Shaky Stick with Pig Tail (Unbalanced Motor with MOSFET)

 

This project is basically a stick that shakes with a fake pig tail. I recently took apart my old talking stuffed animal toy called Piggy Says. It was an interactive game based on Simon Says. I wanted to reuse parts of it, such as the switch in its tail and the vibration motor that made it seem like it was laughing. The 3 AA battery compartment was from another toy I took apart, because the one from Piggy Says was corroded. The switch was designed to signal an integrated circuit which means it can't handle much current. That's why I added a MOSFET which can handle a higher current. I put a capacitor across the motor to protect the MOSFET from inductive spikes. I added a pull down resistor on the MOSFET to prevent it from turning half on which would cause it to get hot. 

The motor with unbalanced weight.

Resistor

MOSFET with heat sink (which wasn't really necessary)