Corona-virus Riposte 1: Automatic Antiseptic Gel Press

The corona-virus is wreaking havoc in the world and it's sad, everyone is trying to find a solution to stop it, and the maker community is in the race too, they are helping by designing protective masks, respirators, robots etc...
With this in mind, we also get into the race and here is the first tuto that shows how to make an automatic antiseptic gel dispensing device, without the need to press the bottle because it is good that the virus is easily transmitted through objects so it is better to avoid touching them.

French version => https://bloctechno.wordpress.com/2020/03/23/corona-virus-riposte-1-presse-gel-antiseptique-automatique/

The Materials

- Imprimante 3D
- soldering iron

- wood (for support)

- arduino nano

- proximity ir sensor

- servomotor continuously rotating (360)

- 5V power supply or Power-bank

First Step 3D Design

We've already done the design for you, so you don't have to do anything on this side. As software we use FREECAD, if you want to modify the parts please find it here thingiverse or github in Freecad folder.

Second Stage 3D Printing

Download the 6 STL files that are on the thingiverse site and prepare the Gcode, here we have used CURA to do the SLICING, but there is other software (slic3r, repeater, etc), we advise you to separate the printing in two parts, the first one for the three files " the screw, the nut and the connecting tip "; the second one the three remaining " piston, cover, main block " with the following configurations:

first printout
FILAMENT TYPE: PLA

INFILL : 50 %

RESOLUTION (fineness of layers): 0.2

SUPPORT: not required

second printing

FILAMENT TYPE: PLA

INFILL : 15

RESOLUTION (fineness of layers): 0.4

SUPPORT: yes

Electronics

solder the connections as shown in the diagram
- Arduino nano

- proximity detector

- servo-motor with 360° continuous rotation

- 5v battery or power-bank

cut the wire of the servo-motor, pass it through the reserved hole and solder it to the arduino card, the same as for the sensor, take 3 wires, pass them through the hole and solder it to the card.

For the power supply you have the choice between using batteries or a power-bank, in our case we used a power-bank, we took a USB cable that we cut, then soldered the red wire to the +vcc of the arduino card and the black wire to the ground -.

Code Arduino

download the code and upload it to the arduino card.

In this tutorial we use a parallax continuous rotation actuator, they have a small potentiometer next to the connector output, this potentiometer allows to fix the rotation of the actuator in the middle. So when you upload the code; without touching the sensor, if you see that the servo motor continues to rotate, take a screwdriver, turn the potentiometer until it stops.

/* Descriptionn : this code is used to control a servomotor when the proximity sensor detects the hand VERSION : 1.0 DATE CREATION : 22/03/2020 LICENCE : AGPL v3 AUTHOR : Mamadou DIALLO EMAIL : diallo@bloctechno.com ABOUT : in this tutorial a parallax continuous rotation actuator is used, they have a small potentiometer next to the connector output, this potentiometer allows to fix the rotation of the actuator in the middle. So when you upload the code; without touching the sensor, if you see that the servo motor continues to rotate, take a screwdriver, turn the potentiometer until it stops. */ //include librairie #include //define pin for proximity sensor #define sensor 2 //create servo instance Servo servo; // setup code void setup() { // enable serial communication Serial.begin(9600); // setup pin for proximity sensor, here we use it on INPUT pinMode(sensor,INPUT); //setup servomotor pin servo.attach(3); } // loop code void loop() { // create variable and store value from proximity sensor int value = digitalRead(sensor); //for stop rotate of servomotor servo.write(90); //condition if the sensor detects the hand, the value of the variable is 0 LOW, // and the servo motor is commanded to rotate for 5s to lower the piston and after mount the piston during 4s if (value == LOW ) { servo.write(0); // lower piston delay(5000); servo.write(180); // mount piston delay(4000); } }

Downloads

code.ino

Assembly

Take the nut and put it in its place on the piston, in the rectangular notch and insert it inside as on the 3rd picture, then fix the main block on the wooden support, then put the piston inside the main block and put the threaded screw to hold the piston, then take the connecting end cap and fix it to the actuator, then put the head of the screw in the end cap and finally fix the actuator to the main block.

Finish

After finishing the assembly we glued the support on the wall with double-sided glue, then put our antiseptic gel, and finally plug in the power-bank, Yeah its working! 😀