Making an automatic handsanitizer dispensor on a budget

In one of my engineering modules, I was tasked with a project with the aim to help the community. During this time, I have noticed that many handsanitizer dispensers that were used in public space were expensive and often bulky. I decided to make an automatic handsantizer dispensor that cost under R150.

Process of making the dispenser

The following components were used to make the dispenser:

• Arduino pro mini 5V
• 330 ohm resistor
• Custom 3d printed housing
• 2n222 transistor
• 5V pump
• Infrared distance sensor
• Nozzel
• USB connector

Putting the design together was quite simple, however, many challanges were encountered. One of them, were procurring the pump since the specific pump used was quite difficult to find. Secondly, the housing was to made small and reduce bulkiness.

I will upload the schematic at a later stage. Below is a video of the dispensor in operation:

The transistor and resistor were soldered directly on the arduino to save space:

Operation:

The transistor acts as a switch to control whether the pump is ON or OFF. When the transistors base pin is set to high, the pump turns on and when it is set to low, the pump turns off. Using this, the arduino code is written to mimic the behaviour seen in the above video.

Summary

The dispenser was successfully made at R142 which concluded the aim of the project. It is now planned to make an instruction kit so that children can build this dispenser, however, as well gain basic electronic and programming knowledge.