Sensing and Responding to the Analogue World

Have you ever wondered how motion sensors in a gallery installation or museum exhibit work? How does your movement trigger a video to play, or the lights to dim, or make things move? Im always curious about the mechanics of interactive and immersive experiences, and in the final week of summer school at the Copenhagen Institute of Interaction Design I found out how action gets mapped to data and how data triggers motion.

I know, sounds like a wild and crazy week, huh?

Doing a pressure sensor test on the Arduino platform

Experimenting with a pressure sensor, two copper strips on foam, and an Arduino board.

Let’s Get Physical, Physical!

The focus of the third week’s course, Physical Computing, was to look at computation using Arduino. What is Arduino, you ask? Used as a way to work with microcontrollers, Arduino is an open-source prototyping platform that enables physical interaction with technology and objects. It uses sensors and microcontrollers to translate analogue input to a software system, which in turn controls electro-mechanical devices. Arduino is used for art installations, communication devices, costumes, medical equipment and a multitude of interactive environments that you probably encounter everyday. Some great examples of projects using physical computing are Danny Rozin’s Wooden Mirror, Fabrica’s Tuned Stairway and the Melody Man Electronic Designer Toy by Carla Diana.

Our instructors David A. Mellis and David Cuartielles (two of the founders of Arduino), began the week by posing a few big questions: how do we map from action to data by using input to computation to output? In the context of building products, what do we as Interaction Designers need to sense and actuate interactions? How do we power them? Communicate with them? build them? We were going to discover the answers to these questions while making things spin, beep, blink, vibrate and propel using our laptops, Arduino and electrical hardware.

Projected Arduino Code

It’s gonna be a geeky week. Arduino code for making a LED bulb blink endlessly.

Following a crash course in electronics, we began tinkering with the Arduino board and software, playing with motion and pressure sensors, and servo and stepper motors. Although the learning curve for me was steep (I don’t come from a science or computing background) as I explored the connection between code, algorithms and interaction I began to get excited about the potential for using Arduino in personal projects, exhibit design and prototyping.

Hacking the Radio

After completing a few small projects over the first few days, our final project brief was to reimagine the radio, to rethink the radio user interface and build a prototype of the radio as an electronic device. We had three days to invent, test, and prototype our designs. We split into small teams, and my partner Peng and I spent the first afternoon brainstorming, sketching and making rapid-prototypes of our initial ideas. Our final design, an interactive radio named Chi Sounds, is shown in the video above, but Ill tell you a little bit about the design process.

Sketches from a brainstorming session that show ideas for reimagining the radio

Peng and I began to explore the idea of a personalized radio, where the user could customize the receiver to a few favourite stations. Some of our early ideas explored a two-station radio in the form of a shaker or hourglass, and a base station with opposing switches. A dice, or cube, with a unique station on each side also seemed cool at the time. We were thinking that interaction with today’s radio should be minimal and intuitive, involving just a few basic gestures such as pulling, tapping and flipping. We started to think about an elegant object in the home or office that was easier to use than a digital player.

Radio rapid prototype made from dense foam on a lathe, showing two stations

One of our rapid prototypes for a programmable two-station radio based on an hourglass shape and turning motion. You could program, say, a jazz station on one side and a news or rock station on the other. Once we held the prototype it suggested a barbell, not the look or feel we were going for, although we did joke about switching to a workout radio concept.

The most compelling of our ideas was a kind of radio cube, where the user could select a station for each side of the cube. We could incorporate an accelerometer to sense the rotation of the cube, and an infra-red sensor for adjusting volume. The cube could be made as a mitred wooden box with a friction-fit lid, and any detailing could be made with the laser-cutter. We divided up tasks. Peng, a UX designer at Nokia, took on the computing work, and I delved into making a mitred wooden box so that I could build on skills I’d learned during the previous week in Physical Prototyping class.

Making the Chi Radio physical and computing prototype

Above, clockwise: Peng works through an Arduino challenge. The coloured circles and the speaker "mesh" were cut on the laser cutter. The mesh pattern allowed the infra-red sensor to fit into one of the openings. The Radio workings - microcontroller, sensors, amplifier, speaker and battery - were zap-strapped together and glued onto the speaker mesh, which doubled as the box lid.

Using the hot wire cutter and some glue, I quickly made a styrofoam box with a fitted lid. Meanwhile, Peng tested several options for sensors that would bring the radio to life. Using the prototype, we were able to quickly adjust the size of the radio so that the hardware would fit inside and it was comfortable to hold. A couple of days of design intensity followed, but we referred again and again to the foam prototype to develop the radio concept, discuss usability problems and solve construction glitches. From the computing side, challenges with determining numeric inputs for the sensors, tuning the FM chip and the delicate work of soldering were an all consuming task for Peng.

opening the lid to reveal the Chi Radio electronics. Photo by David E. Mellis

By Friday afternoon we put the finishing touches on the radio, zap-strapped the electronics and battery together and fitted the lid onto the box and made our final presentation to the class.

Demonstrating the Chi Sounds volume control. Photo by David A. Mellis

Peng and I demonstrate our Chi and play with the volume control at the final presentation.

My classmates radio projects were incredible, some of them were: Raydio, and a radio that you throw balls at to switch stations, a colour-sensitive radio, to keep pests away try Random Radio, and one with long-distance vision was Telescope Radio, and a few others here and here.

Thanks to all my classmates and to the two Davids for an action-packed week.

Top and final two photos by David A. Mellis on Flickr