Have you ever wanted to see how paper airplane are affected by their angle of launch? For my 9th grade physics class, I made a paper airplane launcher that could change angles! While I did not design the actual lego launcher, I did design the contraption that could change the angle of launch!
- A 2 ft x 4 ft piece of thin plywood.
- 6 Eye hooks.
- 6 Wood Screws (they should be pretty long, I recommend #6 x 1 in screws).
- 2 little hinges (with screws).
- 3 corner braces (with screws)
- Any type of twine that can go through the eye hooks.
- Big wooden corner brace (OPTIONAL, see step 7)
- Long 1" x 1" piece of wood (OPTIONAL, see step 7)
- An EV3 (Lego Mindstorms) set.
- A computer with the EV3 software installed.
- A protractor.
Step 1: Cut the Plywood
Cut the plywood into 4 sections of equal length (1 ft for each section) along the longest side of the wood.
On one of the 4 sections, cut 7 inches from one side of the wood.
You should be left with 5 pieces: 3 are big pieces, 1 is a medium piece, and 1 is a small piece.
Step 2: Attach the Hinges and Corner Braces
Take the medium piece and the small piece of wood (they should connect back together) and connect both pieces using 2 hinges. If the screws stick out the other side, trim them using the dremel (or some other tool) so they don't poke anyone.
Take 2 of the remaining large pieces and connect them together using 3 corner braces. Also, trim the screws if they stick out.
Step 3: Build, Modify, and Attach Mount for Lego Launcher
To build the launcher please go to the link and follow the instructions there (this was not made by me): INSTRUCTIONS FOR LAUNCHER.
To program the launcher, please go here and follow the video on the top (this was not made by me): VIDEO TO PROGRAM LAUNCHER
Next, there are a few modifications you have to make to allow the launcher to mount to the wood.
- Detach middle beam from bottom of launcher (first picture).
- Keep that for later.
- Take off rubber feet on the bottom of launcher (second picture).
- Take off top L-beam from each side of launcher (they are near the motors, 3rd picture will help).
- The L-beam part should be flush with the motor (4th picture).
- The pictures and annotations on the pictures can help explain what I mean in a little more detail.
ATTACH LAUNCHER MOUNT:
Lastly, mount that beam from the first modification on the medium sized piece of wood. You need to use the wood screws on the holes circled red in the 5th picture. Also add black lego connectors in the 3 spots circled blue in the 5th picture. For positioning of the mount, the 6th picture can help put the beam into perspective of the wood.
Step 4: Connect the Hinged Pieces to the Corner Braced Pieces
Use the two remaining corner brace screws (there should be 4 corner braces in the pack, which means there should be 2 screws left) to connect the small piece of wood (which is hinged to the medium one) to the pieces of wood which are corner braced. Use the pictures to guide you.
Step 5: Attach Eye Hooks and Twine
You need to attach the eye hooks in 3 different places.
The first place will be on the medium piece of wood which the launcher is mounted on. The eye hooks should be mounted on the corners that are the farthest away from the contraption (use the 1st picture as a guide).
The second place will be on the top of the vertical large wood piece. It will actually be going into the top of the plywood (see 2nd picture).
The last place will be also on the vertical large piece, but at the bottom. They will be in the back of the contraption and they will be at the bottom in the corner (see 3rd picture).
Lastly, lead the twine through the eye hooks in the back (at the bottom), up and through the eye hooks which are in the top of the plywood, then they should go all the way to the eye hooks by the lego launcher mount. Next, tie the twine around the eye hooks by the launcher. Then, cut the twine with about a foot and a half to spare at the end. See the embedded video to help with the twine positioning.
Step 6: Attach Screws to Act As Posts to Wind Twine Around
Next, attach 4 wood screws to the positions in the picture on the back of the vertical piece of wood. Make sure you only screw them until they barely push out the other side.
Step 7: Add Supports [OPTIONAL]
This step is optional, but recommended.
Use 3 screws to attach the big wooden corner brace to the side of the 90 degree angle between the already corner braced pieces of wood (see 1st, 2nd and 3rd pictures).
Also, use 3 screws to attach a 1" x 1" piece of wood down the middle of the vertical piece of wood (make sure it is on the back). See 4th and 5th pictures for clarification.
Step 8: Mount Lego Launcher and Fold Paper Airplane
Next, mount the lego launcher by connecting the top two black connectors on the lego launcher to the mount on the wood. Also, connect the Lego Mindstorms EV3 brick to the two motors.
Next, fold the paper airplane. YOU HAVE TO FOLLOW THIS DESIGN EXACTLY OR ELSE THE PLANE WILL NOT FLY!The design is in the 3rd picture (I did not make this design either).
Step 9: Use the Launcher!
To use the launcher, first use a protractor to hold the platform to the angle you want to launch at. Next, pull on the twine until it is taut and tie it around the screws sticking out on the back. Lastly, turn on the EV3 and run the program. Once you put the plane into the launcher, it should fly out pretty far. I also included a demo video in this step so you can see it working!