t even begin to describe that feeling.

Journal Entry #60

Okay, the printed circuit board is complete. It looks gorgeous. It has the same shield-like silhouette that her faceplate will have. You can already see where the cameras will be wired in. It almost feels alive, in a way. Like it’s got a little personality of its own. It’s quite endearing.

I’m getting way ahead of myself though. It’s got a long way to go before it becomes a functioning motherboard. Luckily, micro soldering is one of the few fine motor skills I’ve become really proficient in since the accident.

Journal Entry #61

I fell asleep in my chair last night. I was just sitting in my office, staring at my marimo colony. The water in that aquarium is so still, and so clear. It always helps temper my anxiety.

By the time I woke up, the milling machine had already finished carving Mariimo’s polycarbonate faceplate. The benefits of automation, I suppose. I’ve spent the morning gently scouring out the ridges left behind by the milling process. It’s relaxing work. Simple. Repetitive. Gives me time to think.

Journal Entry #62

Oof. Perhaps too much time to think.

Journal Entry #63

Okay, Mariimo’s faceplate has been scoured, polished, and buffed. Perfect optical clarity. It’s like looking through distilled water. Of course, now that I’ve gone to all that work, it’s time to muck it up with a good sandblasting.

I’ve been practicing my sandblasting with spare scraps of polycarbonate sheet. I need to frost the surface enough to diffuse the light passing through it, but not so much that her facial expressions become obscured. It’s a delicate balance.

I also need to make sure that the surface has a completely even finish. No flaws. No imperfections. That’s honestly been the trickiest bit.

I’m getting the hang of it though.

Journal Entry #64

The sandblasting went surprisingly smoothly. After giving the faceplate a good rinse, I went ahead and applied the electrophoretic display. Once again, I’ll refrain from going into too much detail about the process. My patent application is still pending.

As it stands now, the faceplate is a smooth, even gray color. The pigments inside the microcapsules are still jumbled. I’m going to write a simple program this evening to test the display. I’ll have it done in time to run the test in the morning.

Journal Entry #65

I ran the faceplate display test last night. I couldn’t help myself. I had finished writing the program, and I knew I wouldn’t be able to sleep without at least giving it a shot, so I wired up the display.

It worked flawlessly.

The display flashed from a smooth, even gray to a brilliant paper white. It cycled rapidly between black and white a few times for calibration purposes, before settling back on white.

Then her face appeared. For the first time. Two clean, simple rings in a gentle achromatic gray. They just stared for a moment, ran a simple blinking animation, and began cycling through various facial expressions.

It was just a simple slide show. There was no thought or purpose behind it. Yet I couldn’t help but feel as if she were staring directly at me. Addressing me, personally.

What a notion to fall asleep to...

Journal Entry #66

I spent the day doing a comprehensive inventory check. Each of Mariimo’s components are complete and accounted for. Every single one. I’m ready to begin assembly.

It feels fantastic.


About the author

Tyrel Pinnegar

Bio: Author of MARiiMO and Rabbit Hole.

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