Crow head model

Crow head - shaped chicken wire with xmas-decoration baubles for eyes, skinned with silver gaffer tape
Positive model to be used as a forma over which to apply papier mâché.
November 2011

Head for a pantomime goose costume - part 1

Agreed to make some costumes for pantomime.
Trying to make several bird heads, starting with a goose. A quick while on Google images and I found some great goose shots. First thing is to copy out and draw them a few times. This helps fix the shapes in the brain.





Once the picture is in the head, drew a quick final rough largish sketch to work from.The beak is the most important piece, as it is the defining shape of the bird head (birds' heads are pretty much all the same shape, except for the beak)





 To create the beak, used some soft builder's mineral insulation. This is much the same as Oasis, the green stuff used in flower arranging 

Started by roughing out the block in outline form







With a carving knife (my trusty 12" ham slicer), sliced out the detail of the beak shape.






Once shaped, a bit of light sanding got rid of the visible cut marks from the knife blade







With final details carved and finished - ta da - one beak, shown against the rough sketch design. 

Head needs a controller

The remote control automata reading lamp head needs a suitably daft controller.
It uses a playstation 2 analog joystick as the input device,

but this needs something more anatomical to skin it with. It has been suggested a hand would be rather ironically appropriate. It should look like this, but match the MDF finish of the head

image from wpclipart.com

Arduino workshop

Have recently been in Atlanta at a great workshop run museum multimedia techies.
Here we hacked together 4 arduiono projects in about 3 hours

A prototype theramin. the tone rate changed, but didn't quite get the pitch to work

A light show controlled by changes in ambient light

Slide the glass game using proximity detectors

There was also a Flash animated fish in a Flash fishtank controlled by proximity detectors

3-d printing

This table is pretty nifty...













And is actually just printed out using a rather cool 3-d printer

Making high power (3W) LED eyeballs for the automaton

New eyeballs

The eyeballs in my automaton head work OK, but are woefully underpowered. Time to make some new ones!
This is looking at the basic starting point of a detachable eyeball from the front look towards the back. The hole is where the housing goes.

The housing is the (more or less) parabolic reflector from a torch

The eyeball is made detachable by adding a rubber grommet, which allows it to be pushed tight onto the servo control rod. The rubber friction holds it tightly in place.

The eyeballs are ready to attach, although not cosmetically finished yet.

Here they are hooked up to the breadboard to test how they work

They are remarkably more powerful. Each LED is 3W, which is pretty bright. It hurts t0 look straight into them

You can see how much more powerful the 3W led is on the left


Here the test is to see how much light they give off in total darkness. The head is meant to be a bedside/reading lamp with remote control directable beam, via the eyeballs.

Testing shows this is plenty of light!

Close-up it's easier to see how much light is given off.

Hacking VHS players for spare electronics parts

This is the inside of a dead VHS video recorder/player. It turns out it is still full of lots of old-school eletronics. Sure, there are lots of PCBs, but due to the mecahnical nature of video players with their big motors and stuff, there are a lot of useful connectors in there, as well as some high power resistors, transistors, loads of potentiometers and so on. A good way to pick up cheap parts.
Here is a handy 10 pin connector with the wiring all nicely connected. Try soldering anything remotely as neat as this, and you will see how useful a ready made is!

Here it is connected up to the breadboard jump leads coming off the arduino

And here it is fed into the underside of the head, from the board

Hacking PS2 controllers

Having got the basic arduino servo options sorted (if not finished), I have been rooting about for ready-made compact controllers. I have decided not to overstretch and will use a wired system for now, but may change to wireless later. Anyway, I wondered what's in a PS2 controller...

Here's what the PS2 controller looks like taken apart:

 

Here's what the joystick looks like. The blue things are potentiometers

The other side, showing the press down button (the white bar pushes down on the black switch

Here is the joystick wired up to the arduino controlling the servo












BLISS!

  

Some arduino code for servo control

THis is the latest version of lamp_head - the arduino test code for controlling my automaton lamp/head/thingy

a lot of this is redundant, but there are 2 functions
1. "readPots()" uses potentiometers to vary the voltage to analogue inputs, then converts this to a digital number then  uses that to control servo position. This would allow 2 controls (up/down and left/right)
2.  "manualUp() uses a switch to decide whether to incrementally increase the digital output . In this case, if the switch is on, then the output goes up, if it is off it sticks at the latest value. This could be used with a joystick, so that pushing up increases the UP/Down values incrementally, and pushing down would reduce it correspondingly. This would need four such inputs to be set up


circuit diagram

>>>>>>>>>>>>>>>>> here starts the sketch >>>>>>>>>>>>>>>>
/*
  Lamp head version 3 - this programme is to control the automaton lamp head
  Andrew Lewis September 2011
  This code is in the public domain.
  1. Turns on and off a light emitting diode(LED) connected to digital pin 13, when a switch attached to pin 2 is turned on.


 The circuit:
 * LED attached from pin 13 to ground
 * pushbutton attached to pin 2 from +5V
 * 10K resistor attached to pin 2 from ground
 

 */

// constants won't change. They're used here to
// set pin numbers:
// @@@@@@@@@@@@@@@@ stuff to do with LED controls
const int switchPin1 = 2;     // the number of the pushbutton pin
const int ledPin =  10;      // the number of the LED pin
int buttonState = 0;         // variable for reading the pushbutton status
int delay_val_LED=10 ;
// @@@@@@@@@@@@@@@@@@@

// @@@@@@@@@@@ This defines aspects fo the digital control
const int pinUp =11;  // constant to set the UP input to be digital pin 11 (d11)
// this
int delayer=10; // sets delay for digital control
int valUp=90;  //set manual number conrol UP at mid point by default =90

int upPin=11; //defines up eyeball control value pin to be digital pin 11
// @@@@@@@@@@@@@@@@@@@@@ end

#include // includes servo class file (out of the box from arduino.cc - TVM!)

Servo myservo;  // create servo object to control a servo
Servo myservo2; // create second servo object

int potPin1 = 0;  // analog pin used to connect the potentiometer (pot 1) for servo 1
int valPot1;    // variable to read the value from the analog pin for servo 1

int potPin2 = 1;  // analog pin used to connect the potentiometer for servo 2
int valPot2;    // variable to read the value from the analog pin for servo 2



int delay_val=15;  //the value of the servo wait delay fro both servos
int val_lamp=0; // lamp output value for fading up
// @@@@@@@@@@@@@@@@@@@@@@@@@@@@

void setup() {
  // initialize the LED pin as an output:
  pinMode(ledPin, OUTPUT); 
  pinMode(switchPin1, INPUT); // initialize the pushbutton pin as an input:
  pinMode(pinUp, INPUT); // sets digital PIN (defined by pinUp) to be the input for increases that make eyes go up UP
  // attach servos
  myservo.attach(5);  // attaches the servo on pin 9 to the servo object
 myservo2.attach(9); // attaches second servo to pin 8 to second servo object
}

void loop(){
  // lamp controls
  // fade_on();
   turn_on();
manualUp();  //Include this function to check for digital increases in UP value (this would be one of four needed to control eitehr a joystick or other four point controller
//readPots()// Include this function in the loop for dual analogue controls (1 potentiometer per servo)

   }
  
   // define manual increase meter
   void manualUp ()
   {
    
     if (digitalRead(pinUp)==LOW){
     valUp--;
    valUp = constrain (valUp,0,179);
 delay (delayer);
 }
     myservo.write(valUp);
   }
   ///define potentiometer function
  
  void readPots()
   {
      // read the state of the pushbutton value:

  // servo controls @@@@@@@@@@@@@@@@@@@@@
  // Servo 1 -------------
  valPot1 = analogRead(potPin1);            // reads the value of the potentiometer (value between 0 and 1023)
  valPot1 = map(valPot1, 180, 800, 0, 179);     // scale it to use it with the servo (value between 0 and 180)
  myservo.write(valPot1);                  // sets the servo position according to the scaled value
  delay(delay_val);    

  // ------------ servo 1 end
  // servo 2 ------------------------
  valPot2 = analogRead(potPin2);            // reads the value of the potentiometer (value between 0 and 1023)
  valPot2 = map(valPot2, 180, 800, 0, 179);     // scale it to use it with the servo (value between 0 and 180)
  myservo2.write(valPot2);               // sets the servo position according to the scaled value
  delay(delay_val);    
  // ------------ servo 2 end
  // end servo controls  @@@@@@@@@@@@@@@@@@@@@@ */
   }
void fade_on () {
 if ( digitalRead(switchPin1)==HIGH)  {val_lamp--;} //reduce if high
  else if (digitalRead(switchPin1)==LOW) {val_lamp++;}
  val_lamp = constrain (val_lamp,0,255);
  analogWrite (ledPin, val_lamp);
  delay(delay_val_LED);
}
void turn_on () {
 if ( digitalRead(switchPin1)==HIGH)  {val_lamp=255;} //reduce if high
  else if (digitalRead(switchPin1)==LOW) {val_lamp=0;}
  val_lamp = constrain (val_lamp,0,255);
  analogWrite (ledPin, val_lamp);
  delay(delay_val_LED);
}