Introduction: Wooden Catapult_Arduino

This is my school project, I think this mechanism can be improved a lot, and I have to spend more time on it to make it better.

Youtube video link:


Step 1: Supplies



  • Square ruler
  • Regular ruler
  • Line drawer
  • Chisel (12mm and 6mm)
  • Cabinet plane
  • Hammer


  • Pine wood pieces (about 7mm)
  • Arduino Leonardo
  • Servo motors (blue) x3
  • Switch
  • Computer
  • Rubber bands
  • Marble 13mm
  • Screw 2mm
  • Circuit board(mini)

Step 2: Setup

Required tools

  • Cabinet plane
  • Line drawer

Flatten the wood:

All sides and area have to be flattened by cabinet plane


Make sure the sides are flatted with right angle

The edge of the annual ring side might crack

Draw lines:

Use the line drawer to draw straight lines (like the picture shown)

Draw 3mm line away from the annual ring side line

Draw 440mm line away from the side line

Step 3: Cut

Use a hand saw to cut

  • 150mm x 70mm
  • 160mm x 44mm
  • 84mm x 44mm
  • pic 2 20mm x 30mm ten crave into that shape

Use a Chisel 6mm

  • make a 6mm x 6mm square hole at the middle of the annual ring side line and 10mm away from that line (pic3)
  • make the side that will contact with

Use a plane

  • make 160mm x 44mm and 84mm x 44mm piece annual ring side into 45 degrees (pic4, 5)

Step 4: Combine

Use wood glue to combine the woods together

Combine the thing in pic(1, 2) with the thing in pic(6) by an axle pic(4)

The brown wood cup pic(1, 2) is made by CNC

Cup 3D design (rhino):

Step 5: Combine With Arduino

Combine the wood piece in pic(3) with servo motor by a 2mm screw pic(1)

Combine pic(7) with servo motor to become pic(5)

Combine pic(4) with servo motor

Place Arduino Leonardo on the 150mm x 70mm wood piece

Step 6: Circuit


  1. Press/On
  2. D-pin(7)
Servo motor

  1. Pull rubber band D-pin(6)
  2. Lock D-pin(9)
  3. Push ball D-pin(10)

Step 7: Finish!

combine the rubber band on the servo motor (previous page pic 4) with (previous previous page pic 1,2)

Place marble diameter 13mm inside the machine on (previous page pic 6)


Woodworking Contest

Participated in the
Woodworking Contest