Physical Computing

Presentation Day Video

2005-08-05T06:50:00.000-04:00

Presentation Day Video!

Video...no sound

2005-08-03T22:29:00.000-04:00

Here is the video we originally took. I didn't realize none of the sounds we were producing wasn't getting recorded. We need better speakers. The sounds you are hearing is just ambient noise. I'll try to get a better video up tomorrow.

Where's the sound?

Final!

2005-08-02T23:07:00.000-04:00

It works!

We had a few bumps, but have a good working prototype.

We have our circuit, which looks like the MIDI setup from before but with a connection for the photocell. The circuit is housed in a protective box, which is an old plastic VHS case with some holes Dremelled out. It’s from a Jean-Claude Van Damne movie in case you were wondering.

Circuit in protective case

For the gloves, we used two high-heat resistant (425 degrees) gloves we bought from K-Mart. We didn’t actually need high-heat resistant gloves. These were just the only ones that fit with a good amount of maneuverability.

On the left hand, we have the contacts on the fingertips and the orb. The orb is secured onto the glove with hook and loop clasps, aka Velcro. There are two contacts per finger; red for power and blue for data transfer. The ground is in the orb. Please refer to previous post for in depth orb goodness. The four fingers (excluding the thumb) control four tones. When the thumb contact is depressed, the four fingers trigger four different tones. On the right hand, there is one contact and that too when depressed, triggers another four tones. In total, we create 12 tones which complete a scale. The contacts are made from a sheet of copper.

Gloves with contacts and orb

Back of hand

In addition to the thumb contact, the right hand also has a photocell within a wire spool. The spool helps to restrict the amount of ambient light that the photocell is subjected to. The photocell controls the pitch of the tone using pitch bending. More info can be found in Lazlo’s Blog.

Glove with contact and photocell

The project came together quite well. It required several test models and test subjects to get to this point. There is still some fine tuning that is needed, but I think it is a good prototype.

Gloves at work

The only thing not pictured is the Korg MIDI synthesizer that we are using to output the sound.

Another note is that we are using two different power supplies. We are using the 4.5V battery pack to power the lights and the 12V to 5V regulator to power the PIC chip.

Final Project, aka Midterm Upgrade

2005-07-28T21:17:00.000-04:00

Upon completing the Midterm, Lazlo and I discussed plans for the final project. We definately wanted something that sounded more like an actual musical instrument. It was decided that we would try to integrate the use of a MIDI synthesizer. In addition, instead of using the same switches from the midterm, we are going to be making a glove/orb switch (refer to pictures).

We put together our MIDI test board and was able to successfully play notes with the different switches (represented by header pins and alligator clips). Refer to Lazlo's code for more details.

MIDI test board

A closer look at the MIDI test board

Now, for the switch we will be outfitting a glove with metal contacts that will touch an orb to complete the circuit. LEDs will be used to verify with the user with button is making contact.

If your hand looked like a bear claw...

Diagram of orb

Bear claw playing orb

So far, we have clustered all of the LEDs, tested that the system will work and soldered together with the help of some perf board. The cluster was tested using a battery pack which consisted of 3 AA batteries and alligator clips. The cluster shares ground and their other end will be connected to their respective metal contact. Note that the "blue LEDs" are not LEDs. The are the incandescent light bulbs off of some old strand of Christmas lights.

LED cluster

Red

Green

Yellow

Blue

Our next step is to find a glove that will be flexible enough to make for comfortable playing of the orb. We're looking into welding gloves or latex dish washing gloves.

Midterm Video

2005-07-21T09:56:00.000-04:00

Video goodness here and code for your viewing pleasure at Lazlo's Blog.

It's DEVO-like!

Completed Midterm Project

2005-07-20T22:57:00.000-04:00

After using Jun as a guinea pig, she gave us some great suggestions as to how to make our controls more user friendly including her suggestion that we use a foot pedal for our play/stop button to mimic playing a piano. Luckily, I had a foot pedal from a drum set. After making the adjustments, this is what we got:

Complete circuit

To make the foot pedal a switch was a bit tricky since basically the whole pedal is conductive. With some strategically placed electrical tape, I was able to make a pretty fancy switch.

Play/Stop foot pedal

Here is a close-up of our breadboard.

Breadboard

We enclosed the photocell to give us the ability to limit the amount of light that was received on the cell which controls the tone that is played. Using a metallic box further helped us get a wider range of values.

Tone photocell in sliding case

My three button switch was reduced to one button. One of the buttons function was redundant so it was removed and the other one was replaced by the foot pedal. For those interested, the funky shaped speaker was taken from a G3.

Note duration/frequency switch and Speaker

Video to be posted. In the meantime, here are some photos of Lazlo demonstrating how the instrument is played.

Lazlo playing instrument (Pic 1)

Lazlo playing instrument (Pic 2)

Desoldering Pump versus Desoldering Iron

2005-07-18T21:35:00.000-04:00

The plan for the midterm was to actually mount the product onto a perfboard. I did not want to solder the chip directly to the board because 1- We may want to build the final project off of this so changes may need to be made and 2- I may accidently melt the PIC while soldering. So I went to the junk bins and scavenged for a chip holder that would fit the PIC.

I found one on some old printer. I then began desoldering with the use of a soldering iron and desoldering pump.

Desoldering Pump

After 2.5 hours: I bent most of the pins, half the pins did not come out with the holder, and the pins that I was not able to reshove into their holes I either broke or lost. It was basically unusable.

Chip Holder #1

My progress was not looking too good. I just wasted several hours on something that I could not use or salvage. I decided to rummage through the junk pile again and found another pin holder. I took that home and bought a desoldering iron from Radio Shack. It's a combo iron with the pump.

Desoldering Iron

Not only is the iron superior with the ease of use where I have the ability for one handed use versus needing four hands for the pump, I was able to get faster and cleaner results.

Chip Holder #2

The desoldering iron is definately worth the cost and worth saving the pain of more blisters on my thumb!

Midterm Update

2005-07-14T08:24:00.000-04:00

After seeing a demo using "Processing," Lazlo had the idea of using the photocell to allow the user to pick a note that they want. The user would be able to see the note on a moving scale on the computer screen. To do this, a test needed to be done on reading input and responding with some output. A second circuit was created for this test.

Test circuit

The program ran in MicroCode Studio correctly by changing its output when the input was changed. We are currently stuck on some code in Processing.

In addition, Lazlo mentioned that he wanted a system of 3 switches so that the user would be able to record the music that they were creating, play the music and stop the music, respectively. At first, I thought to use these buttons found on a dismantled portable CD player. After 10 minutes or so of trying to desolder one button, that idea was scrapped. Looking in the junk bin, I found a 3 button switch that Lazlo brought in last semester. It looks like something that would be found in a factory with an assembly line.

Completed Three Button Switch

We first tried to see if we could just test the wires and see what combination of wires would give us connectivity. It seemed that all combinations did whether or not the button was depressed. My next step was to open the case and see what is making it tick. It wasn't making much sense. There were loads of wire just cross-connected in non-logical ways to all the Archer switches. I decided it was best to desolder and start from scratch.

Several hours later, all of the connections were desoldered. Using a multimeter, it was easy to determine that the upper pins were what controlled the switches on/off. Lazlo said he recalled that the buttons used to light up. It seemed to explain what the other pins were used for. Now all I had to do was figure out how to make these connections such that when the button is depressed, the light on the button would come on. Using alligator clips, a multimeter and my circuit from Assignment #2 I tested a few combination of connections before I had it working.

Testing

Finally, I soldered the joints.

Soldered

So now we have the switch we plan on using. We just need to get the bugs out of the code.

Midterm Progress #2

2005-07-12T10:34:00.000-04:00

The code for this can be found on Lazlo's blog.

Magical!

To create the equations for WindL (duration of note), Notea (first note) and Noteb (second note), we first read in their ranges. WindL's range was 30,464-57,600; Notea's range was 19,392-53,696; Noteb's range was 52,800-53,312. The range differentiation seems to be partially caused by the different range of resistance the photocell operates on. We had photocells with ranges from 1K-18K Ohm and then there were some that were 0.9K-4.5K Ohm.

Midterm Progress Video

2005-07-10T22:11:00.000-04:00

As promised, here is video of the photocell receiving different levels of light which causes the sound output to change.

Listen carefully!

Midterm Project Beginnings

2005-07-07T23:35:00.000-04:00

Lazlo and I began discussing what we wanted to do for our Midterm about two weeks ago. To put it simply, we came up with an idea to make electronic instruments. Of course it will have blinking lights because everyone enjoys them, but the bells and whistles will need to wait. We are currently at a point which coincides with the assignments due this week (Assignment #3 and Assignment #4), which is good. This part one should be our Theremin-like instrument. A video is pending. Apparently I've exceeded this week's limit on video uploads so I must wait a few days to post the video. In the meantime, enjoy some photographs.

Pic 1

Pic 2

Lab Assignment #2

2005-07-05T08:01:00.000-04:00

Lab Assignment #2

Upon reading the assignment again, I realized that I skipped part 1. Here are some pictures and video of a programmed PIC to work with a switch.

Switch is off.

Switch is on.

Close up!

video

Amendment to Lab Assignment #1

2005-07-01T16:58:00.000-04:00

Watch video of a potentiometer in action. As the resistance is increased, the bulbs dim. As the resistance is decreased, the bulbs brighten.

Lab Assignment #1

2005-06-29T17:52:00.000-04:00

Lab Assignment #1

I basically have 4 different systems on my board (PIC 1, PIC 2). The first one is the straight forward single LED with 220 Ohm resistor with 5 V input (PIC 3). The second system is the same but with 2 LEDs (PIC 4) and my alligator clip switch. Yes, the red LED is lit. Apparently red doesn't photograph well. Anyhow, you can tell that the LEDs are not as bright as the first system. The next system has 3 LEDS (PIC 5). They appear to be really dim to not even lit. My last system has the 3 LEDs, but with a slightly higher resistance of 330 Ohms and I circumvent the 5 V Voltage Regulator to get an input voltage of approximately 12 V (PIC 6).

Basically what happens is that the LEDs require about 1.5 V - 1.8 V each to work (that multimeter sure is handy), so in system 3 the voltage is spread really thin that nothing can get enough juice to work. That's the problem with series circuits. As you can see in PIC 7 that 3 of the 4 systems don't have a problem running since they are in parallel and therefore each system gets 5 V or 12 V, respectively.

PIC 1

PIC 2

PIC 3

PIC 4

PIC 5

PIC 6

PIC 7