Introduction: Solar Powered Robot From TRASH!!!!

Update; My age category for the contest is 13-18 because I am fifteen. :)

Yes, the title explains it pretty well. In this Instructable I will show you step by step how to construct a light sensitive, solar powered, robot. All you need is some parts that can easily be found in the trash or in your backyard. I built mine totally from trash.

Step 1: Bits and Pieces


2- 1.5 volt motors
1- AAA battery pack that holds 2 batteries
1- On/Off switch
1- Old solar powered garden light
Random bits of wire
zip ties

And something to use as the chassis for your robot, I used some bits of Erector Set parts, but almost anything can be used.


Needle nose pliers
Wire stripper
Scissors or wire cutters
A vice grip (optional)
Magnifying glass (optional)
Soldering iron and solder (not optional)
Glue gun and glue

Step 2: And So It Begins...

For this step you will need...

Screw driver


Begin with the old solar light, you will have to open up the top and remove the solar panel and control circuit without damaging any of it. Follow the notes on the pictures to see how. Make sure to read all the notes as some wires need to be cut, while others do not.

Step 3: Assemble the Curcuit

In this step you will need...

Soldering Iron, solder, motors, switch, and the battery case.

When wiring the motors, don't worry about polarity (positive and negative), you can fix which way the motors spin by rewiring the motors later on. How the are wired dictates how they spin, and which way you want them to spin is going to depend on your frame you mount this on.

I guess while we are on the subject of the circuit I should explain how this works...

The circuit from the solar light is meant to charge a battery from the panel during the day, and discharge that battery through 2 LED's at night. By replacing the LED's with motors and putting in a more powerful battery pack, we do two things to this circuit;

1. The circuit will still charge the batteries, but only while the robot is on.

2. When the robot is in the dark it will run at half power, and full power in the sun. Meaning the motors will run slowly in the dark, and faster in light.

Step 4: The Frame

In this step you will need...

Something you can modify into a frame or an erector set like what I used.
Hot glue gun
zip ties

In this step you need to mount the circuit onto a frame. For my frame I used some random pieces from an erector set, but there are many things that can be used. The shape of my robot was inspired by robomaniac 's beetlebot v2 , which you can find here .

Follow the notes in the pictures to see how to mount onto a frame like mine. If you have one different than mine, you are on your own for this step.

Step 5: Testing and Rewireing

In the below video you can see the robot accelerates when a light is shone on it, but spins in a circle because one of the motors was reversed.

If this happens to your robot all you have to do is re-solder the motor wires in reverse. So the one that used to be negative is now positive.

Step 6: Video of Finished Project

In the below video you can see the finished robot running forward.

I hope you enjoyed this Instructable! Any comments or constructive criticism is very welcome!

National Robotics Week Robot Contest

Second Prize in the
National Robotics Week Robot Contest

3rd Epilog Challenge

Participated in the
3rd Epilog Challenge