This is my LEGO Minifig Head Mk. 2

The original head was starting to get beat up pretty good, so I built a new one. As they are made out of solid Styrofoam, they get pretty warm, so I have a fan system to keep me cool. In the previous version, the fans were activated by a switch in my left LEGO hand and run by a battery pack in my pants pocket. While this worked, it was a chore to get in and out of, and I would usually require assistance getting the wires run and connected.

When I started building Mk. 2, I decided to try to eliminate that issue. I have taken an Arduino Uno and an Arduino Mega 2560 and connected them via two Nordic NRF24L01+ boards. The Uno has 3 switches and is run by a 9V battery. I am currently only using one, the other two are for future plans. When the pin connected to the fan switch goes high, it sends a code (the number 11 in this case) wirelessly to the receiving unit on the Mega. When the Mega receives that code, it closes a relay and starts the fans.

I used Maniacbug’s RF24 Library available on Github – https://github.com/maniacbug/RF24. I found the examples included with the library kind of hard to understand (I’m not a programmer), but I found this example – www.bajdi.com/rf24-library-revisited – and I got my project up and running.

The sketches I used (note, I had a lot of serial.print statements for debugging and I’ve commented most of those out):

For the sending unit:

#include <SPI.h>
#include “nRF24L01.h”
#include “RF24.h”
int msg[1];
RF24 radio(9,10); //define the CE and CSN Pins
const uint64_t pipe = 0xE8E8F0F0E1LL; //Send and receiving units addresses must match
int SW1 = 5;

void setup(void){
Serial.begin(9600);
radio.begin(); // set up the radio
radio.openWritingPipe(pipe);} // Open the radio for sending

void loop(void){
if (digitalRead(SW1) == HIGH){
msg[0] = 11; // Code that is sent to the receiving unit
radio.write(msg, 1); // send code if Pin defined above is HIGH
//  Serial.println(“Switch high”);}}

And for the receiving unit:

#include <SPI.h>
#include “nRF24L01.h”
#include “RF24.h”
int msg[1];
RF24 radio(48,53); //define the CE and CSN Pins
const uint64_t pipe = 0xE8E8F0F0E1LL; //Send and receiving units addresses must match
int relay = 7;

void setup(void){
Serial.begin(9600);
radio.begin();
radio.openReadingPipe(1,pipe);
radio.startListening(); // Open radio in receive mode and start listening
pinMode(relay, OUTPUT);} // Set relay pin to OUTPUT

void loop(void){
if (radio.available()){
// Serial.println(“Radio Available”);
bool done = false;
while (!done){
done = radio.read(msg, 1); // poll Radio
// Serial.println(msg[0]);
if (msg[0] == 11){ // if Radio receives ’11’ from sending unit, set relay pin high
delay(10);
digitalWrite(relay, HIGH);
// Serial.println(“Pin 22 High”);
}
else {
digitalWrite(relay, LOW);
// Serial.println(“Pin 22 Low”);
}
delay(10);}}
else{Serial.println(“No radio available”);}}

Here’s a short video of the system working:

The next plan is to wire a couple of other gadgets to the Mega and I have a relay board I will be using to control them.

If you’ve been following Midsouth Makers you know that we’ve been building. using and tweaking our 3D printers for a while now. Well thanks to a kind donation by LulzBot we now have a dedicated 3D printer at the space for member use! The printer is an AO-101, a MendelMax 1.5 variant.

The AO-101 currently uses 3mm filament and can print in ABS, PLA, Nylon and even Laywoo-D3 wooden filament.  We  have it setup to allow for remote printing on the LAN, using either OctoPrint or Repetier-Server. We recommend Repetier-Server due to it’s stability.

The AO-101 will be using a donated a 1U server as the host computer. Repetier-Server will allow you to load a gcode file and control the printer. We will be exploring webcam functionality for use in monitoring and in generating time-lapse print videos.

We will need the following items to get our new 3D printer setup and functional:

• Filament- Currently setup for 3mm:
  • ABS
  • PLA
• Webcam- Logitech C110 or C270 preferred (we’ve already tested and confirmed stability)
• 120mm silent PC case fan

AO-101 Specifications

• Build Area – 190mm 200mm 100mm
• Hot-end – Budaschnozzle 1.2
  • Extrusion temperature range – 180C – 240C
• Filament- Currently setup for 3mm and can reliably print the following material types:
  • ABS
  • PLA
  • Taulman 618 Nylon
  • Laywoo-D3 Wooden Filament
• Heated Print Bed (65C-110C)
• Borosilicate Glass Bed  with PET film on one side for printing with ABS and bare glass on the other side for printing with PLA
• Integrated Filament Mount for either loose coiled filament or spindles for spooled filament

Current AO-101 Modifications

• Nozzle Fan for printing in PLA installed but not hooked up
• RGB LED lighting (white for now)

More information on the new 3D printer can be found in our wiki.

If you’d like to use it, please contact Claudio, Ben, Dan or Cliff- more information will follow. In order to have access to the 3D printer without one of us present you will need to have had verified prior experience with a RepRap 3D printer, or attended an upcoming class on running & troubleshooting 3D printers(TBD) or be able to demonstrate the appropriate knowledge.

Please show our thanks and appreciation to LulzBot and the RepRap community!

We are slowly and painfully making progress with learning to fly our 3D Printed Mini Quadcopters. Cliff has helped us out with some tweaks & balances. Hopefully some more members will be interested in building their own, and will help add to the swarm.

Recently Ben, Cliff and Claudio have built Diametric’s Mini Quadcopter. We met a fellow RepRap user- Diametric- at this years Midwest RepRap Festival in Elkhart Indiana. He brought along a 3D printed quadcopter that he designed and built.

The quadcopters are remarkably inexpensive, the design, models and bill of materials can be found on Thingiverse. They are easy to build and easy to get off the ground. We’re still learning how to fly them however. While all three have taken flight, we have had some accidents and damaged the frames on 2 of them, twice. We’re not too worried when that happens, for we can always reprint the frame within about an hour and a half on one of our 3D printers.

Building the quadcopters

Claudio’s Quadcopter

Cliff’s Quadcopter

Claudio’s Second Quadcopter

Ben’s Second Quadcopter

Ben’s Quadcopter- We are still learning…

The HAM Radio Technician License is the entry level licensing for Ham Radio operators to get their call sign and the ability to talk over the air. On August 13th (after an abbreviated regular meeting) we’re going to hold our very own study group to prepare to take the Technician’s License test. We won’t be administering a test, but we will be covering where and when you can take the test and we’ll be covering topics covered on the test. If you’re interested in learning about HAM radio please join us at 7pm in the Nolan Building at Christian Brothers University. There is no cost involved. (Donations are welcome)