Glow-in-the-dark Space Rocks

Small (45mm) 3D printed Space Rocks, that glow in the dark.

First attempt at mould-making with silicone and casting in Jesmonite

A small test, mould-making from the lumpy Space Rocks created using Meshmixer, plus the resulting Jesmonite cast.

Arduino audio tests

Arduino audio tests using the Mozzi library, a Nano board, a light dependent resistor and a potentiometer (volume control).

http://sensorium.github.io/Mozzi/learn/introductory-tutorial/

 

Arduino networked lamp test

Working through this tutorial currently, trying to understand how Processing can be used to network an Arduino and power the colour of a lamp from words featured in an XML feed (in this case my blog feed – replacing the word ‘love’ with ‘space’ and the word ‘peace’ with ‘rock’). This generates the colour #3C4C2C.

Space, rock and Arduino
Rock, space and Arduino

And after adding this post to the feed…
Note the slight colour change.

This is the circuit I used, from this website. The LED is a 4 pin one, which can generate any combination of RGB colour as light:

https://mayorquinmachines.weebly.com/blog/arduino-project-arduino-networked-lamp
https://mayorquinmachines.weebly.com/blog/arduino-project-arduino-networked-lamp

And the two versions of it that I built:

Arduino networked lamp circuit v1
Arduino networked lamp circuit v1, with RGB LEDs
Arduino networked lamp circuit v2
Arduino networked lamp circuit v2, with one LED

Here is the code used in Processing:

//Arduino Code for the Arduino Networked Lamp - Processing

#define SENSOR 0
#define R_LED 9
#define G_LED 10
#define B_LED 11
#define BUTTON 12
int val =0; //variable to store the value coming from the sensor
int btn = LOW;
int old_btn = LOW;
int state = 0;
char buffer[7];
int pointer = 0;
byte inByte = 0;
byte r = 0;
byte g = 0;
byte b = 0;

void setup() {
  Serial.begin(9600); //open up serial port
  pinMode(BUTTON, INPUT);
}
  
void loop() {
  val = analogRead(SENSOR);
  Serial.println(val);
 
  if (Serial.available() >0) {
    //read incoming byte
    inByte = Serial.read();
    if (inByte == '#') {
      while (pointer < 6) {
        buffer[pointer] = Serial.read(); 
        pointer++;
      }
      //now need to decode 3 numbers of colors stored as hex numbers into 3 bytes
      r = hex2dec(buffer[1]) +hex2dec(buffer[0])*16;
      g = hex2dec(buffer[3]) +hex2dec(buffer[2])*16;
      b = hex2dec(buffer[5]) +hex2dec(buffer[4])*16;
      pointer = 0; //reset pointer
    }
  }
  btn = digitalRead(BUTTON);
  //check if there was a transition
  if ((btn == HIGH) && (old_btn == LOW)) {
    state = 1-state;
  }
  old_btn = btn; //val is now old,lets store it
  if (state == 1) {
    analogWrite(R_LED, r);
    analogWrite(G_LED, g);
    analogWrite(B_LED, b);
  }
  else {
    analogWrite(R_LED, 0);
    analogWrite(G_LED, 0);
    analogWrite(B_LED, 0);
  }
  delay(100);
}
int hex2dec(byte c) {
 if (c >= '0' && c<= '9') {
  return c- '0';
 } else if (c >='A' && c <= 'F') {
  return c - 'A' + 10;
 }
}

And the code in Arduino:


//Arduino Code for the Arduino Networked Lamp - Arduino

#define SENSOR 0
#define R_LED 9
#define G_LED 10
#define B_LED 11
#define BUTTON 12
int val =0; //variable to store the value coming from the sensor
int btn = LOW;
int old_btn = LOW;
int state = 0;
char buffer[7];
int pointer = 0;
byte inByte = 0;
byte r = 0;
byte g = 0;
byte b = 0;

void setup() {
  Serial.begin(9600); //open up serial port
  pinMode(BUTTON, INPUT);
}
  
void loop() {
  val = analogRead(SENSOR);
  Serial.println(val);
 
  if (Serial.available() >0) {
    //read incoming byte
    inByte = Serial.read();
    if (inByte == '#') {
      while (pointer < 6) {
        buffer[pointer] = Serial.read(); 
        pointer++;
      }
      //now need to decode 3 numbers of colors stored as hex numbers into 3 bytes
      r = hex2dec(buffer[1]) +hex2dec(buffer[0])*16;
      g = hex2dec(buffer[3]) +hex2dec(buffer[2])*16;
      b = hex2dec(buffer[5]) +hex2dec(buffer[4])*16;
      pointer = 0; //reset pointer
    }
  }
  btn = digitalRead(BUTTON);
  //check if there was a transition
  if ((btn == HIGH) && (old_btn == LOW)) {
    state = 1-state;
  }
  old_btn = btn; //val is now old,lets store it
  if (state == 1) {
    analogWrite(R_LED, r);
    analogWrite(G_LED, g);
    analogWrite(B_LED, b);
  }
  else {
    analogWrite(R_LED, 0);
    analogWrite(G_LED, 0);
    analogWrite(B_LED, 0);
  }
  delay(100);
}
int hex2dec(byte c) {
 if (c >= '0' && c<= '9') {
  return c- '0';
 } else if (c >='A' && c <= 'F') {
  return c - 'A' + 10;
 }
}

This didn’t work the first time I ran it, so I had to specify the Arduino port that Processing should use and then…

 

Arduino research 17/05/2018

Today I’ve been looking at how to build the various Arduino circuits for the Space Rocks, and at some examples of relevant projects.

I made some basic sensor experiments with a Light-dependent resistor, ultimately using this code from the Make: Getting Started with Arduino book.

// Example 06b: Blink LED at a rate specified by the
// value of the analogue input

# define LED 9 // the pin for the LED

int val = 0; // variable used to store the value
 // coming from the sensor

void setup() {
 // put your setup code here, to run once:

pinMode(LED, OUTPUT); // LED is as an output

// note Analogue pins are
 // automatically set as inputs
 }

void loop() {
 // put your main code here, to run repeatedly:

val = analogRead(0); // read the value from the sensor

analogWrite(LED, val/4); // turn the LED on at
 // the brightness set
 // by the sensor

delay(10); // stop the program for some time

}

And this circuit:

LDR - LED circuit diagram
LDR – LED circuit diagram
LDR - LED circuit
LDR – LED circuit

Also stumbled upon How to Build an Arduino synthesizer with Mozzi library

The Mozzi library looks super-useful for sound generation:

Currently your Arduino can only beep like a microwave oven. Mozzi brings your Arduino to life by allowing it to produce much more complex and interesting growls, sweeps and chorusing atmospherics. These sounds can be quickly and easily constructed from familiar synthesis units like oscillators, delays, filters and envelopes.

You can use Mozzi to generate algorithmic music for an installation or performance, or make interactive sonifications of sensors, on a small, modular and super cheap Arduino, without the need for additional shields, message passing or external synths.

Note to self to also check out the Mozzi examples gallery.