You'll have a bit of control over what you choose for the motion sensor, motor, and jumper wires. You can pick up a pack of six SG90 motors from Amazon for a little under $12. A 10-pack of the HC ...

When the IR sensor senses a hand, it sends a message to the pump to turn on,” Navya shares. “When pressed, the pump is signalled to turn on, and it dispenses liquid.