In order to make the movement in the mechanical arms we used an Arduino microcontroller attached with 2 engines and a load cell to control the amount of toothpaste to put in the toothbrush.

This Arduino device is controlled by a relay, which is further connected to a power bank to provide 5V on it, and also a raspberry pi which is also attached to a 5V source. This last source is the power transformed from the power plug.

We plugged the raspberry pi in the power plug because e it is a fragile system that should receive constant clean power. We also should say that the relay we used is a switch that opens and close the main circuit composed by the Arduino and the engines and load cell.

It is also important to say that in the test phase while we were trying to complete this task we used a button in order to start the whole system. This means that this button should initiate the load cell and the first engine. After the enough amount of paste was weighed the system controlled by the Arduino should stop the first engine and the load cell and run the second engine which brings the toothbrush. Just after the load cell receives the message this engine should bring the toothbrush inside again and stop the circuit.