hi all ,
i am trying to make ultrasonic sensor based hand sanitizer using arduino with relay.very close to it but facing some problem with the timer.hope u guys can help me correct the code
Materials i am using :
-Arduino nano
-5v relay (input pin connected to pin8)
-PC USB connection for powering the ardunio
-ultrasonic sensor
-3-6v dc pump
My code :
int pump = 8;
const int trigPin = 3;
const int echoPin = 2;
float duration, distance;
void setup() {
pinMode(trigPin, OUTPUT);
pinMode(pump, OUTPUT);
digitalWrite(pump, HIGH);
pinMode(echoPin, INPUT);
Serial.begin(9600);
}
void loop() {
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
distance = (duration * .0343) / 2;
Serial.print("Distance: ");
Serial.println(distance);
delay(100);
if (distance < 30) { //use can increase the distance
digitalWrite(pump, HIGH);
delay(50);//You can increase the water timing
}
else {
digitalWrite(pump, LOW);
delay(100);
}
}
what the above code does : it turns on the relay and then turns it off , but when i bring hand second time , it stays on 
what i want to do : i want the relay to turn on for 1sec then off and then dont turn on until i bring my hand the second time
thanks a lot in advance 
P.S. - a similar thread on this forum with the same issue i am facing , but he is using IR sensor .
i am trying to make ultrasonic hand sanitizer
Ultraviolet may be a useful sanitiser, ultrasound less so.
TheMemberFormerlyKnownAsAWOL:
Ultraviolet may be a useful sanitiser, ultrasound less so.
I am trying to use it with pump
Hi,
your if and else do the same. One of the cases must be digitalWrite(pump, HIGH);
based on the configuration of your relay.
At the moment, both are set to digitalWrite(pump, LOW);
critycal_:
Hi,
your if and else do the same. One of the cases must be digitalWrite(pump, HIGH);
based on the configuration of your relay.
At the moment, both are set to digitalWrite(pump, LOW);
hi i have correct that , please help me with rest of function
Hi,
there is a very similar thread in this topic, where I already wrote a code for that.
You could use this and modify it to your needs. Look at this thread:
Auto Hand Sanitizer Dispenser - Code Help
critycal_:
Hi,
there is a very similar thread in this topic, where I already wrote a code for that.
You could use this and modify it to your needs. Look at this thread:
Auto Hand Sanitizer Dispenser - Code Help
hi.thanks for reply , i have seen the thread already .being complete noob i tried to modify using following code but after uploading the code relay is constantly on.its not getting trigger.
here is updated/modified code (not working) :
const int trigPin = 3;
const int echoPin = 2;
#define DCwater_pump 8
// defines pins
long duration;
int distance;
int pumpState = 0;
int lastPumpState = 0;
void setup()
{
pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
pinMode(echoPin, INPUT); // Sets the echoPin as an Input
pinMode(DCwater_pump, OUTPUT);
Serial.begin(9600); // For serial communication
}
void loop()
{
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
//Distance calculation
distance= duration*0.034/2;
// Printinng the distance on the Serial Monitor
Serial.print("Distance: ");
Serial.println(distance);
if (distance < 30)
{
pumpState = digitalRead(echoPin);
if (pumpState != lastPumpState) {
if (pumpState == HIGH) {
digitalWrite(DCwater_pump,HIGH);
Serial.println("DC Pump is ON Now!!");
delay(500);
digitalWrite(DCwater_pump, LOW);
Serial.println("DC Pump is OFF Now!!");
}
delay(50);
{
lastPumpState = pumpState;
}
}}}
Hi,
because you coded the pumpState to the echoPin, which is always set as high.
I will try to guide you, so you can code it yourself:
The trigger from the other code was an IR sensor, which has only two states:
High and low. So whenever this state was changed, the pump was allowed to run, once the trigger was high again.
Your sensor returns values, which are being processed into a distance, so a whole
lot of numbers. Not only high and low, which is equal to 1 and 0.
You need to think about how to implement this state change with your sensor in mind.
There are a lot of options how to do that.
Friend i tried to put
pumpState = digitalRead(Distance)
Instead of
pumpState = digitalRead(echoPin)
But it didn't work
i guess i need to make changes in the following part :
if (distance < 30)
{
pumpState = digitalRead(echoPin);
if (pumpState != lastPumpState) {
if (pumpState == HIGH) {
digitalWrite(DCwater_pump,HIGH);
Serial.println("DC Pump is ON Now!!");
delay(500);
digitalWrite(DCwater_pump, LOW);
Serial.println("DC Pump is OFF Now!!");
}
delay(50);
{
lastPumpState = pumpState;
}
critycal_:
Hi,
because you coded the pumpState to the echoPin, which is always set as high.
I will try to guide you, so you can code it yourself:
The trigger from the other code was an IR sensor, which has only two states:
High and low. So whenever this state was changed, the pump was allowed to run, once the trigger was high again.
Your sensor returns values, which are being processed into a distance, so a whole
lot of numbers. Not only high and low, which is equal to 1 and 0.
You need to think about how to implement this state change with your sensor in mind.
There are a lot of options how to do that.
or should i use distance instead of echoPin
if problem solved please help us
Hi,
Please find the code which I used with same setup to sanitizer dispenser.
/*
Vinod Amarathunga
WaterPump Ultrasonic Distance Based V 2.0
vinod.amarathunga@dmselectronics.com
*/
// defines pins numbers
const int trigPin = 9;
const int echoPin = 10;
// defines variables
long duration;
int distance;
//define priState
bool priState;
void setup() {
pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
pinMode(echoPin, INPUT); // Sets the echoPin as an Input
Serial.begin(9600); // Starts the serial communication
pinMode(6, OUTPUT); //Sets the Relay Digital Input
priState = false;
}
void loop() {
// Clears the trigPin
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
// Sets the trigPin on HIGH state for 10 micro seconds
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
// Reads the echoPin, returns the sound wave travel time in microseconds
duration = pulseIn(echoPin, HIGH);
// Calculating the distance
distance = duration * 0.034 / 2;
/*
// Prints the distance on the Serial Monitor
Serial.print("Distance: ");
Serial.println(distance);
*/
if (distance < 10 ) {
if (priState == false) {
Serial.println("Pump On");
digitalWrite (6, HIGH);
priState = true;
delay (500);
digitalWrite (6, LOW);
}
delay (5000);
}
else {
digitalWrite (5, LOW);
priState = false;
}
}
Video How it works: Quick Share
Valid until: Jun 19, 2020
Edit delay to dispense more
priState = true;
delay (500);
Items used: HC-SR04/ Arduino Nano/5V DC Relay/Small 7V DC Aquarium Peristaltic pump
digitalWrite (5, LOW);
What is attached to pin 5?
Sorry, It should be
else {
digitalWrite (6, LOW);
priState = false;
vinodamarathunga:
Sorry, It should be
else {
digitalWrite (6, LOW);
priState = false;
No, it should be digitalWrite (pumpPin, LOW);
D PIN 6 is the Relay Control Input na d I have not defined any pumpIN variable in my code.
vinodamarathunga:
Reason ?
It's a great habit to learn.
And it makes boo-boos likedigitalWrite (5, LOW); even easier to spot, fix or modify.