. m i n . . . i t p i n g .: May 2006 Archives

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May 31, 2006

ShadowBox Update

G will be out of town for a few weeks. We will continue and finish this project this Summer.

Posted by min at 09:22 AM | Comments (0)

May 14, 2006

The UnsweetCandies at the ITP Spring Show 2006

Thank you Jane Oh for all your support, thank you everyone for coming and trying the candy jars out!

Jane and I worked hard until the final day to the Spring Show 2006.

We had simplified our CandyStore Project into just three different interactive candy jars that each had different personalities. We also got bigger, plastic jars to allow us to give more space to hide the hardware under the candies. All three were triggered as one would dip their hand into the jar, for a candy.

We came to three big candy jars that would glow, scream and pop up as one put their hand into them.

Since they were all triggered by touch, we decide to use the QT 113, one channel touch sensor. QTs are very finicky to work with, in that, the sensitivity differs drastically depending on the setting and the electrode; the sensing part. The electrode pin is most effective when placed closest to the QT113 as well.

We had first attempted to try everything out on a breadboard, got it to work then would transfer the exact layout onto a perf board, realizing that it no longer had the correct sensitivity. We decided to set up everything as it would inside the jar and went from there.

The solenoid module was hard in that it required a much higher voltage and amperage than what the breadboard setting could provide. We tested using a bench top power supply, and noted that with about 24Vs, we were able to get the correct “popping” motion that we wanted in our jar. The QT would sense the touch, then would trigger the solenoid. This part is done using the PIC. Since the PIC runs off of 5Vs. we were to use TIP120 to send data from the PIC into the TIP120’s base pin, sending it a high and low.

The glowing of the DOTs essentially came to PWMing the individual LEDs embedded inside the GumDrops. This also required high lowing the base pin on the TIP120.

The screaming jar gave us complications. We first used a 20 second voice recording module from Radio Shack. We hacked into the play button the module. It was the one similar to the one found in the WalkieTalkie from the UBi.ach Project. The pressing button has one strip of conductive metal that completes the circuit as it is pressed on. Since the module is also separately powered by a 9V, we used a TIP 120 here as well. We got it to play back as touch was sensed but with time, the board would just get hotter and we burnt out two of the boards. After seeing our frustration, Todd suggested that we work with an MP3 Player instead, simply turning it on and off when the sensor was triggered. We used a relay to turn the sensor on and off. The exciting part of all this was the usage of the plasma sheets. We attached the sample sheet around the jar, instead of using separate speakers inside the jar. The screaming recording came out really nicely with this output.