Physical computing |

Sound Fungus

By martin.lukac@iaac.net | Published: December 3, 2012

The aim of the project was t produce sound by using light as a stimulus. In Arduino language we are using five peizo as actuator and photo light resistor as external sensor. Below is the testing image and bread board view of the circute.

We gave it a fungus mushroom like shape, in which each fungus is rising out a common base made up of sand acrylic glass, which houses the Arduino and the bread board. Each fungus ends we an inverted aluminum cup, which not only gives it a fungus mushroom like look but it is also acts as an amplifier and conceal the piezos.

Posted in Furqan Habib, Martin Lukac, Physical Computing | Comments closed

The dear drawing machine is almost there..

By Moushira | Published: December 2, 2012

So now the dear drawing machine is alive, watch her in action below. The darker the light the higher the resistance and thus the faster the speed of the motor. This machine is designed to be hanged on the wall to react to people passing by. If you passed by, or stand in front of it, it will start to draw according to the level of shade you project.

This is a very simple application of using a variable resistance (in this case a photoresistor (LDR)) to change voltage via PWM. Main circuit components are an Arduino UNO, LDR a 10K ohm resistor, a transistor, and a motor, and thats it. . The variable resistance is read using AnalogRead, its value is fed into the transistor base pin via PWM pins using analogWrite, and thats it for the voltage to change according to light making a difference in motor speed. Several manipulation could be done afterwards, starting from assigning different values of light resistance sensitivity to each motor, all the way to making smart moves by designing code conditions according to serial read values from serial port. As you see, the design is simple but building the machine has some mechanical challenges starting from motor alignment to adjusting all the pieces together. I had a very successful first demo (ask Alex and the group –they witnessed ) now I am providing better motor support and eliminating wiring connections, after that I should work on improving the code for smarter reactions.

Posted in Moushira Elamrawy, Physical Computing, Uncategorized | Leave a comment

final: north bracelet

By antanaityte.gerda@iaac.net | Published: December 2, 2012

Here’s the final prototype of north bracelet. During the process I’ve learned a lot about electronics (thanks for Alex). Here are some core hints:

For this application input was tilt compensated compass (CMPS10), outputs were 3 high luminosity leds.
First prototype was made on breadbord to check how it works and to program arduino fio.
To make it portable the circuit had to be replaced and soldered on smaller breadbord.
There were few tricky moments: first of all, because of different voltage, leds didn’t want to shine enough bright. Transistor, which was helpful using power supply from computer appeared useless with lithium battery. The circuit was effected by removing it.
Reflecting tape was used to increase brightness of leds. But everytime I sticked tape on panel, leds used to stop lightning. It appeared that tape worked as well as the conductor. To solve it I put some extra isolation on metal parts of leds.
I had to change some components’ positions and cut out part of bread bord to place everything into the box. And finally it worked.
Arduino fio doesn’t have usb port for programming. It requires special cable with pins.

Below you can see pictures of the process and final result, video and some technical data as well.

final prototype: