We absolutely LOVE the new LEGO Star Wars sets that have come out over the last couple of years. They're well designed, fun to build, and look great. What would make them even more fun is if they also moved on their own!
We took an off the shelf LEGO BB-8 set and automated it so the head spins around! Even better, we added sound effects and lighting effects! But if that isn't enough we also added a motion sensor so that it would activate when someone walks by. Overall this project isn't overly difficult to do, but does take awhile and requires a healthy amount of random Technic LEGO parts to built the gear box area.
For LEGO parts we used such websites as BrickOwl.com or BrickLink.com. These sites are really handy to use for random LEGO parts or supplies. When in doubt you can also just buy bulk LEGO parts off eBay and spend the afternoon organizing them all.
LEGO BB-8 Set
Worm Gear Drive Set
Large Technic Gear
Technic 1x4 Brick x 4 (or 8)
Technic 1x8 Brick x 4
2x8 Plates x 4
Electronics:
We made up a Step by Step video to show off what the BB-8 can do and how to make it.
Using 1x4 and 1x8 Technic bricks, construct an adaptor to mount the BB-8 onto your large Base Plate.
Remove all the extra parts on the bottom of your BB-8. You want to leave the bottom white area completely flat.
Connect your white bricks UPSIDE DOWN to your black technic bricks.
We ended up using two of the 1x4 bricks per adaptor for extra strength, but it's probably not necessary.
We're using a 9G sized Continuous Rotation Servo with metal gearing, connected to LEGO using our Crazy Circuits adaptors. (Laser cut and open source!)
Attach the laser cut Crazy Circuits adaptors to the 9G sized servo.
Connect the round Servo Horn (laser cut disc) to the Servo. Using a couple of technic pieces and a gear, build out an adaptor on the end.
This allows your servo to directly interface with the axle on the worm drive.
We connected two 1x8 Technic bricks together and then attached the servo to those pieces.
Below them is a single 2x8 brick.
The main concern here is to keep everything secured and tightly together. The servo moves around a lot and the last thing you want is for your pieces to start popping off the large base plate.
We went all fancy and included an Ultrasonic Motion Sensor. To make it look nice we build a small LEGO based holder for it to hang out in. We can't take credit for this design, we randomly found it in a google image search.
Start with a 2x8 plate, attach some 1x2 bricks onto the side, two L shaped plates on the top edge, and a 1x8 across the top. Use a couple of 1x1 plated on the bottom (blue in our design).
We grabbed our sound clip via a YouTube Video. You can use any sound file as long as it's a .WAV or .MP3. (We can't give you a sound clip for Copyright reasons.)
You'll want to use just one sound clip for our code. Once you find one put it on a micro SD card formatted in FAT.
Put the Micro SD Card into the MP3 Player.
Make sure you take note as to how long your clip is, as it will be quite helpful when modifying the code.
BB-8 sounds are great as well as some classic Star Wars music.
If you've never used our Robotics Board before you'll need to read the user guide and install the right software and drivers.
You'll also need to grab and install the NewPing library as well.
Open up your Arduino software and copy our code into a new project window.
Lines 30 & 31 control how long the Servo will move when opening and closing the wings. We find that 20000 ms is about right. You can change the time by changing those values.
Line 91 controls how long the Servo pauses to wait for your audio clip. Since we want the head to spin constantly we just made this a big fat zero.
At this point it doesn't hurt to just test everything out to make sure things are working properly.
Attach some headphone or some small speakers to the MP3 player. If you have small desktop (computer) speakers that are wall powered, use them. They work best with this module.
Plug your system into a USB power source (computer or wall) and see if everything works. Wave your hand in front of the distance sensor to start everything off.
Push your LED holder (2x2 Round Plate) into place.
Trim your lines of tape and attach them to the studs.
Connect your LED. (If it doesn't turn on, rotate it. You probably have it put on backwards compared to you battery holder.)
Rebuild the head. Attach it to the body.
To easily turn your LED On and Off, just remove it.
When putting the head back on go very slowly. The connecting axle will push up through the head and disconnect your battery. Stop pushing when you feel a slight resistance.
Your BB-8 is now complete! Maybe this IS the droid you're looking for!
Apply this build to other LEGO projects. We more or less did the same build with our X-Wing and Clone ARC Fighter.
If you like our Crazy Circuits system check out all our other parts and projects at BrownDogGadgets.com!