Sawppy at SCaLE 17x: The Trouble with Rovers

My primary obligation for Southern California Linux Expo (SCaLE 17x) was to co-present The Trouble with Rovers with Lan Dang on Saturday afternoon. Which meant when Sawppy’s coupler broke Friday evening I had to scramble to fix it for Saturday. A rush repair job is always going to leave some details to be desired but it was sufficient to resume operation.

Sawppy will obviously be one of the visual aids present at our talk, but that doesn’t mean it gets to spend the rest of the day just sitting around. No sir, as soon as Sawppy arrived on location, it immediately started working as a roving billboard for both itself and the talk.

Sawppy Scale 17x Sat 1 - Roving billboard

It was not explicitly coordinated beforehand, but the SGVHAK rover was also equipped with advertising for our talk. Both of our rovers were out and about, pulling roving billboard duty, and occasionally our paths crossed in the hallways of SCaLE.

Sawppy Scale 17x Sat 2 - Two roving billboards

I was happy with the turnout for our rover session. While we did lose a few people who left partway through the talk, it was more than made up for by the enthusiastic people who followed along and came up to ask questions after. I had a lot of fun explaining details on what we did for both rovers, minutiae that we trimmed from the talk proper but was still interesting to our smaller and more technical audience afterwards.

Sawppy Scale 17x Sat 3 - Session

Sawppy continued to roam around Pasadena Convention Center, spreading word of my rover project to people who are excited about the possibility of building their own. Some people thought it would be their motivation to finally buy their own 3D printer, others have all the tools on hand and it’s just a matter of prioritization and finding project time. I was most gratified by a group of students from California State University San Bernardino who thinks it would be a great group project. They are exactly the target audience!

And it’s fun as always to see young children’s faces light up when they see Sawppy, some of whom were eager to take control. My favorite was this 6-year old who loved to drive Sawppy over his own toes over and over.

Sawppy Scale 17x Sat 4 - Self foot runover

(Cross-posted to Hackaday.io)

Sawppy and SGVHAK Rover will be at SCaLE 17x

This year’s Southern California Linux Expo (SCaLE 17x) begins today. Four days of talks across multiple tracks focusing on topics relating to the flagship open source operating system in various ways. From small micro controllers to large cloud infrastructure. Last year’s SCaLE served as deadline and motivation for completing SGVHAK Rover, but it was only for purposes of show and tell. We couldn’t yet do a full presentation as the JPL Open Source Rover project has yet to officially launch until mid year.

But that is no longer a concern, and we even have spinoff projects like my Sawppy rover to add to the mix. Hence Sawppy will be part of our SGVHAK presentation “The Trouble with Rovers“: they’re never really finished, and their numbers keep growing. Rovers are such cool projects to work on there’s always more upgrades and evolution we can perform to make our rovers better. Lan and I practiced this talk at last month’s SGVLUG meetup and hopefully our presentation will be better for it! We’ll be presenting Saturday afternoon 4:30-5:30pm in Ballroom G.

20190214 Rovers at SGVLUG

Sawppy will also be present at the Tindie+Hackaday Bring-a-Hack meetup, under their “Birds of a Feather” event umbrella for groups to get a space and meet. It is a free event (with at least a SCaLE Expo Pass) and Sawppy will be there as representative of one of the projects with a page on Hackaday.io. This will take place Friday evening 7pm-8pm in Ballroom B.

Beyond those events, Sawppy will be generally hanging out and cruising about the event and the expo floor. There’ll probably be some time spent at the SGVLUG/SGVHAK booth, but no official scheduled events beyond the two above.

(Cross-posted to Hackaday.io)

W6TRW Amateur Radio Club Swap Meet

This week I revisited 23b shop on a day when they weren’t hosting Sparklecon, during one of their regular Thursday evening meets. I brought my Neato robot vacuum work in progress as my project and it was a good discussion icebreaker with a few of the people present. One of the interesting things I learned was the W6TRW Amateur Radio Club Swap Meet – officially a place for people to meet and trade amateur radio equipment, it has evolved into a place to find generally interesting electronics stuff to hack on. Some people were going to go shopping, and extended an invitation to join them.

W6TRW amateur radio club swap meet

I was not a huge fan of waking up early weekend morning to brave the cold outdoors, but the guys sold me on how cool the place enough to get me out of bed at 6 in the morning. I only had twenty-four dollars of cash in my wallet, and I thought that would make sure I don’t get myself into too much trouble.

Portable Karaoke duet machineFirst of all, the promise of seeing strange things I never even knew existed was fulfilled in spades, products aimed at novel niches that I had been completely clueless about. One example: this is a portable Karaoke machine that can run off batteries and use cassette tape for music, but this is a duet machine with two microphones for you and your singing partner to maintain eye contact while you sing everlasting love to each other. I don’t Karaoke and I was fascinated there was enough demand for this product to exist.

Bowling video game with ball controllerI also stumbled across this product: a bowling video game with a custom controller shaped like a bowling ball. If I understand XaviX’s Wikipedia entry correctly, this was much like Nintendo’s Wii Bowling but came out before the Nintendo Wii did. Sadly first-mover advantage in the motion controller home gaming market did not translate into market success for this company. Or even name recognition – I consider myself decently informed in video gaming trends and I had no idea these guys existed.

Old test equipment in cardboard boxes.jpg

Closer to the original spirit of the event, old electronics equipment abound, showing signs of a full service life that started as expensive specialized equipment and now sitting in cardboard boxes looking for a new home. Since I had just $24, I was not remotely tempted to take any of these big heavy metal boxes home.

I spent my money on more modest items that had immediate use for current projects. To help me see fine details for soldering and (dis)assembly, I bought a magnifier. To help me make finer details in my circuit sculpting, I bought a smaller pair of round-nosed pliers. And finally, in an effort to build my own substitute charging dock for my thrift store Neato robot vacuum, I picked up two 120V AC to 24V DC adapters. That accounted for all $24 dollars of cash I walked in with!

SGVHAK Rover, Sawppy, and Phoebe at SGVLUG February 2019 Meeting

At the February 2019 meet for San Gabriel Valley Linux User’s Group (SGVLUG), Lan and I presented the story of rover building in our hardware hackers spinoff group a.k.a. SGVHAK. This is a practice run for our presentation at Southern California Linux Expo (SCaLE) in March. Naturally, the rovers themselves had to be present as visual aids.

20190214 Rovers at SGVLUG

We started the story in January 2018, when Lan gathered the SGVHAK group to serve as beta testers for Jet Propulsion Laboratory’s Open Source Rover project. Then we went through our construction process, which was greatly motivated by our desire to have SGVHAK rover up and running at least year’s SCaLE. Having a rover at SCaLE was not the end, it was only the beginning. I started building my own rover Sawppy, and SGVHAK rover continued to pick up hardware upgrades along the way.

On the software side, we have ambition to increase sophistication by adapting the open source Robot Operation System (ROS) which led to a small digression to Phoebe, my tool for learning ROS. Getting a rover to work effectively under ROS poses some significant challenges that we have yet to address, but if it was easy it wouldn’t be fun!

Since this was a practice talk, the Q&A session at the end was also a forum for feedback on how we could improve the talk for SCaLE. We had some good suggestions on how we might have a better smoother narrative through the story, and we’ll see what we can figure out by March.

Sawppy at Brawerman East STEAM Makers Fair

Sawppy’s publicity appearance today was at Brawerman East STEAM Makers Fair, a supercharged science fair at a private elementary school. Sawppy earned this invitation by the way of January presentation at Robotics Society of Southern California. The intent is to show students that building things is more than their assignments at their on campus Innovation Lab, there are bigger projects they can strive for beyond the classroom. But the format is, indeed, just like a school science fair, where Sawppy got a display table and a poster board.

Brawerman STEAM Makers Fair - Sawppy on table

But Sawppy is not very interesting sitting on a table, it didn’t take long before the rover started roving amongst other exhibits. The school’s 3D printer is visible on the left – a Zortrax M200.

Brawerman STEAM Makers Fair - Sawppy roaming

Sawppy was not the only project from grown-ups present. I admire the ambition of this laser cutter project undertaken by one of the parents. Look at the size of that thing. It is currently a work in progress, and its incomplete wiring were completely removed for this event so little fingers are not tempted to unplug things and possibly plugging them in a wrong place.

Brawerman STEAM Makers Fair - laser cutter

The center of this tables had some old retired electronics equipment that kids will be able to take apart. This was a huge hit at the event, but by the end of the night this side of the room was a huge mess of tiny plastic pieces scattered all over.

Brawerman STEAM Makers Fair - deconstruction zone

I brought my iPad with the idea I could have Sawppy’s Onshape CAD data visible for browsing, but it turned out the iOS Onshape app required a live internet connection and refused to work from cache. As an alternate activity, I rigged it up to show live video footage from Sawppy’s onboard camera. This was surprisingly popular with the elementary school age crowd, who got a kick out of making faces at the camera and seeing their faces on the iPad. I need to remember to do this for future Sawppy outings.

Brawerman STEAM Makers Fair - Sawppy camera ipad

After Sawppy was already committed to the event, I learned that a Star Wars themed art car was also going to be present. So I mentioned my #rxbb8 project which earned me a prime parking spot on the first floor next to the far more extensively modified “Z-Wing.” Prepare to jump to hyperspace!

rxbb8zwingcropped

(Cross-posted to Hackaday.io)

Sawppy at Space Carnival Long Beach

Sawppy at Space Carnival Long Beach

Space Carnival, held at the Expo Arts Center in Long Beach, California, welcomed Sawppy as one of several exhibits Monday afternoon. It turned out to be part of a week-long LEGO robotics camp for elementary school students. Most of the events are for campers, but the Monday evening Space Carnival was open to the public.

Since the focus is on LEGO, there were plenty of plastic bricks in attendance. The middle of the room had a big pile of bricks on a plastic tarp and kids were crawling all over the pile building their creations. Sawppy mostly spent time outside of the tarp, occasionally venturing on to some of the colorful game boards for LEGO robots to line-follow and other tasks.

Sawppy at Space Carnival Long Beach LEGO tarp

As usual, I handed controls over for kids in attendance to play with. Running over feet is still more popular of an event than I can hope to understand but, if it makes them excited, so be it.

Sawppy at Space Carnival Long Beach running over feet

Sawppy was not the only non-LEGO robot in attendance, there were also a selection of Star Wars licensed merchandise including this R2D2. I forgot if this particular unit was made by Sphero or Hasbro.

Sawppy at Space Carnival Long Beach R2D2

This event was not the first time I crossed paths with Barnabas Robotics, but it was the first time I got to speak with them beyond the standard sales pitch type of discussions. Since their business is STEM education for students K-12, they have a good feel of what type of material is appropriate for various age groups. It’s possible Sawppy can find a role in high school curriculum.

At the end of the night, the LEGO tarp cleared out enough for me to drive Sawppy across the field. Unfortunately I saw Emily’s tweet too late to replicate the movie clip she had suggested. Maybe another day!

(Cross-posted to Hackaday.io)

My Monoprice 3D Printers at February 2019 RSSC Meeting

When I presented the story of my Sawppy rover project last month at the January 2019 meet of Robotics Society of Southern California (RSSC) I made an offhand comment about my 3D printers. Later on, in a discussion on potential speakers, there were people who wanted to know more about 3D printers and I offered to summarize my 3D printer experience in a follow-on talk. Originally scheduled for March, I asked to be rescheduled when I realized the March RSSC meet would take place at the same time as Southern California Linux Expo (SCaLE).

My talk (presentation slide deck) starts with a disclaimer that my experience and knowledge was limited. I started by explaining why I chose Monoprice printers backed by a short history lesson on Monoprice because that sets the proper expectations. Then I ran through my three Monoprice printers: the Select Mini, the Maker Select V2, and the Maker Ultimate. Each of these printers had their strengths and weaknesses.

Monoprice Select Mini

  • Simple low-cost printer that still covers all the basic concepts of FDM printers.
  • Closest we have to a “Fisher Price My First 3D Printer”
  • Recommended for beginners to find out if they’ll like 3D printing.

Monoprice Maker Select

  • Classic Prusa i3 design.
  • Easiest to take apart for modifications and/or repairs.
  • Recommended for people who like to tinker with their equipment.

Monoprice Maker Ultimate

  • Design “inspired by” Ultimaker.
  • Highest precision and most reliable operation.
  • Recommended for people who just want their equipment to work.
  • But price level approaches that of many other good printers, like a genuine Prusa i3.

I brought my printers to the meet so interested people can look them over up close. I did not perform any print demos, because I’ve almost certainly knocked the beds out of level during transit. Plus, I forgot my spools of filament at home. But these are robotics people, they can gain a lot just by looking over the mechanical bits.

20190209 RSSC 3D Printers

SparkleCon Sidetrack: Does It Have A Name?

spool holder with two stage straightener 1600x1200

My simple afternoon hack of a copper wire straightener got more attention – both online and off – than I had expected. One of these came as a fun sidetrack to my Sparklecon talk about my KISS Tindie wire sculptures. As part of the background on my wire form project, I mentioned creating this holder. It kicked off a few questions, which I had answered, but I had the most fun with “Does it have a name?”

I gave the actual answer first, which was that I had only been calling it a very straightforward “wire spool holder with straightener” but I followed it up with an off-the-cuff joke “Or did you mean a name like Felicia?” I think I saw a smile by the person asking the question (hard to tell, he had a beard) and I also got a few laughs out of the audience which is great. I had intended to leave it at that, but as I was returning to my presentation another joke occurred to me: “Felicia will set you straight.”

Since my script was already derailed, I saw no reason to run with it: “Is there a fictional character who is a disciplinarian? That might be fitting.” and opened it up to the audience for suggestions. We got “Mary Poppins” which isn’t bad, but things went downhill from there. The fact is: the disciplinarian in a story is almost always a killjoy obstacle in our hero’s journey. Or worse, one of the villains, as in the suggestion of “Delores Umbridge” given by a woman wearing a Harry Potter shirt. My reaction was immediate: “No.” But two seconds later I remembered to make it a tad more positive: “Thank you, she is indeed a disciplinarian, but no.” Hopefully she doesn’t feel like I bit her head off.

After the talk, there were additional suggestions interpreting my second joke “Felicia will set you straight” in the sense of personal relationship preferences. This went down a path of politically conservative zealots who believe it is their public duty to dictate what people do in private. This direction of thinking never even occurred to me when I threw out the joke on a whim.

I think I’ll leave it at Mary Poppins.

SparkleCon Day 2

A great part of SparkCon is its atmosphere. It is basically a block party held by 23b Shop and friends in the same business park. Located in Fullerton, CA, the venue’s neighborhood is a mix of residential, retail, and commercial properties. As a practical matter, this meant good eats like Don Carlos Mexican Restaurant and Monkey Business Cafe were in easy walking distance.

Originally my Day 2 was going to start bright and (too) early for me at 9AM with the KISS Tindies presentation, but the relaxed easygoing nature of the event meant a schedule change was possible and we did it at noon instead. I loved talking to all my fellow people who thought my circuit sculptures were more interesting than a certain football game taking place around the same time.

Roger presenting at Sparklecon - Drew Fustini
Photo by Drew Fustini
Roger presenting at Sparklecon
Photo by Jaren Havell

It was another great opportunity to practice public speaking. I think it went well and some people let me know afterwards that they enjoyed the talk. Success!

The table and couches of NUCC once again hosted various hacks. Emily’s little green-tinted CRT attracted immediate attention.

Emily green tinted LED on NUCC table at Sparklecon

It wasn’t long before it hosted a Matrix waterfall of characters.

Emily wants to host a version of Adafruit Hallowing’s default eyeball program on her tiny round CRT. To see how it would look, Emily and Jaren took a video of the Hallowing eyeball and played it back on a Raspberry Pi.

While this was underway, I was unwinding by playing with my copper wires. Yesterday I made a crude taco truck, today I tried to make an abstract steam locomotive out of a single wire. There was no planning involved, so it was no surprise I ran out of wire before I could finish.

Single wire steam engine

Elsewhere on the table were electronic noisemakers to play with. To the left is a “Dronie” assembled by @hackabax this weekend, next to another of his noisemaker devices whose name I forgot. Inside the metal case in the right is one of Emily’s earlier projects, a simple sequencer powered by a pair of 555 timers.

Noisemakers Unite.jpg

One casualty of the pouring rain were the robot competitions, but the Hebocon boxes were still set out for people to play with. Maybe we won’t have robots this time, but we can still have other interesting contraptions.

Hebocon boxes at Sparklecon

Sometimes “interesting” veered into “unsettling”…

Barbie head baseball flag thing

It was a great weekend, rain or no rain. I had the opportunity to present one of my projects and saw it was well-received. I got to see people I’ve met before at other events, and met some new people too. And it was a great way to learn about spaces I’ve only heard about before. Chances are good I’ll be back at 23b Shop and/or NUCC before next Sparklecon rolls around.

SparkleCon Day 1

I have arrived at SparkleCon! I had thought this event was just at the hackerspace 23b Shop, but it is actually spread across several venues in the same business park. The original plan also included activity in the parking lot between these venues, but a powerful storm ruined those plans. Given this was in Southern California the locals are not very well equipped to handle any amount rain, never mind the amount that came pouring from the sky today. So people packed into the indoor venues where it was warm and dry. STAGESTheatre is where some talks were held, like Helen Leigh‘s talk From Music Tech Make to Manufacture demonstrating her Mini Mu.

Sparklecon Day 1 mini mu

The doors of Plasmatorium was also open and primary source of music. And finally the National Upcycling Computer Collective which had this festive sign displayed.

Sparklecon Day 1 sign

One corner of NUCC was set up with a pair of couches and a table, which grew into KISS Tindie headquarters. The original plan was to set up an inflatable couch and table someplace in the outdoor region, but the rain cancelled those plans and we took over this space instead.

Sparklecon Day 1 NUCC CouchThe table started the day empty, and there was a time when it was populated by scattered stickers, but towards the evening it became an electronics workshop. Here we can see multiple simultaneous projects underway.

Sparklecon Day 1 Workbench

I had a few taco, fries, and octopus kits to give out. While talking about tacos and KISS Tindie sculptures, it was suggested that I use my newfound circuit sculpture skills to build a taco truck. So I did!

Sparklecon Day 1 taco truck

KISS Tindies will be at SparkleCon

SparckleCon IV, the annual event held by 23b Shop, will be this upcoming weekend. It will be my first opportunity to attend and it looks like I’ll be jumping in with both feet and presenting part of a talk. Currently scheduled for Sunday morning at 9AM, the topic is Hackaday and Tindie, with focus on the recently concluded circuit sculpture project.

Ironically, there won’t be any actual contest entries at the presentation, because staff members like myself were not eligible to enter. So I’m bringing the next best thing: my KISS Tindies band which I built because I thought circuit sculptures looked like fun.

kiss tindie band on stage

The talk will be a condensed summary of my circuit sculpturing adventures documented on this blog. From my initial Tindie puppy, to my wire straightening tool, to the four members of the band and finally the drum set. The topic will neatly tie into both Hackaday and Tindie and it’s my way of making sure I hit the standard points without being too much of a corporate commercial.

We’ll see how successful the venture will be… my brain isn’t typically working at its best Sunday mornings at 9AM, and some fraction of the conference attendees will be hungover in bed. I choose to see this as a positive thing: it’s good practice for my public speaking skills, and any goofs would likely go unnoticed (or at least forgiven) by an equally night-owl-heavy crowd.

Sawppy Presented at January 2019 RSSC Meeting

Today I introduced my rover project Sawppy to members of Robotics Society of Southern California. Before the presentations started, Sawppy sat on a table so interested people can come by for a closer look. My visual aid PowerPoint slide deck is available here.

sawppy at rssc

My presentation is an extended version of what I gave at Downtown LA Mini Maker Faire. Some of the addition came at the beginning: this time I’m not following a JPL Open Source Rover presentation, so I had to give people the background story on ROV-E, JPL OSR, and SGVHAK rover to properly explain Sawppy’s inspiration. Some of the addition came at the end: there were some technical details that I was able to discuss with a technical audience. (I’ll expand on them in future blog posts.)

I was very happy at the positive reception I received for Sawppy. The first talk of the morning covered autonomous robots, so I was afraid the audience would look down at Sawppy’s lack of autonomy. Thankfully that did not turn out to be a big deal. Many were impressed by the mechanical design and construction. Quite a few were also appreciative when I stressed my emphasis on keeping Sawppy affordable and accessible. In the Q&A session we covered a few issues that had easy solutions… if one had a metalworking machine shop. I insisted that Sawppy could be built without a machine shop, and that’s why I made some of the design decisions I did.

A few people were not aware of Onshape and my presentation stirred their interest to look into it. There was also a surprising level of interest in my mention of Monoprice Maker Select v2 as an affordable entry level 3D printer, enough hands were raised that I signed up to give a future talk about my experience.

(Cross-posted to Hackaday.io)

Sawppy Post-Faire Cleanup

When I work on Sawppy, I test and run indoors. At DTLA Maker Faire Sawppy ran all over, both indoors and out. Most of the time people were playing with Sawppy on a piece of artificial turf at Maguire Gardens. This is an outdoor space where people would walk their dogs, raising obvious sanitation concerns running Sawppy on my home carpet after the event.

Well, after a long day of work, who doesn’t enjoy kicking off their shoes and soaking their feet? I could give Sawppy the same royal treatment. All six wheels were removed and soaked in a tub filled with a mixture of water and household bleach. A retired toothbrush was used to scrub off dirt particles clinging to the wheel. Hopefully this removed most of the contaminants Sawppy might have picked up during the event.

Sawppy kicks off shoes

It was also a good time to perform an inspection to see how Sawppy held up mechanically. In addition to the set screw mentioned yesterday, a few chassis mounting screws have fallen out and need to be replaced. I designed plenty of redundancy in these mounts so there was little risk of Sawppy falling apart.

Sawppy lost fasteners

After a few hours of soaking, the wheels were hung up to dry like old socks. What has six rover wheels but is not a rover? This laundry rack.

Sawppy laundry

(Cross-posted to Hackaday.io)

Sawppy at DTLA Mini Maker Faire

Yesterday Sawppy went on an adventure to the downtown Los Angeles Mini Maker Faire. There Sawppy found a receptive and appreciative audience. There were a lot of enchanted kids, interested parents, and other makers who might be building their own Sawppy rovers.

The morning started out with Sawppy sitting on a table alongside a few different builds of JPL open source rover. Eric’s build is on the left in black and white, Santa Susana High School build is on the right with purple printed parts.

Taking Sawppy around and talking to individuals about Sawppy was a lot of fun and something I’ve done in other contexts before. I have hopes for a few of the contacts to develop into something cool for Sawppy’s future. What’s new this time was that I also signed up to give a short 15-minute presentation about Sawppy and that took more work and preparation. Thanks to the 2-minute “lightning talk” opportunities at Hackaday LA the past few months I’m less nervous about public speaking than I used to be, but I still got pretty stressed about it. I’m sure it’s a matter of practice and the more I can take advantage of such opportunities the better I’ll get.

Roger Sawppy

Outside of the presentation, Sawppy and I spent most of our time on the astroturf across the walkway from the officially assigned display area. It was a hilly part of the park which meant there were no tables or booths set up there, and it was a good place to demonstrate rover suspension in action. I had a spare phone set up to be Sawppy control and handed the control to anyone who wanted to pilot Sawppy for a bit.

Sawppy on lawn.jpg

Most were content to run around the turf. Some of the little ones tried to run Sawppy into their siblings. A few ran into the bushes beyond the turf for a more rugged demonstration of Sawppy chassis. A perpetual favorite is to have Sawppy climb over shoes.

Sawppy running over feet

Thanks to refinements to improve robustness over the past few months, Sawppy came out of the experience with only a slightly wobbly left rear wheel that was easily repaired by tightening the set screw on the left rear steering servo coupler. A great improvement over earlier outings!

(Cross-posted to Hackaday.io)

Sawppy Will Be At DTLA Mini Maker Faire

The Downtown Los Angeles (DTLA) Mini Maker Faire, hosted at the Los Angeles Public Library central location, is coming up this weekend and my rover Sawppy will be among the many maker projects at the event.

DTLA Mini Maker Faire Website

Sawppy will be one of several rovers present. JPL’s Open Source Rover team should be there with their original build, SGVHAK will be there with the beta build rover I contributed to, which inspired my Sawppy and they’ll all be hanging out together.

The JPL team will also be giving a brief presentation in the KLOS Children’s Theater upstairs about their rover project, followed by an even briefer presentation by me on building Sawppy. Both of these talks are listed on the workshop schedule though (as far as I know) there is no hands-on workshop activity planned. Sawppy will be present and running for people to see up close, but no assembly (and certainly no disassembly!) is planned. I may bring an extra corner steering unit for people to play with, and they’ll be welcome to take that apart and put it back together, but not much beyond that.

(Cross-posted to Hackaday.io)

Highland Park Railroad Open House

HPRR01 - WelcomeHighland Park Society of Model Railroad Engineers is my local railroad club. I appreciate the detailed work that goes into a model railroad layout but I haven’t decided to spend the time and money required to do a good job at it myself. Still, when they hold an open house, I go and admire the work they’ve put in. This is a train layout that has been worked on by club members for most of the last seven decades!

The club house appears to be literally a house – a former residential building that has now been completely taken over by the club. Roughly half of the available square footage inside are train tracks, with the remainder used for support equipment, workshops, and general club space.

HPRR02 - Layout Partial

“Does your train of thought have a caboose?” Generally speaking… mine do not.

HPRR03 - Safety and Caboose

The general theme is 1940s-1950s America, conveniently covering the final transition period from steam locomotives to modern diesel electric and all electric trains. Since this club is in the Los Angeles area, there are trains inspired by local history, like some Red Cars.

HPRR04 - Red car

A scratch built reproduction of Angel’s Flight climbs the side of a mountain rather being in the middle of a city like the real thing.

HPRR07 - Angel's Flight

A steam locomotive was set up as if it’s on museum display.

HPRR08 - Highland Pacific locomotive display

And behind the museum piece, an impressive train station.

HPRR09 - Union Station

One of several train yards in the layout, anchored by a big turntable.

HPRR11 - Turntable

Another train yard featured a group of train enthusiasts taking pictures. I wonder if the figurines are modeled after specific members of the club who would go on such trips.

HPRR15 - Train phtographers

Many little towns dot the layout.

HPRR16 - Town

Some of the town buildings have storefronts inside.

HPRR17 - Town detail

This bridge painting crew is having a bad day.

HPRR12 - Bridge painters

Locomotives running on the layout are under command of train engineers at these stations, coordinated by a dispatcher.

HPRR10 - Train engineers

Behind the scenes, a massive panel of relays manage the layout.

HPRR05 - Relay panel

Wire-wrapping was already a technology on its way out when I started learning electronics, but given the age of the club, it’s not surprising that some wire wrapping is still present.

HPRR06 - Wire wrapping

The power conversion and distribution panel.

HPRR14 - Power supply

Venturing underneath the train tracks is not for the faint of heart or the easily confused, but it’s far more spacious and less cluttered than I had expected.

HPRR13 - Underneath

One of the many objectives of the open house is to recruit new members to the club. While I’m very appreciate the work, I think I’ll stick with software and robots rather than get into model trains.

Still, I’ll probably stop by on the next open house.

Eyes At Supercon: Adafruit HalloWing

HalloWing CloseupAnother key attraction in the Supercon swag bag was a HalloWing from Adafruit. Not just the module, a complete package: in order to make sure Supercon attendees can immediately start playing with it, a battery is included. Plus a lanyard to make sure we can wear it for others to see and start conversations about this Adafruit product. It’s exactly the kind of thing we’d expect as a sponsorship item in the swag bag. Adafruit has produced a lot of products that appeal to this exact audience, along with a ton of tutorials and useful reference information that have helped me in my own explorations.

The Supercon edition of HalloWing came with a custom firmware running through a simple slide show. It cycles through a few bitmap images of event sponsor logos: Adafruit logo, Hackaday logo, Digi-Key, etc. But that barely scratches the capability of this module.

Reading Adafruit’s product information page, it looks like one signature attraction of the HalloWing is that it’s one of the boards with support for CircuitPython. A recent addition to Adafruit’s grand plan to make electronics more approachable to more people, it is hoped that Python would be even easier for beginners to pick up than Arduino.

As my first experiment, I tried to modify the slide show. I translated each animation frame of Nyan Cat into 128×128 bitmap files and loaded them onto my HalloWing. By editing slide show parameters like removing transition effects and shortening time between slides, I had hoped that I can turn the slide show into a crude animation of Nyan Cat in action. Sadly I took a wrong turn somewhere, and my HalloWing no longer boots up. I suspect I skipped a critical step for updating slide show program’s CircuitPython source code and managed to corrupt storage.

Fortunately it was easy to reset the HalloWing with a fresh copy of its firmware. Standard (non-Supercon) HalloWing purchased from Adafruit comes with “spooky eyes” firmware that displays an eyeball that randomly looks around. I followed instructions and my HalloWing is back up and running with an eyeball. Side bonus, it looked cooler than a slide show.

This is just a start. I look forward to digging more into this board’s possibilities in the near future. CircuitPython, Arduino, and at the center of it all? A SAM D21 chip, part of the line I just learned about at Supercon.

I foresee a lot of fun with this new toy.

Gifts At Supercon: Sponsorship Swag Bag

When I checked in to Supercon Saturday morning, I was given the items given to every Supercon attendee. A T-shirt, of course. A magazine (pamphlet? flyer?) titled Supplyframe RealTalk Electronics. A small water bottle, and a reusable tote bag filled with stuff.

Supercon2018 Goodie Bag

In the background of this picture is the tote bag. All the stickers in the bag were laid out to the lower left: two Tindie stickers and many more Hackaday stickers of all types. On the top is a Hackaday postcard. All fun stuff, but what excites Supercon attendees are the electronics.

The orange item in the upper left is the enigmatic Supplyframe cube. A 3D realization of their company logo, it has electronics inside for a purpose mysterious to Supercon attendees (at least at first.)

Next to the cube, sitting on top of its antistatic bag and nearly invisible due to its size, is a Tomu. A complete ARM powered computer on a circuit board the size of a USB plug, it is remarkable here because it was still in development at last year’s Supercon. At the time its creator had solved most hardware issues and was recruiting people to help write the supporting software. I heard the recruiting pitch but sadly my programming skills were not aligned with the project’s needs. It’s great to see that others have pitched in and made Tomu a reality.

Next to Tomu is a LED circuit board in the shape of Hackaday’s Jolly Wrencher logo alongside a Tindie LED badge of similar function. Many attendees soldered these up through the weekend for a little bright wear.

Below the Tindie badge is a Sparkfun Roshamglo board. I read the product description saying it was an electronic way to play rock-paper-scissors over infrared signals, but I knew that couldn’t be the whole story because there’s obviously a USB connector at the end and you don’t need that for a silly little game. And further reading confirmed the rock-paper-scissors was only the default firmware – users can use the Arduino IDE to program the onboard ATTiny84 chip to do something else. This might be a fun exploration.

And last but not least, in the lower right peering back at the camera is an Adafruit Hallowing. It is shown assembled here because I couldn’t wait to take a picture before putting it together. More on this nifty little board shortly.

Shine At Supercon: Pixelblaze Cube

When I was working on my time-lapse camera badge hack for last year’s 2017 Superconference badge, I had the luck to meet Ben a.k.a Electromage, creator of Pixelblaze. He was sitting across the table from me and had to stare at the backside of my Luggable PC Mark II for most of the weekend. Our paths crossed again earlier in 2018 at the Bay Area Maker Faire, where I was working for Tindie‘s booth and he stopped by to drop off a sample Pixelblaze unit as he sells on Tindie. After my booth shift was over, I stopped by his booth set up to promote Pixelblaze and was impressed by what I saw.

I don’t recall anything demonstrating Pixelblaze at Supercon 2017, but Ben brought a nice attention-pulling demo for Supercon 2018: a sound-reactive LED cube controlled by Pixelblaze with optional sensor expansion board. It was sitting in front of him on the badge hacking bench as he worked most of the weekend on that ESP32 mesh network. Here’s a view of the cube looking down the length of the bench at all the other badge hackers.

Pixelblaze Cube

The cube’s five visible sides each had an 8×8 = 64 LED array, and they react to changes in sound volume. The microphone is part of the sensor expansion board and is paired with its own processor to dynamically adjust to local ambient noise level to pick out sharp changes. All that audio processing was required, Ben explained, because electronic microphones don’t react to sound the same way human hearing does. His algorithms make the sensor board act similarly to how a human being perceive sound. All this is necessary so a Pixelblaze program reacting to sound would “look right” to a human observer.

After seeing Pixelblaze in action at Bay Area Maker Faire, I added “play with Pixelblaze” to my electronic to-do list. Seeing this sound-reactive demo cube in action at Supercon 2018 promoted it higher on my list. And now, thanks to an unexpected series of events and Ben’s generosity, I now have one on hand I could play with.

My first challenge: I don’t have an individually-addressable LED strip/array to use with this Pixelblaze. Reading Pixelblaze documentation I learn the APA-102 series of LED modules are the best match for Pixelblaze capabilities, so I’ve ordered a meter long strip to start. I’m looking forward to seeing what I can do with it.

Miss At Supercon: ESP32 Mesh Network Demo

In the pre-Superconference badge hacking call to action, wireless badge communication was raised as a specific challenge laid out for attendees to tackle. One particularly ambitious effort was to build a mesh network for wireless communication using ESP32 modules mounted to the badge expansion header. The ESP32 mounting system is straightforward, it was the software that would prove to be tricky.

At the end of the weekend, Morgan and Ben got the network up and running with just over an hour to spare. They started recruiting people to join their IRC-style chat network for the final demo, and I signed up. In the test session I was able to see messages sent over the network, and send a few myself. But when it came time for the actual demo on stage, my badge was unable to connect! Fortunately they had enough other participants so my participation was not critical, but I was sad to have missed out. After the presentation (and winning a prize) the team told everyone on the network we could keep the ESP32 as a token of thanks.

After the conference I examined my ESP32 mount and found a few cracked solder joints. It looks like I had accidentally smashed my ESP32 module sometime between the test session and the presentation. Looking on the Hackaday.io project page, I found the simple schematic and tested connections using my multimeter. Several connections were indeed severed between the badge header and the mounting circuit board. I tried the easy thing first by reheating all the solder to see if they could bridge the gaps. This helped, but two lines remain faulty and were patched with wires.

After this patch, I tested with [mle_makes] ESP32-equipped badge and we could not communicate, indicating further problems with my ESP32. The next step is to desolder it from the board to see if I could use the ESP32 as a standalone module. Once the module was removed from the carrier board, I saw a problem: three of the pads had separated from the module, one of them being the EN(able) pin critical to a healthy ESP32. The other two damaged pads (IO34 and IO35) I hope I could live without.

Is this the end of the road for my gifted ESP32? I thought it was, but [mle_makes] disagrees. The next experiment is to try soldering to the trace leading to EN pad, or the via further inboard. This will be a significant challenge – that via is smaller than the tip of my soldering iron!