THE USELESS MACHINE - COVID AVENGERS 2021

2020 was a tough year due to the Corona Covid-19. And it dramatically changes our lifestyle and human behaviors. We can't touch everything intuitively in public or before entering the shop; we subconsciously sanitize our hands, or we can shake hands with people we first meet or hug a friend we haven't see for a long time. Therefore, to commemorate this special year, this idea comes out.

Project by
Tzu-Ching Wen and Chien-Chun Kal Kuo

Parts

Here are all the components. Start from the hand, there are buttons on the palm as the trigger. And then the sprayer and the linkage mechanism on the former arm. On the upper arm, there is an actuator and the circuit. All of the customized parts are made by 3d printer, and tight by velcro on the arm.

Arduino Uno x1
Breadboard x1
Powersupply 24V x1
Adaptor 5V x1
Button Sensor x3
Servo Motor x3
Solenoid Valve x1
Relay x3
3D Printing Part

Mechanism

This linkage mechanism is driven by two servo motors, which are installed on both sides. Through exploded view, you can see the main transmission consists of three links, two connectors, one anchor, and one rotating output. This will perfectly demonstrate the slanted curve we need, which you can see the motion trajectory on the right. This idea is inspired by the land gear of the plane. By using the short link to drive the long link.

Trigger - Gestures

To activate this weapon. There are three buttons on your palm. Through three two gestures, it will come out with different features. These buttons are hidden under the fingerless glove and be installed on the 3d printing component.

Gesture A, which looks like a rocker, will trigger sprayer A, which is a soft and smooth spray.

Gesture B, which is the badass one. You clench your fist. The sanitizer will come out with high-pressure air to clean everything you are targeting without mercy. And vent all the anger from Covid-19.

Pneumatic

The spray system is driven by pneumatic. There are two metal cylinders. One is the high-pressure air CO2 cylinder. Another one is to contain sanitizer such as alcohol. Through 5 way 3 position solenoid power valves, the sanitizer will rush out to the designated port.

8mm PU pipes is been used for the connection. Besides, installing the regulating valve to adjusting the pressure for Sprayer A. And a Stop valve to control the CO2 cylinder.

Control System Logic

Two 5V relays are used to control the 24V solenoid valve to vent the pressurized air to the designated port through Arduino.

Arduino

In Arduino code, the variables are defined first at the beginning, including servo motors, led pin(for testing), relays and button sensors. Then in the Setup function, Button ports are all input, and the rest are output.

In the main function, there are two logics. One is for activating Sprayer A, another is for Sprayer B. One thing to note is the servo motor angle setting is opposite for each.

THE USELESS MACHINE - COVID AVENGERS 2021