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Category Archives: hacking

Now in the second year, we’re building the design@UL exhibition in Limerick City with a selection of our students’ design work. It’s quite an interesting experience when faculty from computer science, architecture, civil engineering, aeronautical engineering, etc., come together and talk about how to design and exhibition. You would imagine that we’re all singing form the same hymn sheet, but as design can be so many different things, the creative cacophony can be almost overwhelming at times. I think it’s an excellent interdisciplinary exercise and as we learn to work together, new ideas emerge and are negotiated.
This year, the exhibition opens on Tuesday evening, the 28th of May at 18:00 and runs until Saturday the 1st of June. Admission is free, so please call in and have a look, talk to the students and enjoy the creativity.


For Science Day 2012 at UL, we decided to build a fun controller and sound synthesis demo. Over the past few years, we’ve had a number of postgraduate students exploring for example Galvanic Skin Response for artistic expression. It was slightly surprising to see the hype when Makey Makey launched earlier in 2012. I was puzzled that they didn’t seem to be aware of the work by for example Erkki Kurenniemi and Ralph Lundsten in the late 1960s and early 1970s. Kurenniemi’s DIMI-S is Lundsten’s Love Machine.
We were inspired by the original work by Kurenniemi and Lundsten and we designed and built a 16 channel analogue resistance multiplexer. The circuit uses four inexpensive CMOS chips (CD4051, 8-channel mux) and a couple of transistors (connected as a current mirror), connected to an Arduino and then to a laptop running Pure Data (PD). The Arduino controls what two pins that are active at any given time, rapidly scanning the whole matrix of possibilities (there are 240 possible connections, with 16 channels).
LoveMachine++ interface circuit
We then designed a sound synthesis system in Pure Data (PD) with both a spectral synthesizer, taking the parameters from the resistance matrix and doing a reverse Fast Fourier Transform, and a sequencer, where the mixing and filtering is controlled by the resistance matrix.
LoveMachine++ demo setup
We had to explain to the first few students that they had to touch at least two fruits or vegetables to get sound. After about an hour, word was spreading and experimentation flourished, with several students holding on to vegetables, shaking hands, touching foreheads, etc.

A short video clip from today’s demo.

Schematic diagram

LoveMachine++ interface Schematic Diagram

Bill of Materials

Name Value/Type Description Quantity
D1-3 1N4148 Diode 3
IC1-4 CD4051 8 channel analogue multiplexer 4
Q1-2 BC556 PNP transistor 2
R1 560K Resistor, 0.25W 1
R2 220K Resistor, 0.25W 1
R3 47K Resistor, 0.25W 1

Source code

Arduino code

PD patch

[note: I cobbled together a simple communication protocol in the code and patch above. Basically, an ASCII-based fixed packet length with a terminator character, which makes it easy to see and debug]


Some background on Kurenniemi’s work:

Mikko Ojanen, Jari Suominen, Titti Kallio, Kai Lassfolk (2007) Design Principles and User Interfaces of Erkki Kurenniemi’s Electronic Musical Instruments of the 1960’s and 1970’s, Proceedings of the International Conference on New Interfaces for Musical Expression, pp. 88–93.

With the emergence of wonderful audio apps such as Audioboo, it has become a challenge to record outdoors without the rumbling from wind hitting the microphone.
If you get some nice fluffy textile (see my note DIY Wind-jammer for Zoom H1), you can use a similar, but even simpler approach.
Cut textile
Cut a piece of the fluffy textile about 2 centimeters wider than your phone and about twice the length of the “base” of the phone.
Fold and stitch
Fold the textile with the fluffy side in and sew/stitch along the short sides.

turn inside-out, attach to phone
Turn the textile inside-out (so it gets the fluffy side out!)
Put it on your phone and record.

Happy Recording!

It is a real mystery that a lot of people think that touch screen and multi-touch technology is a novelty. Touch screens have a long history, see for example Bill Buxton‘s extensive research on this topic.
In my own work, I stumbled into touch screen research around 1984, while speculating about possibilities to optically interconnect VLSI circuits through optically transmissive substrates. As my own lab did not have the facilities to try out some of the ideas on a micro-scale, we fiddled with normal sized opto-components and circuits, assuming that the principles would scale down if we ever managed to get a budget to pursue this radical idea.
We never found any funding for the VLSI optical interconnects, but we continued to explore the possibilities with the experimental setup, which resulted in the largest touch screens in the world at the time.

Early touch screen prototype, 1986

We were very lucky to get in contact with the local transport company in Gothenburg who gave us an order for three prototype systems. This, in turn, led to contacts with Swedish Rail, via KNM electronics, and a full deployment of our touch technology at all railway stations in Sweden.

One of the first full-scale touch screen for public transport info. 1988

One of the STINS systems, developed for Swedish Rail. 1989.

As my own interest was and remain to make new prototypes, I refocused on making slightly smaller devices that would fit around normal computer screens, CRTs. We succeeded in designing such a smaller system, more lightweight and less expensive.

The VENTRI prototype. A General Purpose Portable Communicator with a touch screen. 1992

This led to explorations of how touch technology may be used by users with different forms of physical disability. We participated in the EU initiative TIDE – Technological Initiative for Disabled and Elderly. In this European collaboration we came to work together with Speech Technology Ltd and Circuits Test and Systems Ltd  at Trinity College in Dublin. The collaboration resulted in a pretty amazing prototype of a General Purpose Portable Communicator targeted at users who could not speak and with various degrees of physical and cognitive impairment. Unfortunately, we couldn’t find funding for any volume production and marketing of the device.

Touch screen for London Underground passenger info. 1993.

Later, I came in contact with Multimedia Technologies Ireland (MTI) in Plassey Technological Park in Limerick and Trinity College in Dublin. Together with MTI, we developed two prototypes of a system for interactive passenger information for London Underground.

My smallest touch screen prototype. Handheld. 1994.

I also started to fiddle with a really small device, a handheld unit. I made one single prototype and tried to show it, in confidence, to a few of the larger manufacturers. The one and only prototype disappeared during one of these excursions and I only have one single photo left of it, from around 1994.

Looks familiar, doesn’t it?

A first sketch of a new custom controller.

  • Sliders fading up and down
  • Knobs for turning
  • Cranks for turning
  • Buttons for activation – perhaps with aftertouch (force sensitive)
  • Switches for turning things on or off.
  • Wheels for turning
  • Squishy things for squeezing

USB i/o, perhaps using OSC protocol.

Build in a flight case.

controller sketch

Over the past few days I have noticed that even without having a browser window or tab with Facebook open, suddenly you get a pop-up warning that the browser cannot authenticate over a https connection. I find this quite alarming as this implies that either, some spyware that I haven’t identified and zapped yet has come onboard the computers in question, or, that Facebook are leaving some extraordinary crap behind until you close and restart your browser, or, that other web sites are trying to exploit security holes in Facebook.

Computers used: MacBook Pro/OSX 10.5.8 and iPad (version1) iOS 4.3.3
Browsers: Safari and Firefox.

Is anybody else noticing this?

(Why OSX 10.5: it’s what I have on one of my machines. I haven’t tested this on 10.6 etc yet)

During the Sounding Object project, we researched and developed new approaches for sound on computers, responsive to physical interaction and easily matched to physical objects. One of the demos was the Vodhran, a virtual Irish Bodhran drum. The performers gestures are tracked using a Polhemus Fastrak 6-DOF electromagnetic tracker in realtime and the sound synthesized in real-time by our sound object models.

This summer, I’m planning to make another version of this, probably the Hodhran – a Hyper-bodhran, using a real bodhran, parts of a Wii controller, an Arduino and a few sensors (such as force sensitive resistors and bend sensors).

>I’m just home after yet another evening’s excellent experiences. The TWEAK festival has had a very positive impact on the city, with the addition of tonight’s SOUNDINGS event. Still, tomorow I need to go and see the TWEAK exhibition in City Hall…