There are so many tasks I could have picked from for this, I chose to rekindle my 3D printing skills as it has been a while and got to printing the holding mechanism. I had the 3D models ready from the above design and so all I needed was a little time to print them (little being a complete lie, it took hours!).



I printed the parts from in the order shown in the picture from left to right. This took two days of printing at the lab plus a few hours of surface finishing. I chose a layer height of 0.1 mm for the parts.



The joints I made to fit the parts together went together pretty well after a bit of sanding and filing. One big issue I had was that the support structure for the board housing was extremely dense and required a lot of work to remove. But after that it was all good and the 9V battery fitted!







The next step is to produce the board that is designed to fit in the mechanism. I have already made a design for this but I doubt it will be the final design. Either way it will be good to have a "practise board to fit inside.

Check out the designs here

Preparing the design file for this was a little time consuming. It required quite a lot of work to get rid of double lines and uncecesary lines.



Before I went and cut this, I needed to get the exact values I wanted to use for cutting and engraving. So I gto some nice 3mm plywood and started testing.



for cutting the material, I found that a speed of 1.6 and power of 100 was best then for the test I used a speed of 90 and a power of 100.

For the first cut I forgot to flip the vectors so that the text wasn't mirrored so I did one more and have two cores. After a bit of filing I got the 3D printed part to fit.

Emma, our instructor had delivered a sample of PolyMax PLA filament for our 3D printer. Compared to the filament we normally use, PolyPlus PLA, this has 9 times the impact resistance. I had to try it out!

I noted in my last batch of 3D printing that it would be better to use a boolean union to join two of the parts together and print them as one:



Doing this would save time and improve the quality of the parts printed.

Before I started, Emma and I levelled the bed. This ended up being a rather time consuming task. At first we used a level to try and level the bed but this didnt prove accurate enough:



In the end we followed the tutorial provided by ultimaker and got a better (but not perfect!) result.

I set the printer to work. I reduced the fill density from 80% to 50% this time because the filament is so much stronger. In about 4 hours it was finished!





Like with the other parts, a bit of filing was required before fitting:



I prefer this filament not onyl because it is stronger but also it has a nice bit of flex to it.

For my first bit of code I opened up the Arduino example "Blink". I changed it accordingly and discovered that one pair of LEDs were faulty so I adapted it like so:

void setup() {
 // First pair of LEDS
    pinMode(9, OUTPUT);
   pinMode(8, OUTPUT);
 // Second pair of LEDS
    pinMode(5, OUTPUT);
   pinMode(3, OUTPUT);
}


void loop() {

  digitalWrite(9, LOW); 
  digitalWrite(3, LOW);
 
  digitalWrite(8, HIGH);
  digitalWrite(5, HIGH);
  
  delay(100);             
   digitalWrite(9, HIGH); 
  digitalWrite(3, HIGH);
  
  digitalWrite(8, LOW);
  digitalWrite(5, LOW);
  
  delay(300);    
}

My first set of traces let my control 6 LEDS using 6 pins. My redesign will enable me to do the same with three pins using charlieplexing:



I came up with these traces in Rhino. However, I want to refine the design more before cutting them:



Now I need to fix the design of my board and work on some code!

Now it was time to cut my new layout of traces (but not my last design of them!). This time I used a force of 90 instead of 80 (it turns out I needed to replace the knife). After a bit of weeding they were on:



With the help of Zaerc, our electroncs guru, I had the following code written up which changes the blink speed of the lights depending on the value given from the phototranssitor:

TODO MAKE VIDEO OF THIS

I now know that my hardware and software funstions. I now need to do a final design of the traces, work out how to secure the connecting pins, redesign the board housing and redesign the laser cut.

First thing I did was to begin printing the lower board housing. Then while that is printing I can mill the board, solder, and catch up on documentation. Here is the board all finished:



Not long after, the 3D print was also finished:



I then sent the upper half of the board housing for printing and used the time to laser cut, vynil cut and solder:



I used the same procedure to cut the traces and to laser cut the wood. The only addition is the female pins which the board will connect to. I soldered them then used a glue gun to hold them firm.



Seeing as my latest hardware was ready for testing, I thought I would get straight to it. You can see it all happen below:



By this time the three parts I needed to 3D print were ready so I fitted them to the Spatbord:







One minor design flaw is that the resistors need to be moved further down as the rest under the board housing. This is a quick fix with the traces design:

After leaving the epoxy to set, I took it out of the ventilation cabinet to see the result:



The expoxy added a few nice things to the item. It darkened the wood slightly and made it stiffer. The only downside was that the curve in the wood was pretty much gone. It was going to need more coats to improve the surface.

I then went to check on the other board that I left to dry after soaking and clamping it. This time the curve was a bit steeper:



I gave it the usual make over with the traces and components and it wa sready to also be coated in epoxy. First though I needed to do some 3D printing. I printed two more lower board housings and changed the filaments during the jobs to add some more colour:





The first one ened up breaking so it won't be used. The quality of the prints werent as good as the first one. I have put this down to the fact that I was using a different machine with different filaments.

Once the curing was complete I could assemble a working prototype and test it. I went ahead and did so. I also added some code which would turn off the lights all together when the surroundings get above a certain brightness. Here is the latest code:

#include  <SoftwareSerial.h>  
#define RxD 9
#define TxD 10

#define DEBUG_ENABLED  1
boolean state = false;
SoftwareSerial blueToothSerial(RxD,TxD);
unsigned long next1;
unsigned long next2;

void setup() {
    pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, INPUT);
  
  pinMode(RxD, INPUT);
  pinMode(TxD, OUTPUT);
  setupBlueToothConnection();
  next1=millis()+0;
  next2=millis()+500;
}
 void setupBlueToothConnection()
{
  blueToothSerial.begin(9600); //Set BluetoothBee BaudRate to default baud rate 38400
  blueToothSerial.print("\r\n+STWMOD=0\r\n"); //set the bluetooth work in slave mode
  blueToothSerial.print("\r\n+STNA=HC-05\r\n"); //set the bluetooth name as "HC-05"
  blueToothSerial.print("\r\n+STOAUT=1\r\n"); // Permit Paired device to connect me
  blueToothSerial.print("\r\n+STAUTO=0\r\n"); // Auto-connection should be forbidden here
  
  delay(2000); // This delay is required.
  //blueToothSerial.print("\r\n+INQ=1\r\n"); //make the slave bluetooth inquirable 
  blueToothSerial.print("bluetooth connected!\n");
  
  delay(2000); // This delay is required.
  blueToothSerial.flush();
}
//unsigned long next;
 int sensorValue;
void loop()
{
  sensorValue = analogRead(7);
  blueToothSerial.println(sensorValue);
  next1 = millis()+100;
if(sensorValue < 200)
{
  digitalWrite(6, LOW);
      digitalWrite(5, LOW);
      digitalWrite(4, LOW);
}
else{

  if(millis() > next1)
  {
     sensorValue = analogRead(7);
     blueToothSerial.println(sensorValue);
     next1 = millis()+100;
  }

  if(millis() > next2)
  {
    if(state)
    {
      digitalWrite(6, LOW);
      digitalWrite(5, HIGH);
      digitalWrite(4, HIGH);
    }
    else
    { 
     digitalWrite(6, HIGH);
     digitalWrite(5, HIGH);
     digitalWrite(4, LOW);
    }
    state = ! state;
    next2 = millis()+sensorValue;
  }
}
}   

import processing.serial.*;

Serial myPort;        // The serial port
int xPos = 1;         // horizontal position of the graph 

//Variables to draw a continuous line.
int lastxPos=1;
int lastheight=0;

void setup () {
  // set the window size:
  size(1280, 780);        

  // List all the available serial ports
  println(Serial.list());
  // Check the listed serial ports in your machine
  // and use the correct index number in Serial.list()[].

myPort = new Serial(this, "/dev/tty.HC-05-DevB", 38400); 

  // A serialEvent() is generated when a newline character is received :
  myPort.bufferUntil('\n');
  background(0);      // set inital background:
}
void draw () {
  // everything happens in the serialEvent()
}

void serialEvent (Serial myPort) {

  // get the ASCII string:
  String inString = myPort.readStringUntil('\n');
  if (inString != null) {
    inString = trim(inString);                // trim off whitespaces.
    float inByte = float(inString);           // convert to a number.
    inByte = map(inByte, 0, 1023, 0, height); //map to the screen height.
  // Sets 'a' to 27
    //Drawing a line from Last inByte to the new one.
 

    stroke(255,255,255);     //stroke color
    strokeWeight(3);        //stroke wider
    line(lastxPos, lastheight, xPos, height - inByte); 
    lastxPos= xPos;
    lastheight= int(height-inByte);

    // at the edge of the window, go back to the beginning:
    if (xPos >= width) {
      xPos = 0;
      lastxPos= 0;
      background(0);  //Clear the screen.
    } 
    else {
      // increment the horizontal position:
      xPos++;
    }
  }
}