Today was a good day. We finally got the electromagnet working and linked up to the Arduino. First thing we got to do was to get the LED to be lit at different brightness depending on numbers from an RSS. To vary the numbers for testing we used a random number generator shown in the video above.
Then we got around to using the Relay which was the next hurdle. Due to the power needed for the electromagnet to work we had to have it in an ‘always on’ setting linked up to the 9V battery (as a separate circuit to avoid blowing up the Arduino) and use the Relay to break the connection. After numerous tests and some help from Simon we managed to get the Relay to break the connection so the electromagnet would be broken in the circuit and the power would be lost. As the Relay only works ON/OFF we cannot change the charge to fade in and out. So the best way to use it is to pulse 1’s into the Relay to turn the magnet on and off as shown in the video above picking up a coin. The Arduino will pulse different speeds depending on the RSS output to create a ripple effect in the Ferrofluid.
Lastly before we called it a day we tested it with some Iron Filings and it managed to pick them up fine as shown in the picture above. Now tomorrow we will test it with a tiny amount of Ferrofluid that Lee has lent us, film it and have it ready for the presentation next week.