Introduction: The Discreet Garden Defense System

This instructable was created in fulfillment of the project requirement of the Makecourse at the University of South Florida (www.makecourse.com)

This project is the Discrete Garden Defense System -- a laser turret that is attached to a servo head that moves back and forth and is fired via IR control. This guardian sweeps its head left and right, surveying the grounds to protect your garden. This project is also very adaptable and can be used on many different platforms, such as remote control vehicles and cat toys (my cats love it).

WARNING! Do not point laser at eyes!

Step 1: Components

  • Arduino Uno Micro-controller
  • IR Sensor
  • IR Remote
  • Standard Size Servo Motor (most sizes should fit in the turret base)
  • 4 AA alkaline batteries
  • Battery holder (got mine from RadioShack)
  • Transistor
  • 1K Ohm Resistors
  • Jumper wires
  • Small Breadboard
  • 5 mW 3 V Laser Diode
  • Soldering Kit
  • Dremel Kit with Basic Accessories
  • 3D Printing Capabilities
  • 7.62 x 4.62 x 2.25 inch Box (or of similar dimensions)
  • (optional) Fake or Real Moss

Step 2: 3D Model

Download the following AutoCAD files. These are stl files that can be taken to a 3D printer for assembly.

Step 3: Code

The Arduino Sketch below controls both the servo motor, IR remote, and laser diode. Make sure you have the appropriate libraries to run the code properly with. You can get them at makecourse.com in the course materials tab.

Step 4: Setting Up the Electronical Components

picture 1: This is the Fritzing Diagram of the control system. Follow the wiring step up and connect the IR sensor, servo motor, and laser together with the breadboard. The laser diode is represented by the red LED. The IR sensor is the little black box in the lower portion of the breadboard.

picture 2: Here is a physical demonstration of the set up in real life.

Step 5: Assembly

Following these step-by-step instructions for assembling your garden defender

1. Using the dremel cutting head, cut a small indent on one side of the box for the IR sensor and an even smaller hole on the lid where you plan to mount your turret base. You can also 3D print the box with these holes already in it. Whatever you do, make sure to smooth down the edges so to avoid damaging the wires and yourself.

2. Place the arduino board, breadboard, and battery holder in the box. I used poster sticky tacks to mount these so that I can easily remove them and they wont jostle around.

3. Set up the IR sensor as shown in the fritzing diagram and make sure it is facing the opening on the side of the box. In order to use the sensor with your desired infrared remote, you have to go into the Arduino code and open up the serial monitor. Just hit the buttons that you want to use for controlling the turret and change to variable definitions to match whatever series of digits are displayed for that button.

4. Mount your laser diode into the turret head. If you use the same lasers I did, you'll need to solder on some jumper wires so that they reach all the down to the breadboard. Just make sure you leave one side of the jumper wire intact. Here are the lasers I used; http://www.ebay.com/itm/20-PCS-3V-650nm-6mm-5mW-Mi...

5. Attach the turret head onto your servo's removable platform and feed the wires coming out the back through one of the small holes meant for the servo's mounting screws. You can use adhesive or small screws for this.

6. Mount the turret base onto the box lid so that the holes in each line up. I used superglue for this.

7. Place the servo with the turret head into the turret base, making sure there's some wiggle room for the wires to fit, as illustrated in the second image.

8. Connect the servo to the power source and its respective pin. Make sure it is hooked up directly to 5V on the UNO board instead of the breadboard power rail.

9. Connect the Laser diode to the breadboard power rail and transistor.

10. Check your connections, close up the box, and cover in desired foliage.

Step 6: Play With It