Capacitive Sensing + Open Frameworks + SPACEBREW
This is a step-by-step on how to connect Arduino to OpenFrameworks using Spacebrew.
More specifically our project focuses on the awesomeness of Capacitive Sensing to alter OF projections to create an awesome tactile experience!
What the process will involve:
Arduino -> Processing -> SpaceBrew -> OpenFrameworks
What you will need:
Anything conductive you want to detect capacitance with!
Step 1: Capsense with the arduino
First you will want to set up your Cap Sense circuit.
You can create as many inputs as there are digital pins (If you wish to have more you will have to implement a multiplexer TUTORIAL LINK ).
The Cap Sense library allows you to turn two of the Arduino’s pins into a Capacitive Sensor i.e. Sensors that can detect the electrical capacitance of the human body!
This allows us to create interesting touch sensors to send input to the Arduino.
Setting up the circuit:
- The first diagram shows the general set up of circuit with one input. You will want to connect the resistor between two pins, here we have done it between 2 & 3.
- Then connect which ever conductive material you wish to be your sensor to the resistor on the pin 3 side.
- We are keeping pin 2 as our common send pin which will be used for all our sensors.
- Then set up all other sensors in the same way except all having one connection to pin two and then the next free digital pin (See diagram 2)
*** It can be good to just test if it is working by having an exposed wire as your sensor!
Download the CapSense library here
After you have downloaded the library copy the folder into your Arduino library folder.
You can download our code here
(ALL code is commented
Step 2: Our Capacitive Sensors!
You can detect capacitance with anything conductive!
We wanted to create something tactile, interesting and weird for the user to touch so we implemented some crafting techniques! We made Soft Circuit Pom Poms.
Soft Circuit Pom Pom Materials:
2. Conductive thread
** by distributing the conductive thread with regular threads and resistant materials it creates greater connections when you grab the ball or run your hand through it. IE. allowing more electricity to connect to the sensor, giving a greater value output.
1. Chicken wire
2. Plaster of paris
** the plaster of paris created a small barrier of resistance between the wire and the hand, meaning that values wouldn’t be picked up until you ran your hand over the object.
For more detail: Capacitive Sensing + Open Frameworks + SPACEBREW