How to make an interactive canvas with conductive ink and animated projections.

Interactive canvas with projected animations

I’ve wanted to experiment with projections for a while and decided to mix that with conductive ink to make it an interactive experience.

I got inspired by this work by Sofia Aronov and wanted to build something similar.

Projection on canvas

Here’s the list of material you need if you want to build something like this:

• Canvas
• Conductive paint
• Ruler
• Pen
• Rubber
• Paint brush
• Masking tape
• Blu Tack
• Nails
• Bare conductive board
• Copper tape
• Projector

Material needed to build an interactive canvas

The way it works is that the Bare Conductive board has 12 pins (the 12 gold-colored things on the side of the board) that can be used as triggers. Usually for sounds, but can also be used in our case to trigger animations.

Step 1: Preparing the canvas.

I started by drawing squares on the canvas using a ruler and pen.

I used masking tape on the inside and outside of my squares to allow me to paint freely and not be worried about going over (I kinda somehow went over anyway…).

Canvas with masking tape

After letting the paint dry, the result looked like this:

Let the paint dry before removing the masking tape

Remove the masking tape to see your squares on the canvas.

Before moving on to the inside of the canvas where we’re gonna add the board, we need to upload a sketch on it and use MadMapper (the projection mapping software) to map the triggers from the board to the animations we want to display.

Step 2: Use MadMapper to map the triggers to animations.

First, download the Arduino IDE if you don’t have it already.

Then download the Bare Conductive Arduino plugin installer you can find under step 3 of this article, unzip it and launch it to finish the installation.

Once you’ve re-launched Arduino, plug your Bare Conductive board to your computer, make sure the on/off button is on, go to File > Sketchbook > Touch board examples > Midi_interface_generic and upload the sketch to your board.

Upload the sketch to your Bare Conductive board

We upload this sketch to the board to be able to use the MIDI communication protocol to trigger animations based on which pins of the board we’ll touch.

Once you’ve uploaded the sketch, download the MadMapper software.

When you launch it, the base interface should look something like this:

Base interface of MadMapper

To create my animations, I wrote sketches in Processing and then saved them as .mov files but if you have short videos already, that can work too.

Drag and drop your first animation in the middle and it should appear, along with some parameters you can change.

Screen changes when you drag & drop an animation

At the bottom right, where there are a few options next to “Mode”, select the 2nd one so your animation plays once and does not loop.

Once this is done, we need to map that animation to a certain pin on the board. To do so, go to Controls > Edit MIDI controls.

Then, when you’re ready, at the bottom right, next to Play, click on the “go to beginning” button, the one that looks like this:

It should turn grey to show it is ready for you to touch a pin on the board.

When you touch the pin you want to map to that animation, go back to Controls > Edit MIDI controls to exit the edit mode.

When you touch that pin again, you should see the animation play in the software.

Repeat that with how many animations you have.

Now that the mapping is done, we need to attach the board to the inside of the canvas and link it to our squares we painted.

Step 3: Assemble the board, canvas and projections.

Take your canvas, add nails through the paint to be able to use it with copper tape and the Bare Conductive board on the inside of the canvas.

After doing so, your setup should look something like this:

You should now be ready to move on to the last part, the calibration.

Step 4: Calibration of the projections.

To calibrate your animations on top of the canvas, place it on a wall or on a table, plug the board and the projector to your computer, turn everything on and go back to MadMapper.

Simply go to Output > Full Screen mode and touch the part of your canvas that has conductive ink. You should see the animations being projected but probably not calibrated properly. Exit full screen mode, move your animations around and return to full screen mode.

Repeat until it’s calibrated right.

Hopefully, everything should be going smoothly.

Animation calibrated on canvas

It looks better if you can turn off the lights around you. I couldn’t because I was working on this in our office and the lights are activated by motion sensors…

I tried again with a darker space and it still wasn’t super great but better.

Next step would be to paint more interesting shapes and create nicer animations!

Hopefully this is helpful and if you end up building something similar, please share! :D