We are the Purple Lego Eaters, a FIRST Lego League (FLL) team. This year's theme was Animal Allies, which means improving the relationships between humans and animals. Our problem is that there are raccoons going into garbage cans and making them sick. People are exterminating the raccoons, which costs lots of money. So we invented Uncle Victor's garbage guardian to solve the problem. It has 4 motion sensors on it to sense raccoons or other animals, and a radio and bright LEDs on it to scare away them away. In our research, we found that the raccoons are afraid of human voices, so we put a radio in that would tune into talk radio.

Link to the circuits.io simulation: https://circuits.io/circuits/3517782-uncle-victor-s-garbage-guardian-raccoon-scarring-away-machine

The reason why the one in the video does not look the same is because it was an earlier version of Uncle Victor's Garbage Guardian, and at that time we had to manually operate the lights. All of the photos are the most recent version.

Update #1: At our regional FLL tournament we qualified for the Razorback Invitational tournament at the University of Arkansas. We are currently looking for donations to help fund our trip. We created a go fund me page. All donations would be greatly appreciated. No donation is too small. The link for it is here:


Step 1: Materials


  • 5v LED and 220 ohm resistor (recommended for status indication)
  • Push button and 10K ohm resistor (used for testing)
  • Waterproofing equipment (if used outside)

Note: Depending on the battery and LED strips you are using, you might need a separate battery or power distribution board for the LED strips because of the voltage difference. You can also use a relay to turn the radio on and off if you want to use it with a different voltage.

The file attached states is a useful information sheet we found about the motion sensors that are listed here.

Step 2: Assembling the Radio

With your 5v radio, examine it and find out if you can solder wires to the power connectors without removing the case. Most likely you can't, and then you would remove the case. Then solder power terminals to the radio. I then recommend that you insulate the radio, so it doesn't short on anything. Solder pin headers to the wires that are soldered to the end of the radio. If you want to skip this step, you could cut a pin jumper in half and solder those wires to the radio.

Step 3: Pin Outputs

The pin outputs are as follows, with the Arduino Pin on the left:

Pin 12 – Radio Positive lead

Pin 11 – Relay switch

Pin 10 – Push button 2 (optional)

Pin 8 – Status LED (optional, but recommended)

Pin 7 – Signal pin on the 4th PIR motion sensor

Pin 5 – Signal pin on the 3rd PIR motion sensor

Pin 4 – Signal pin on the 2nd PIR motion sensor

Pin 3 – Signal pin on the 1st PIR motion sensor

Pin 2 – Push Button 1 (optional)

GND – Ground pin on all motion sensors, negative side of the radio, negative side of the relay power, negative side of all of the buttons

5V – All +power pins on all of the motion sensors, positive side of the relay power, positive side of all of the buttons

**In the circuits.io picture and schematic, the red LED represents the radio and the servo represents the PWM controlled relay we were using.

Step 4: Assembling the Code

The code should be attached to the instructables document, or you can get it from here:


It has the servo library installed for the relay we are using, however this can be changed depending on the type of relay or switch you are using. Check all of the pins in the program to make sure you have everything plugged in right. It basically works by waiting 20 seconds for the sensors to get initialize (it says it can take up to 60 in the manual for the PIR sensors I used, but if you find it annoying, then you can remove it), then flashing the status light and LED strips on, and then if any of the the buttons or motion sensors are pressed/triggered, it will set a variable to 1, and if all of them are not true then make the variable 0. Then if the variable is equal to 1, then it will turn the lights and radio on, and if it is 0 it will turn them off.

Step 5: Final Assembly

Next, you have to put all of the electronics into a container. We used a cheap plastic tupperware container that we made 4 holes in for the motion sensors, and made a hole for the led strps to go through. It is good to have extra containers, because it is hard making holes in the containers without completely sawing them in half. We destroyed 1 container before we got all of our holes right. Once the holes are drilled, we glued the motion sensors in place. Make sure you put glue on the plastic piece and the circuit board, because they will separate. Then feed the LED strips through the hole for them. Trim them to length, and unpeel the tape, and stick it to the sides of the container, going all the way around it. Remember, it is ok to have a little bit of overlap, because the more light there is, the more the racoons (should) be afraid of this. You will probably have to use another securing method to help them stay on. After that, put velcro on the sides and/or bottom for the battery to sit. Everyone's layout will be very different depending on what electronics you are using, so make sure you test fit everything before glueing or placing velcro. After that is all done, carefully transfer the wires to the container. Next, power it on and tune the radio to an all night talk radio channel. When you think you are done, do one final check to make sure that all of the wires are plugged in.

Happy Building!

<p>That's a good idea, and a great way to reuse materials :)</p>

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