Budget Tennis Ball Launcher for Full-Size Dogs

Battery and/or outlet-powered tennis ball launcher that larger dogs can drop balls into though a top funnel system. The speed of the motor is adjustable to allow the use of this device within indoor or outdoor settings. 3 different angle settings for the ball launch are included. Durable wooden structure yet competetive with the budget competition (ex. Amazon) which uses plastic. This device was made in part for my STEM concentration capstone project.

Parts

1. 2x4 1/2-inch plywood (x2, ~$30)
2. 10000 RPM 12V Motor (x1, $20)
3. Pololu 100mm Diameter Scooter Wheel (x1, $8)
4. Pololu Scooter Wheel to 5mm input shaft (x1, $5)
5. 7A Switch (x1, $13)
6. Standard-Size Alligator Clips (10-pack, ~$5)
7. 1/4-20 2-1/2" long threaded bolts (x2, ~$2)
8. 1/4-20 nuts (x2, ~$1)

Optional: 12V Battery

Total Part Cost: Around $84

Tools

• Drill
• Drill bits (specifically...)
• Jigsaw
• Tablesaw (recommended)
• Chopsaw (recommended)
• regular woodsaw (may be useful)
• 1-1/2in wood screws (x30, preferably countersunk)
• 1 in Phillips head wood screws (x6)
• 1/2 in Phillips head wood screws (x4)

All wood screws are in #8 size

This Manual is the key for symbols appearing on the construction drawings for fabrication.

I recommend cutting these 2x4 feet sheets of plywood down with a table saw due to their size.

For Openings with green surrounded by orange corners, drill the corners with a drill first and use that as an opening to insert a jigsaw to finish the rest.

If you wish to add a battery, add an extra support on the rightmost side of A-01 (in terms of the drawing).

You will need:

• Metric hex keys
• Phillips screwdriver

First, build the motor with all of its pieces and add it to the B-06/B-07 combined piece. Adjust the position of the piece and/or motor to make sure that the scooter wheel is in the middle of the slope intake (B-04). Mark the front location of the motor mount onto B-07. With only the motor mount, mark its pill-shaped openings onto

Make sure that the slope (L-02) has a wood thickness length between (in reference to drawing) its leftmost side and the left end of L-01.

Use sandpaper to get a good tolerance when trying to insert the motor controller into the rectangular opening.

Ensure not to add wood glue onto F-01, as it is meant to be removable for maintenance. On this note, try to use wooden screws that are either Phillips or slotted for ease of removal. If necessary, use clamps for wall pieces that may have warped over the course of production.

Depending on the battery, motor performance may be distinctly slower than with a wall outlet.

• Do not glue the front panel onto anything. It is meant to be easily removed with a screwdriver to access components such as the motor controller and its wires, switch the angle of the launch, and add a battery if necessary.
• To switch the launch angle, remove the bolt closest to the front, then just angle it to where the bolt can once again be inserted into the Angle Changer.
• The cavity where the ball exits from is meant to be fairly open (not just to adjust the launch angle), but it is also for removing junk that may happen to fall inside the device via the top funnel. Only do this when the motor is not in motion.
• You can use wood glue as a primitive Loctite by adding the glue into a hole before screwing in the wood screw. Only do this in locations that won't be removable (i.e., do not do this on anything connecting to F-01).

Do not...

1. Operate under rain, as it may damage the electronics and/or battery.
2. Operate for long periods of time, especially under severe heat temperatures.
3. Use any other ball type other than standard tennis balls, as it can damage the flywheel. If the ball is smaller than a standard tennis ball, the flywheel will not grab onto the ball and fail to launch.

Only input the device with 12-volt power.