Automatic Kibble Dispenser
Kaéna TrenchantMarch 19, 2025
Description
Do you have a pet? Or do you want one? Everyone loves pets, for some it's more dogs, for others it's cats. However, owning a pet involves a number of responsibilities. Fortunately, most of us take very good care of them, but that doesn't mean we don't want to go away for the weekend and leave our cat alone for a day or two, for example. But nobody wants to leave their cat without food. So some people fill several bowls in the hope that the cats will manage the distribution of food correctly over 2 days. Unfortunately, this is rarely the case. I myself have 2 cats: Oslo and Misty, and I can assure you that they are particularly greedy. That's what prompted me to develop this adjustable automatic kibble dispenser, that may be controlled with your smartphone.
I invite you to follow my Instructable, so that you can reproduce this project, which is very close to my heart.
https://www.instructables.com/Automatic-Kibble-Dispenser/
This is the Arduino code, you'll need :
#include <WiFi.h>
#include <WebServer.h>
#include <HX711_ADC.h> //to install for the scale
#include <ESP_Mail_Client.h> //to install to send e-mail
#include <NTPClient.h> //to install to get the local time
#include <WiFiUdp.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define SMTP_server "smtp.gmail.com"
#define SMTP_Port 465
#define sender_email "[email protected]" //change with your informations
#define sender_password "****************" //change with your informations
#define Recipient_email "[email protected]" //change with your informations
#define Recipient_name ""
SMTPSession smtp;
const char *ssid = "your_ssid"; //change with your informations
const char *password = "your_wifi_password"; //change with your informations
WebServer server(80);
const int led = 2;
int weight;
int minweight = 15;
const int HX711_dout = 4;
const int HX711_sck = 5;
HX711_ADC LoadCell(HX711_dout, HX711_sck);
const int calVal_eepromAdress = 0;
unsigned long t = 0;
WiFiUDP ntpUDP;
NTPClient timeClient(ntpUDP, "europe.pool.ntp.org", 7200, 60000); //change 7200 according to your time zone --> e.g. if you're UTC+2, it will be 3600*2
char time1[6] = "6:30";
char time2[6] = "12:30";
char time3[6] = "18:30";
const int mot = 23;
void handleRoot()
{
String page = "<!DOCTYPE html>"; //we create a web page here to configure the distributor
page += "<html lang='fr'>";
page += "<head>";
page += " <title>Server ESP32</title>";
page += " <meta http-equiv='refresh' content='60' name='viewport' content='width=device-width, initial-scale=1' charset='UTF-8' />";
page += " <link rel='stylesheet' href='https://www.w3schools.com/w3css/4/w3.css'>";
page += "</head>";
page += "<body>";
page += " <div class='w3-card w3-blue w3-padding-small w3-jumbo w3-center'>";
page += " <p>Distributor configuration:</p>";
page += " </div>";
page += " <div class='w3-bar'>";
page += " <h4 style='text-align:left;font-size:70px;margin:20px;'>First distribution:</h4>";
page += " <h4 style='text-align:center;font-size:90px;'>"; page+= time1; +"</h4>";
page += " <a href='/time1sub' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%; float:left;'>-</a>";"";
page += " <a href='/time1add' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%; float:right;'>+</a>";"</br></div>";
page += " <div class='w3-bar'>";
page += " <h4 style='text-align:left;font-size:70px;margin:20px;'>Second distribution:</h4>";
page += " <h4 style='text-align:center;font-size:90px;'>"; page+= time2; +"</h4>";
page += " <a href='/time2sub' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%; float:left;'>-</a>";"";
page += " <a href='/time2add' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%; float:right;'>+</a>";"</br></div>";
page += " <div class='w3-bar'>";
page += " <h4 style='text-align:left;font-size:70px;margin:20px;'>Third distribution:</h4>";
page += " <h4 style='text-align:center;font-size:90px;'>"; page+= time3; +"</h4>";
page += " <a href='/time3sub' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%; float:left;'>-</a>";"";
page += " <a href='/time3add' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%; float:right;'>+</a>";"</br></div>";
page += " <div class='w3-bar'>";
page += " <h4 style='text-align:left;font-size:70px;margin:20px;'>Kibble mass per feed (in g):</h4>";
page += " <h4 style='text-align:center;font-size:80px;'>"; page+= String(minweight); +"</h4>";
page += " <a href='/minweightsub' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%; float:left;'>-</a>";"";
page += " <a href='/minweightadd' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%; float:right;'>+</a>";"</br></div>";
page += " <div class='w3-bar'>";
page += " <h4 style='text-align:left;font-size:70px;margin:20px;'>Ration supplémentaire :</h4>";
page += " <a href='/bonus' class='w3-bar-item w3-button w3-border w3-jumbo' style='width:30%; height:30%;margin-left:35%;;border-radius:50px;'>BONUS !</a>";"</br></div>";
page += "</body>";
page += "</html>";
server.setContentLength(page.length());
server.send(200, "text/html", page);
}
//Defined voids are used to modify variables such as distribution times and distributed mass
void time1addvoid()
{
int hours = atoi(strtok((char *)time1, ":"));
int minutes = atoi(strtok(NULL, ":"));
minutes += 5;
if (minutes >= 60) {
hours += minutes / 60;
minutes %= 60;
}
sprintf(time1, "%02d:%02d", hours, minutes);
Serial.println(time1);
server.sendHeader("Location","/");
server.send(303);
}
void time1subvoid()
{
int hours = atoi(strtok((char *)time1, ":"));
int minutes = atoi(strtok(NULL, ":"));
minutes -= 5;
if (minutes < 0) {
hours -= 1;
minutes = 55;
}
sprintf(time1, "%02d:%02d", hours, minutes);
Serial.println(time1);
server.sendHeader("Location","/");
server.send(303);
}
void time2addvoid()
{
int hours = atoi(strtok((char *)time2, ":"));
int minutes = atoi(strtok(NULL, ":"));
minutes += 5;
if (minutes >= 60) {
hours += minutes / 60;
minutes %= 60;
}
sprintf(time2, "%02d:%02d", hours, minutes);
Serial.println(time2);
server.sendHeader("Location","/");
server.send(303);
}
void time2subvoid()
{
int hours = atoi(strtok((char *)time2, ":"));
int minutes = atoi(strtok(NULL, ":"));
minutes -= 5;
if (minutes < 0) {
hours -= 1;
minutes = 55;
}
sprintf(time2, "%02d:%02d", hours, minutes);
Serial.println(time2);
server.sendHeader("Location","/");
server.send(303);
}
void time3addvoid()
{
int hours = atoi(strtok((char *)time3, ":"));
int minutes = atoi(strtok(NULL, ":"));
minutes += 5;
if (minutes >= 60) {
hours += minutes / 60;
minutes %= 60;
}
sprintf(time3, "%02d:%02d", hours, minutes);
Serial.println(time3);
server.sendHeader("Location","/");
server.send(303);
}
void time3subvoid()
{
int hours = atoi(strtok((char *)time3, ":"));
int minutes = atoi(strtok(NULL, ":"));
minutes -= 5;
if (minutes < 0) {
hours -= 1;
minutes = 55;
}
sprintf(time3, "%02d:%02d", hours, minutes);
Serial.println(time3);
server.sendHeader("Location","/");
server.send(303);
}
void minweightaddvoid()
{
minweight += 1;
server.sendHeader("Location","/");
server.send(303);
}
void minweightsubvoid()
{
minweight -= 1;
server.sendHeader("Location","/");
server.send(303);
}
/ / Sometimes our animal friends are well-behaved and we want to please them, so I've created a Bonus void that delivers a few extra kibbles immediately.
void bonusvoid()
{
digitalWrite(mot, HIGH);
delay(5000);
digitalWrite(mot, LOW);
server.sendHeader("Location","/");
server.send(303);
}
void handleNotFound()
{
server.send(404, "text/plain", "404: Not found");
}
//If there's an error, it will call this void
void errordistrib()
{
ESP_Mail_Session session;
session.server.host_name = SMTP_server ;
session.server.port = SMTP_Port;
session.login.email = sender_email;
session.login.password = sender_password;
session.login.user_domain = "";
SMTP_Message message;
message.sender.name = "Kibble dispenser - ALERTS";
message.sender.email = sender_email;
message.subject = "ERROR - DISTRIBUTION";
message.addRecipient(Recipient_name,Recipient_email);
String textMsg = "Unfortunately, the kibble dispenser doesn't seem to have worked!";
message.text.content = textMsg.c_str();
message.text.charSet = "us-ascii";
message.text.transfer_encoding = Content_Transfer_Encoding::enc_7bit;
if (!smtp.connect(&session))
return;
if (!MailClient.sendMail(&smtp, &message))
Serial.println("Error sending Email");
}
//void which measures the quantity of kibble
void weightmeasurement()
{
static boolean newDataReady = 0;
const int serialPrintInterval = 0;
// check for new data/start next conversion:
if (LoadCell.update()) newDataReady = true;
// get smoothed value from the dataset:
if (newDataReady) {
if (millis() > t + serialPrintInterval) {
weight = LoadCell.getData();
Serial.print("Load_cell output val: ");
Serial.println(weight);
newDataReady = 0;
t = millis();
}
}
Serial.println("Weight : " + char(weight));
}
void setup()
{
//Initialization of the motor
pinMode(mot, OUTPUT);
//Initialization serial monitor
Serial.begin(115200); delay(10);
Serial.println();
Serial.println("Starting...");
//Initalization LED
pinMode(led, OUTPUT);
digitalWrite(led, LOW);
//Connection attempt
WiFi.persistent(false);
WiFi.begin(ssid, password);
Serial.print("Tentative de connexion...");
while (WiFi.status() != WL_CONNECTED)
{
Serial.print(".");
delay(100);
}
Serial.println("\n");
Serial.println("Connexion etablie!");
Serial.print("Adresse IP: ");
Serial.println(WiFi.localIP());
//Define voids for each request
server.on("/", handleRoot);
server.on("/time1add", time1addvoid);
server.on("/time1sub", time1subvoid);
server.on("/time2add", time2addvoid);
server.on("/time2sub", time2subvoid);
server.on("/time3add", time3addvoid);
server.on("/time3sub", time3subvoid);
server.on("/minweightadd", minweightaddvoid);
server.on("/minweightsub", minweightsubvoid);
server.on("/bonus", bonusvoid);
server.onNotFound(handleNotFound);
server.begin();
Serial.println("Active web server!");
digitalWrite(led, HIGH);
//Starting the local time function
timeClient.begin();
//Sending of an e-mail to confirm successful start-up
ESP_Mail_Session session;
session.server.host_name = SMTP_server ;
session.server.port = SMTP_Port;
session.login.email = sender_email;
session.login.password = sender_password;
session.login.user_domain = "";
SMTP_Message message;
message.sender.name = "Kibble dispenser - INITALIZATION";
message.sender.email = sender_email;
message.subject = "ESP32 Testing Email";
message.addRecipient(Recipient_name,Recipient_email);
String textMsg = "The kibble dispenser has been switched on correctly.";
message.text.content = textMsg.c_str();
message.text.charSet = "us-ascii";
message.text.transfer_encoding = Content_Transfer_Encoding::enc_7bit;
if (!smtp.connect(&session))
return;
if (!MailClient.sendMail(&smtp, &message))
Serial.println("Error sending Email");
}
void loop()
{
server.handleClient();
timeClient.update();
String currenttime = timeClient.getFormattedTime();
currenttime = currenttime.substring(0, 5);
if(currenttime == String(time1) || currenttime == String(time2) || currenttime == String(time3)){
float chrono = 0;
LoadCell.begin();
float calibrationValue;
calibrationValue = -1040.0;
unsigned long stabilizingtime = 2000;
boolean _tare = true;
LoadCell.start(stabilizingtime, _tare);
if (LoadCell.getTareTimeoutFlag()) {
Serial.println("Timeout, check MCU>HX711 wiring and pin designations");
while (1);
}
else {
LoadCell.setCalFactor(calibrationValue); // set calibration value (float)
Serial.println("Startup is complete");
}
while(weight <= minweight){
digitalWrite(mot, HIGH);
delay(500);
chrono += 0.5;
weightmeasurement();
if(chrono>=20){
erreurdistrib();
break;
}
}
digitalWrite(mot, LOW);
delay(60000);
}
}
