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  • danSelden 3:49 pm on November 4, 2011 Permalink | Reply  


    Well… the protoPumpkin was off to a great start despite being fairly different than it’s original concept.  Instead of moving panels, I used one servo motor inside to spin a disk which held the various LEDs.  An IR sensor on front would “agitate” the pumpkin, sending the pumpkin from a state of rest (breathing red LEDs) to a state of agitation, a swatch array of LEDs spiraling around its center. After a few loops it would return to its resting state. In addition, the stem acts as a potentiometer, spinning the disk and creating an even more dynamic effect on the front.  See pictures and videos.

    Unfortunately construction was far from perfect and I ran into some major obstacles. Some of which were not completely apparent until final assembly.  The code worked perfectly… but due to the size of the disk, a bizarre servo, and a poorly constructed internal structure (due mainly to the challenges of working inside a pumpkin), the disk and soldered wires kept snagging on each other, eventually tangling, destroying crucial pieces of the pumpkin. Without a functioning IR sensor or the breathing lights… protoPumpkin has unfortunately been reduced to an array of colorful LEDs and a finicky servo motor. For now I’m content to consider it a prototype.

    [update] after poking around during class, I discovered a questionable soldering connection for the sensor. Excited, since for some reason the red lights only work if the sensor works, I figured if the connection was made everything would be back up and running… and sure enough after clipping the ground cable to the sensor and resetting its contact with the ground wafer, everything came back online.  Still had obvious issues with the spinning disk and sure enough after a few demonstrations, two more wires were torn from their solder (once again killing the sensor and an additional LED). It was a great first run though and a great learning experience in terms of building within a decaying fruit.

    and my code:

    #include <Servo.h>
    Servo myservo; 
    int potPin = A1;   //analog pin used to connect the potentiometer
    int val;  //variable to read the value from the analog pin
    int timer = 500;
    int sensorPin = A0;
    int sensorValue = 0;
    int ledPin = 11;
    int brightness = 0;    // how bright the LED is
    int fadeAmount = 3;    // how many points to fade the LED by
    boolean arraySwitch = false;
    int pinArray[] = { //array of pins for colorful lights
    int counter=0;
    int count=0;
    void setup () {
      Serial.begin (9600);
      pinMode(ledPin, OUTPUT);
      pinMode(sensorPin, INPUT);
      myservo.attach(3);  //attaches the servo on pin 3
      for(int count=0; count<8; count++){
        pinMode(pinArray[count], OUTPUT);
      delay (2000); // it takes the sensor 2 seconds to scan the area around it before it can detect presence.
    void loop (){
      Serial.println (sensorValue);
      val = analogRead(potPin);  //reads value of potentiometer
      val = map(val, 0, 1023, 0, 179);  //scale it to use with servo
      sensorValue = analogRead(sensorPin);
      if(sensorValue > 160){
        arraySwitch = true;
      if(arraySwitch == true){
        if(counter >= 5){   //control how long agitation lasts
          arraySwitch = false;   //turn led array off
          counter = 0;   //reset counter
          brightness = 0;   //reset brightness
         fadeAmount = 5;    //reset fadeamount 
      else {
    void lightFade(){
      int counter = 0;
      for(int i=0; i<10; i++){
    void lightGlow(){
     analogWrite(ledPin, brightness);
      brightness = brightness + fadeAmount;
      if (brightness == 0 || brightness == 255) {
        fadeAmount = -fadeAmount ;
      // wait for 30 milliseconds to see the dimming effect
  • danSelden 4:23 pm on October 28, 2011 Permalink | Reply  


    The concept was actually derived from the likes of the Google Chrome icon… a metal sphere with an “eye” in the center. The pumpkinRobot won’t do anything super amazing and at first glance will seem to only have an eye with a pulsating internal light.  However, upon its detection of someone’s physical presence, it’s light will immediately turn flashing red as panels emerge from it’s sides with flashing LEDs.  After some time the panels will recede back into the form of the pumpkin and the internal light will return to its normal state.

    2-3 Sentences about the most challenging and most interesting aspects of the project:
    This has been difficult to build… and while I have built out the circuits for my RGB LEDs (the pulsating interior) and the panel LEDs… the other mechanics have been difficult. I’ve been testing with a button switch but plan on changing the trigger to a sensor once everything works.

    The panel mechanism has been extremely challenging. At first I decided I would need servo motors to push and pull the panels into place… after talking with peers I decided a linear actuator (piston like screw pump) or a solenoid pump would be better since they operate in a single direction and would be easier to integrate into the pumpkin innards. Unfortuantely linear actuators start around $100 and the solenoid pump I picked up is too small to really do what I need it to. Thus, I am back to servo motors… and continuous ones at that, so I need to figure out how to map the range I need and find a way to engineer the push/pull mechanism. (YIKES).

    The only other trouble I ran into was with the RGB light cycle.  While the cycle works fine… breaking out of it mid-cycle to switch into a flashing red display has been difficult and I’m still troubleshooting. Even by including break statements within the cycle code, I was only able to interfere at certain points but would not be able to kill the actual loop.  I hope to resolve this soon or I’ll just include a different mechanism.

  • danSelden 8:35 am on October 20, 2011 Permalink | Reply  

    R2D2 Pumpkin!!!! Amazing 

    Had to post this… came across it on youtube while researching sound recording things…

    • rachel 4:50 am on October 21, 2011 Permalink | Reply

      okay that makes america’s obsession with halloween 100x cooler!!!!!!

  • danSelden 12:45 am on September 22, 2011 Permalink | Reply  

    Maker Faire-steamPunked 

    VASS with War Machine
    Jacques Laroche

    Description: The VASS (Video Audio Synthesis System) is a real-time Arduino powered visualization system which converts analog audio into data a computer monitor can display.
    This music to video system was just super cool… hooking up an old school beat machine to an Arduino and a monitor. The ability to create visuals through different combinations of sounds is very satisfying… offering a new dimension to an immersive sound experience. I can’t help thinking about its application at live shows where people and musician alike can have an influence on the sound and visuals around them

    Spinning Drum Machine 1
    University of Amherst ECE

    Description: The SDM1 is programmed via marks on small discs.  When light is blocked by an opaque mark, the chosen percussion instrument sound is played.  Developed for a Middle School outreach program called Circuits and Beats.
    This was another great project developed to be built and used by Middle Schoolers… it’s super cheap to assemble and the disks which act as the rhythm makers can be easily created by students.  I thought this was generally a great way to expose younger students to basic circuitry and computation… while at the same time pushing them to break out a sharpie to come up with the most imaginative beat combinations.  No two designs are alike, and thus kids are encouraged to explore their creation in a very hands-on way.

    Matt Parker, Albert Hwang, Elliot Woods

    Description:The Lumarca is a display that renders true 3d volumetric content.  Due to the custom designed string lattice, the project can illuminate any point on any string.  This cost-effective, scalable, and customizable solution is drive by a frequently updated open source library.
    This was hands down my favorite installation… being able to project a 3d visualization onto an array of strings creates a tangible experience that seems to offer great potential for informational displays… bringing a vast 3d scape of data points into the physical environemnt.  The depth really brings life a screen cannot capture… especially when you’re able to walk around it. The only drawback is it must be used in a dark environment… and it’s incredibly sensitive to any alterations to the alignment of the strings.  Other than that, I’m tempted to actual get a starter kit they’ve developed and give it a shot.  I included an additional video that showcases some other functionality.

  • danSelden 4:39 pm on September 16, 2011 Permalink | Reply  

    Whutt-Up P-Comp 

    Hello world!

    I’m Dan and my background is in Landscape Architecture and Urban Planning.  I have become increasingly fascinated by our digital world and the integration of new media technology within our built environment. How can a space, connected both physically and virtually, enhance the role of the public realm?  While studying landscape architecture and the city were a great foundation for these interests, they ultimately prepared me for practice and not exploration. By entering the MFADT program I hope to continue to refine these interests and push my fascination with design at the intersection of architecture, biology, social interaction and computation. I think P-Comp will be a good place to build the skill set necessary for this exploration.

    My favorite toy as a kid was hands down Lego… the possibilities are endless.

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