DIY Automatic Alcohol Dispenser ($3 No Arduino Needed)

Summary

This week's project features a simple, motion-activated alcohol and soap dispenser. Using a DC water pump, aquarium tubing, a proximity sensor, a transistor, and a resistor, the device is designed to dispense liquid without contact. The tutorial demonstrates how to assemble the dispenser, including cutting tubing, wiring the components, and securing them with a hot glue gun. The project is powered by a USB cable and can be made portable with a power bank. It's an affordable, hands-free solution for dispensing alcohol to maintain hygiene.

Takeaways

• 🧪 Building a motion-activated alcohol and soap dispenser is the project's goal.
• 🌍 The project was inspired by kids using Dino's to build a hands-free dispenser.
• 💰 A low-cost version is being built without an Arduino, using affordable components.
• 🔌 Key components include a DC water pump, aquarium tubing, a proximity sensor module, a transistor, a resistor, wires, and a USB cable.
• 🏺 A recycled glass jar is used as the container, and labels are removed with acetone or hand wash alcohol.
• 🔩 The tubing is attached to the pump with a zip tie to prevent slipping.
• 🛠️ A hole is drilled for the wire and tubing, and the pump is prepared.
• 🔬 The circuit involves soldering a resistor, connecting the transistor to the sensor, and using a USB cable for power.
• 🔒 Hot glue is used to secure components and prevent short-circuiting.
• 💡 The dispenser can dispense viscous liquids like soap and is specifically designed for isopropyl alcohol.
• 🔌 Power can be supplied via a USB charger or a power bank for portability.
• 🛑 The proximity sensor has an adjustment knob to set the detection distance and limit liquid flow.

Q & A

What is the main purpose of the project described in the script?

The main purpose of the project is to build a simple motion-activated alcohol and soap dispenser without using an Arduino.

What is the cost of the DC water pump used in the project?

The DC water pump can be bought online for just less than $2.

What type of tubing is used for the project and where can it be sourced from?

Aquarium tubing is used, and in the script's case, medical tubes from a previous project were used.

What is the cost of the proximity sensor module mentioned in the script?

The proximity sensor module can be bought for a dollar.

What is the purpose of using a 1 kilo ohm resistor in the project?

The 1 kilo ohm resistor is used across the transistor's base to the proximity sensor's digital output in the circuit.

How is the container for the dispenser prepared in the project?

The container is prepared by recycling a glass jar that used to contain coffee, and the labels are removed using acetone or hand wash alcohol.

How is the tubing attached to the water pump to prevent it from slipping off?

The tubing is stretched and force-fitted to the water pump, and a zip tie is used to fasten it in place.

What is the purpose of using a hot glue gun in the project?

The hot glue gun is used to mount the proximity sensor and transistor in place, and to cover the circuit to prevent short-circuiting.

How is the power supplied to the project?

The project is powered from a USB power source, such as a USB charger or a power bank.

What is the function of the two LEDs on the proximity sensor?

One LED on the proximity sensor lights up to indicate power, and the other indicates when an object has been detected.

How can the flow of liquid be limited in the dispenser?

The flow of liquid can be limited by using the tip of a tried-out pen as a nozzle for the dispenser's outlet.