Flux Liverpool is an Arts Festival in the heart of Liverpool which will offer a multi-art experience in the heart of the culture capital!
I have recently worked with a really talented illustrator Rhi Moxon on an interactive printed map that was on display in the Hub at the Liverpool Flux Festival.
Rhi approached me after seeing the Interactive Tools installation at GlynDwr this year.
Rhi has designed and illustrated a beautiful map / poster that shows key locations in Liverpool as beautiful hand drawn images, Rhi wanted the poster to do a little more than just show visually the locations, but also to tell a small story about the locations themselves. Rhi’s poster offers users an insight into the rich history of Liverpool, its building and its people by listening to short snippets of fun information read out by local Liverpudlians.
How was the poster made?
The poster was roughed out with an initial layout, the idea of a central map using a touch system along the bottom was fleshed out so that we could start designing a circuit on the back of the poster that would make up our conductive circuit. First off we experimented with a circuit design that would run from each touch area (or buttons) going to the input of the arduino. To use the conductive ink with Arduino you need a way to create a capacitive sensor, I used the Sparkfun Capacitive Touch Sensor Breakout board connected to the Arduino. You can read about this setup on the Bildr Website .
I roughed out the principle in a sketch book first so I could easily visualize the process.
back of poster circuit
Here is an image of the first circuit plan.
Cap sense circuit
The idea here was that there are the touch points as large circles with a leg coming off of each circle that ended towards the edge of the poster so that crocodile clips could be connected easily to an individual touch point but not interfere with the poster in any way.
Once the circuit was completed and tested with the Arduino, the idea was to sit the circuit behind the poster, each touch point would need to be printed in exactly the correct position behind the poster. To aid the conductivity we decided that the touch points on the front of the poster should be printed with conductive ink also.
conductive ink circuit
After some testing, it was extremely difficult to set the threshold in the arduino at the correct levels. It has to be taken into account the fact that just the movement of air is enough to trigger the arduino if the code was set too sensitive, but obviously if its not set high enough then making a contact on the poster would be intermittent.
Most of the problems I think arose from the quantity of ink that was required to make the entire circuit, the more the ink used the higher the conductivity.
After some trialing of the poster using an ink circuit we went back to the sketch book and decided to experiment using hook up wire from the touch point directly to the arduino. This seemed to be far more stable than using just ink on its own.
Poster Circuit with wire
We installed the poster in the hub, using some hobby boxes to contain the Arduino and the Cap Board, these were screwed to the wall and the poster was attached to the wall with the circuit behind. Unfortunately, I found the Arduino to be fairly unstable with the conductive ink at times it would self trigger and you would have a jumble of audio and other times it was intermittent in the connection at all.
As this poster was installed for a permanent exhibition of 2 weeks the technology side of it needed to be far more solid than it was, at this point it was decided to change the technology. We had seen a new board that has been marketed more for children and quick interactive applications called the ‘MakeyMakey‘ it’s really a simplified Arduino and Capacitive Sensor Board all in one, very similar to the new Bare Conductive board. We purchased the MakeyMakey and were quickly impressed by the ease of use and speed that you could get the project up and running. The Makey doesn’t require any programming knowledge so it was an instant success with Rhi who didn’t have any background knowledge of coding.
The only downside to the Makey is that you have to close the circuit by earthing it, this wasn’t a requirement of the Arduino design so Rhi had to add another button into the design that allowed the circuit to be earthed.