School of Maaa

Still catching up on the activities of this summer. One of the closing events and highlights was spending a few days in Berlin teaching at the School of Machines, Making & Make-Believe.

I spent 3 days with around a dozen students from a variety of backgrounds. They included artists, designers and engineers. The general topic I was teaching was wearables. It was the second week of the programme and everyone had some amount of experience with Arduino.

I started my sessions with a bit of background about myself and a broad overview of the intersections of e-textiles, wearables and art. We then started with switches in the afternoon.

The big technical topic of the afternoon was the role of pull up and pull down resistors.

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E-Textile Summer Camp 2014


This past July I got to participate in a week-long camp that I think will remain a top highlight of 2014. I attended the E-Textile Summer Camp 2014 at the Paillard Centre d’Art Contemporain & Résidence d’Artistes. I was accepted last year, but then was gutted when my passport and visa didn’t arrive in time from the UK government to let me travel. (I didn’t know it then, but I wouldn’t receive it for another 5 months past the camp, so it wasn’t really a close call. Thanks, Theresa May.) So I was super eager to attend this year.

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A Necklace

Necklace Exhibition

Stephanie Posavec was invited to contribute to the Futures 10 – the closing exhibition of the Wearable Futures Conference.

I was given the theme of ‘memories’. As an urban pedestrian, I often walk by memorable locations from my past, and imagine how my memories are layered upon the city over the memories of those who lived before me. I wish I could experience these memories more clearly, so I decided to create a device that would make one’s memory traces more physical and tangible. This device tags memories to a location, gathering audio and emotional data and providing a 3d-scan of the memory space. Memory maps are created over time, as personal or shared maps, and maps of past lives can be accessed by loved ones as a form a remembrance. Later, through the use of audio and haptic feedback, while walking through the city a user is able to ‘brush up’ against a 3d-texture of a memory and feel and hear important moments from their past.

Stephanie on Memories in Wearable Futures

Stephanie is an amazing visual designer and largely works with data visualisation for print, so designing an inactive wearable piece was outside her comfort zone. I think she did a great job, but she wanted some help to bring her concept off the page and make a physical prototype. We spent a day together creating the pendant for her piece.

She decided to represent the interaction through a pulsing light embedded in a necklace. She designed the light pulsing pattern and colour to show different types of memories and I got an RGB LED mocked up with an Arduino and breadboard.Prototype of Necklace

Once the colour and tempo was finalised, I programmed an ATtiny45 to do the same as the Arduino. We wanted the piece to be as small as the tech would allow, so I soldered the LED and resistors directly to the microcontroller. The pendant was constructed from two pieces of walnut wood sandwiching a piece of acrylic to diffuse the light. The circuit board was created from pieces of copper tape. The adhesive of the tape made a fairly strong contact against the wood.

Construction of Necklace

The finished pendant had a roughly 30 second cycle of 5 memories with different attributes of being personal, shared, or in remembrance.

Necklace Colours

Stephanie turned the pendant into a full necklace along with designing two boards to explain the concept. My photos and video of the exhibition aren’t great, but hopefully sufficient to get an idea of the finished piece.

It was kinda funny, and quite characteristic of those in attendance, that everyone felt very comfortable touching the pieces. The circuit on the back of the pendant was not intended for public viewing; it was supposed to hidden against the body when worn. But the necklace kept getting flipped over by curious attendees to inspect the tech.

Futures10 Necklace from Becky Stewart on Vimeo.

A Onesie

To round out 2013,  I’m going to post three projects I completed in November and December. All three were ideas that had been thought about for varying lengths of time, but were each executed in a single day. The first two, both wearable technology pieces, are more related than the third, a bingo card game.

Baby Onesie

This project was a very quick commission to provide a proof of concept for what wearable technology for children could be. It was part of an investigation for a funding bid into whether wearable tech could enhance play between parent and child.

Babyglow Onesie from Becky Stewart on Vimeo.

It was a very quick turnaround. I was approached on a Tuesday and the piece was needed the following Saturday. It was requested that the garment be a onesie or baby-grow, but that the interaction was largely up to me. The point of the piece was to demonstrate to parents in a workshop what a finished piece of wearable tech could look like as they were going to be shown other sensors and actuators outside of a finished piece.

I ordered in some kit on the Wednesday and Thursday then started and completed the piece on the Friday.

The concept was very simple: an appliqué of three balloons that appear white when the garment is not powered, light up in three different colours and then change colours when the child jumps up and down. This movement was detected by an accelerometer on the right leg.

The onesie was purchased off the high street. The appliqué was created by using several layers of white tulle as a diffuser and white cotton fabric. The tulle was an ok diffuser, certainly acceptable within the time limits and materials on hand for experimentation, but I would want to improve it if the project were to move forward. The photo looks less diffuse than it appears in person.


The underlying electronics are three Adafruit NeoPixels controlled by a LilyPad SimpleSnap with a LilyPad Accelerometer on the leg. The NeoPixels were the breadboard-friendly version as opposed to the ones explicitly designed for soft circuits as they were the easiest to get ahold of quickly. They don’t ship with the header pins soldered on, so you can use the via holes for the header pins for sewing.

Onsie LEDs

As there were some longer runs for the circuit, I decided to try conductive ribbon for the first time. The type I chose advertised a low resistance and that it didn’t short if folded on itself. Overall, it was much better than working solely with conductive thread, but the transition from the ribbon to the components is a little awkward.

The Lilypad was attached to the lower back using snaps. The placement was in hope that it would be the most difficult place for the child to reach. It was placed low on the back so that it wouldn’t poke into them if they leaned back against something.

The SimpleSnap comes with female snaps already soldered onto the pads, which seemed convenient as I would have done that myself anyway. However, it didn’t actually come with the corresponding male snaps which was a big pain. It took a while to track down the right size snaps and now I have a handful of females snaps leftover without male pairs. However, the integrated battery is a big plus.

Back of Onesie

If I had more time, I would have created an appliqué to cover the accelerometer as well.

There is nothing particularly clever or groundbreaking in the code, but it’s up on Github.

Finished Onesie

The Quickest of Hacks with Moving Brands and Bare Conductive

This past Saturday I attended a hack day hosted by Moving Brands (#MBInkHack on Twitter). The hack centered around working with Bare Conductive’s Electric Paint (which is often referred to as the misnomer conductive ink). After accepting the invitation I was incredibly excited to learn that we would also get to try out the Touch Board – Bare Conductive’s new product not due to ship until March.

The hack day started at 10am and we were in the pub by 5pm. Certainly the shortest hack day I’ve attended. It was only 4 hours of actual hacking, but the results were amazing. You couldn’t fool yourself into thinking you could accomplish anything huge and everything was physical. It was so refreshing to not have a single website developed and presented at the end of the hack.

I worked with Ben Fields and Alan Waldock. Emilie Giles joined us around midday and was trooper working through a cold brought on by London’s change of seasons. Our concept was to create an instrument out of a paint roller where you roll the paint roller over a score to play the music. Like a physical audio scrubber. We had hopes of implementing a copper tape and brush rotary system to actually allow the roller to freely rotate, but that just wasn’t feasible in our limited time. We instead painted conductive paths with Electric Paint using a stencil Al created.

The Touch Board has onboard capabilities to be a MIDI instrument and handle capacitive touch sensing all programmable from the Arduino toolchain.  We had 12 stripes of paint each hooked up to a capacitive input which triggered a MIDI piano note.  The board has an amp and direct audio out along with a connector for a LiPo and built-in charger, so the whole thing was entirely wireless.  We plugged in a little portable speaker and a LiPo and we had “music”.

There was a lot of video and photos taken with some quite expensive cameras, but that’s not released yet. So here are some photos from phones.

Rock 'n Roller


There were 7 groups of 3-4 people.  All of the resulting hacks were amazing and are easier to explain via video and photos rather than awkward text, so I’ll update this post when videos are put up online.

I’m just so impressed by the thought behind the board.  There is nothing shiny and brand new on it; it’s a bit of a Frankenstein’s monster of various open source projects.  But it’s all put together with so much consideration.  It fits beautifully within existing open source hardware projects, which Nick Ludlam (CTO of BERG) noted when he brought along BERG’s Devshield.  He popped it on the Touch Board and both played nicely with each other right away.

Thank you to Moving Brands for putting on the event and thank you to Bare Conductive for being brave enough to let a room of designers and devs loose with your still beta tech!


Below is a short video documenting the day!

Ink Hack! from Moving Brands® on Vimeo.

Bike for Sale – Nottingham Cruiser

Bike for sale

I’m selling the first bike that introduced me to the best way to get around London.

In brief

  • £180 o.n.o. for the bike including lights and locks
  • Raleigh Panache (1980s mixte frame with dual down tube)
  • Frame (seat tube) is 21″ (53 cm), but as it’s a mixte frame, you don’t really need to worry about the standover height. I’m 5’4″ (162cm) and this bike is a little bit too big for me. But certainly test ride it first.
  • Recently fully serviced at London Bike Kitchen by me
  • For collection from Hackney
  • Contact me at with any questions, viewing requests, or offers
  • New/replaced items in the two years I’ve owned it
    • Rear wheel
    • Front and rear tyres
    • Chain
    • Headset
    • Handlebars and grips
    • Brake levers
    • Brake cabling and housing
    • Gear cabling and housing
    • Saddle

Bike’s Known History

I bought this bike (then named The Pink Lady) from Re-cycling in Elephant & Castle in the summer of 2011.  I strongly discourage you from ever going to that shop.  I certainly paid too much for the bike which they claim they fix up before selling on.  They definitely didn’t do that with this bike and their customer service was just abhorrent.  At that point I knew nothing about bike maintenance and didn’t know that it was in pretty poor shape.  I ended up taking it to Bike Works for servicing about 6 weeks after I bought it.  I got a puncture about 8 months after that and had the rear wheel replaced at Cycle Surgery when they fixed the puncture (I couldn’t even change a tyre at that point in my cycling maintenance knowledge…).

The following summer I bought another bike that was a bit zippier (Phil) and The Pink Lady went into storage at my flat.  I’ve since learned a ton about bicycle maintenance, thanks to the London Bike Kitchen.  I’m working on building a new bike (just got a Surly Cross Check frameset for a steal!) and can’t justify keeping The Pink Lady. I took the BYOB (Build Your Own Bike) course at the Bike Kitchen this past June.  I dismantled the bike, cleaned and replaced components as necessary, and then put her back together.  I swapped out the drop bars with their horrible brake levers for sit up and beg bars.  The new saddle was sitting around the Bike Kitchen forever and looks like it belongs on a cruiser, which inspired the new look for the bike.  I think it’s now the lovechild of a 1980s Raleigh bike and a coastal cruiser, so The Pink Lady has been rechristened The Nottingham Cruiser. (Raleigh was founded in Nottingham.)

Frameset on stand

The bike during the BYOB course at the London Bike Kitchen.

It comes with front and rear fenders and a rear rack.  I think this bike would work well for commuting and general errands around London.  That’s what I originally bought her for and she did me proud.  I think she’s now in the best condition she’s been in for a decade.  I’m selling her for £180 o.n.o. and including the lights and locks I originally bought for her.

Included lights and locks

Locks and lights included with the bike.

Installation at Tate Modern

I’ve been working with Melissa Matos of TRUSST and Vase to create a jacket that projects multiple viewpoints from the wearer onto the walls of the Tate Modern’s South Tank as a part of Hyperlink. Jacques Greene will wearing the jacket during his performance from 8:30 on Friday.

The jacket is from Rad Hourani’s collection and Rachel Freire has been working with me to integrate the tech into the jacket. I’ll post more details about the build process after the performance.

More info about the event can be found at the Tate website and on Wired.

Campus Party Berlin and Music Hack Day Reykjavik Hacks

This is long overdue, but this past August I attended Campus Party Berlin and in October I participated in the Reykjavik Music Hack Day in Iceland. It was my first visit to Berlin and I’d also never been to Iceland before – and late October is not really the best time of year for a visit – but I loved it and can’t wait to go back to both places.

Campus Party was a weird experience. It’s an overgrown LAN party that has turned into a conference. My strongest associations with LAN parties are from high school where my male friends would hold 24 hour LAN parties at each other’s houses playing various video games in their parents’ basements. Girls were explicitly not allowed to attend and were never invited to play. Campus Party wasn’t a a complete throwback to those days and the organizers had tried to better accommodate a variety of participants. Though I know the intentions were good, the execution was just awful.

Leading a Codasign Arduino workshop at Campus Party.

Leading a Codasign Arduino workshop at Campus Party.

I attended Campus Party to lead a workshop on Arduino and to give a talk. The workshop was meant to be for 20 and ended up with about 60, but everyone had a good time and I hoped learned a bit. When I proposed to give a talk, I was asked to give it on the “Women in Tech Day”. I was a bit confused as I didn’t propose a talk that had anything to do with gender, but it was clarified that they were trying to fill all the parallel stages with women speakers on the same day. I know they were trying to increase visibility, but it ended up creating a ghetto. As a result, there were almost no women speaking the rest of the week and I had to miss several other women speakers because of my own talk. I even missed the networking event set up by the Berlin Geekettes as it was away from the venue and against my speaking slot (meaning also that most women went to that event and not my talk). I know it was an attempt to increase the visibility of women in tech, but I think it ended up worse than if they hadn’t bothered at all.

Anyway, my slides for my talk:

During Campus Party Soundcloud hosted an Audio Hack Day. It was very small, just 11 hacks, but that was nice change from the huge attendance of most Music Hack Days. After the hack presentations there was a Q&A session for the audience and hackers to discuss the hacks in more detail while the judges deliberated. I made a doorbell that plays a different doorbell sound from Freesound (and thanks MTG for the headphones!). The full hack listing is up on github along with the code.

View from the whale watching boat outside Reykjavik.

View from the whale watching boat outside Reykjavik.

The Iceland Music Hack Day was one of the best organized hack days I’ve ever attended. Much credit to the organizing team! The hack was located in a local university which also hosts a hack space in the basement, Hakkavelin. Having a hack space and its facilities so close to the hack day was great and gave physical hacking a much bigger presence than it would have otherwise had. My team for my hack ended up including two lovely lads from the hack space – Gummi and Jason.

Reykjavik viewed from the walk to Reykjavik University.

Reykjavik viewed from the walk to Reykjavik University.

I brought along something like 30m of digitally addressable RGB LED strips leftover from a previous project. Each LED can be programmed and controlled individually to be any color. I didn’t have grand plans for them when I arrived, but inspiration struck for our team when we combined the LEDs with a coat rack (and we weren’t the only coat-rack-hack).

Testing LED Display from Becky Stewart on Vimeo.

We created a makeshift LED panel by draping and taping the LED strips onto the coat rack and diffusing the light with napkins from the breakfast buffet. We then controlled what the lights displayed via Processing and an Arduino communicating over serial. I wrote a little Processing sketch that queried The Echo Nest for artist images and then let you browse them and select one. It then was sampled to fit on the “digital poster” of LEDs.

There were a couple issues that could have been sorted with a bit more time, but we found a compelling demo image and it was good enough. The displayed images consistently came out too red. I think this could have be calibrated into submission, but the sampling method I implemented was incredibly simple. I think just a touch more sophistication in the algorithm would have gone far. But Dark Side of the Moon saved the day.

Wallify – Music Hack Day Iceland 2012 Hack from Becky Stewart on Vimeo.

Badgify at MIDEM Hack Day 2012

This past weekend I participated in a Music Hack Day-esque event. It’s not quite a regular hack day as it is not an open invitation – you have to apply and have attended a hack day before. It’s because it’s a higher pressure event and you’re expected to output a quality hack with a good demo by the end of it for the music business conference attendees. The hack day is also much smaller – 30 people instead of 100+. The result was that it was easier to meet the other hackers and the demonstrations went just amazingly well. Everyone was well spoken and gave a clean demo.

Rebecca Stewart
Photo by Thomas Bonte

I worked with Suzie Blackman to produce Badgify. It was an Arduino and Android hack inspired by an Internet of Things approach. There are many ways to broadcast what you are listening to: Spotify,, Facebook, This Is My Jam, and so on. But all of those services require online connectivity for others to learn what music you are listening to. Our hack lets you share what you are listening to with others in the same physical space as you. Using Bluetooth, your Android phone can communicate with a LCD screen “badge” that you can pin on your coat or bag. It displays the artist you most recently listened to (and scrobbled to

Below is the video of our presentation and a video of the badge and app in action. Our presentation is about 37 minutes in.

The hacks have also picked up a little bit of press.

I’m really glad I attended. Last year’s event was the first MIDEM Hack Day and it was invite-only; there wasn’t an application process. I was vocal in my disappointment in conducting an event this way and was happy that an open application process was adopted for this year. I wholeheartedly encourage you to apply next year.

Soft Circuit Singing Pig with Wigs – Part 4 Construction

Pig in black wig

The patterns for the pig and all the wigs are from Knitting Mochi Mochi by Anna Hrachovec. The knitting of the soft circuit pig was largely unaltered from the original pattern. The main adaptation was that I needed to access the inside of the pig. The original pattern knits the pig from tail to snout and stuffs the pig before casting off and closing up the body. I added an opening and a flap to the underside of the pig by working the body flat instead of in the round for the section between the increases and decreases. I cast on 5 stitches at the end of the row and cast them off again before joining the body in the round and continuing on to the head. This gave me a flap so sew snaps to create a clean closure.

Animation of the pig being knit

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