第1步：項目

垃圾桶設(shè)計為在超聲波距離傳感器檢測到人員時打開。當(dāng)傳感器沒有檢測到任何人3秒鐘時，它會向后運行電機直到它按下按鈕。溫度和濕度傳感器（DHT）在垃圾桶中記錄條件并計算內(nèi)容物何時會腐爛。液晶顯示屏顯示時間，直到清空為止。

步驟2：零件清單

1 - Arduino MEGA 2560

1 - 面包板

1 - 10k歐姆電位器

1 - LCD屏幕（與Hitachi HD44780驅(qū)動程序兼容）

1 - DHT11

3 - 10k歐姆電阻

1 - 220歐姆電阻

1 - 電機控制L298N帶H橋

1 - 12伏直流電機

1 - 12伏電源

1 - 超聲波傳感器HC-SR04

1 - 按鈕

步驟3：機械設(shè)置

為了打開垃圾桶，我們制作了一個機械臂。它有兩個接頭，連接到電機和垃圾桶的蓋子。就像在第一張照片中一樣。

在秒圖中可以看到它安裝在電機上。

對于電機，我們鉆了一些孔并使用了拉鏈?？梢钥吹皆诘谌龔堈掌邪惭b在垃圾箱內(nèi)。手臂粘在蓋子頂部

對于超聲波測距儀，我們在垃圾桶前面鉆了2個孔，直徑= 16mm，間距為1厘米（見4和5圖片）。/p》

對于其他部件，我們剛剛為拉鏈或螺釘鉆孔。在為其鉆孔之后，LCD用螺栓和結(jié)安裝在蓋子上。帶拉鏈的arduino和馬達驅(qū)動器。

臂部件采用3D打印。原理圖是在Autofusion 360中制作的，并使用了以下文件：

第4步：Fritzing

第一張圖顯示了如何系統(tǒng)已連線。

步驟5：代碼

代碼分為五個不同的功能，每個功能控制一個不同的傳感器或一個傳感器的一部分。為了利用代碼，必須為每個函數(shù)創(chuàng)建一個“新選項卡”。

arduino項目文件夾必須包含每個函數(shù)的代碼作為文件。

為了程序運行不間斷我們使用millis（）和micros（）而不是delay（）。

該程序還需要以下庫，這些庫都可以在庫管理器中找到：

LiquidCrystal v1.0.7（內(nèi)置）

Adafruit Unified Sensor 1.0.2

DHT傳感器庫v1.3.0

主程序：

//Global variables are defined here. They‘re read through out the entire program.

//Local variables are defined within each function. They can only be changed or read within the function.

//Records whether the ultrasonic sensor has detected something.

//It’s controlled within the DistanceSensor function. It will stay on for four seconds when something is within range.

//Everytime it registers something it refreshes the timer.

boolean Distance_Close;

//Remembers if trashcan is open or closed. One is open and zero is closed.

bool TrashcanState;

//Monitors for local variables.

int ButtonMonitor;

int DistanceMonitor;

int CloseMonitor;

unsigned long TimeOpenMonitor;

unsigned long TimeUsedMonitor;

int DetectedMonitor;

int TemperatureMonitor;

int HumidityMonitor;

//Sets the pin numbers.

const int DCmotorIn1 = 5;

const int DCmotorIn2 = 6;

const int TrigPin = 8;

const int EchoPin = 7;

const int ButtonPin = 9;

const int rs = 13， en = 12， d4 = 11， d5 = 10， d6 = 22， d7 = 24; //Pin numbers for the LCD.

//Libraries， make sure to install all of them.

//All libraries can be found inside the Library Manager.

//“Adafruit Unified Sensor Library” must also be installed in order for dht to work even though it is not loaded.

#include

#include “DHT.h”

#define DHTPIN 3 //Defines which pin should be used for the temperature and humidity sensor

#define DHTTYPE DHT11 //Defines which type of DHT is used. If you have a DHT22 replace DHT11 with DHT22.

DHT dht（DHTPIN， DHTTYPE）; //Loads the defined pin and type.

LiquidCrystal lcd（rs， en， d4， d5， d6， d7）; //Tells the program which pins are installed.

void setup（） {

// Code that needs to be run once：

Serial.begin（9600）; //Starts communication with the monitor. Make sure that the monitor have the same BAUD speed.

//Determine if pins are reading or writing.

pinMode（TrigPin，OUTPUT）;

pinMode（EchoPin，INPUT）;

pinMode（DCmotorIn1， OUTPUT）;

pinMode（DCmotorIn2， OUTPUT）;

pinMode（ButtonPin，INPUT）;

dht.begin（）;

lcd.begin（16， 2）; //Sets the dimension of the LCD

}

void loop（） {

// put your main code here， to run repeatedly：

DistanceSensor（）; //Constantly checks if someone is near the trashcan

OpenTrashcan（）; //Checks if the trashcan should opened.

CloseTrashcan（）; //Checks if the trashcan should be closed.

LCD（）;

TempHumid（）;

//Creates a table for monitoring all the different variables.

Serial.print（“Trashcan State ： ”）;

Serial.print（TrashcanState）;

Serial.print（“ ”）;

Serial.print（“Distance_Close： ” ）;

Serial.print（Distance_Close）;

Serial.print（“ ”）;

Serial.print（“Button： ” ）;

Serial.print（ButtonMonitor）;

Serial.print（“ ”）;

Serial.print（“Temperature： ” ）;

Serial.print（TemperatureMonitor）;

Serial.print（“ ”）;

Serial.print（“Humidity： ” ）;

Serial.print（HumidityMonitor）;

Serial.print（“ ”）;

Serial.print（“Distance： ” ）;

Serial.println（DistanceMonitor）;

控制距離傳感器的功能：

int DistanceSensor（）{

//Local variables used only in this function

unsigned long TimeUsed;

unsigned long Wait;

unsigned long WaitExtra;

unsigned long TimeOpen;

bool Detected;

long Duration;

int Distance;

TimeUsed = micros（）; //Reads how long the arduino have been on in microseconds.

//Writes the local variables into global variables for monitoring

DetectedMonitor = Detected;

DistanceMonitor = Distance;

//Make the ultrasonic sensor send out a sonic wave and starts two timers.

//It is activated after 12 microseconds as the timer is exceeded and the function restarts.

if （WaitExtra 《 TimeUsed）{

digitalWrite（TrigPin，HIGH）; //Sends out a sonic wave

Wait = TimeUsed + 10; //Takes the current time and adds 10 microseconds to create a timer

WaitExtra = TimeUsed + 12; //Takes the current time and adds 12 to create a timer

}

//Turns off the sonic wave and reads how long it took for it to return.

//Afterwards it calculates the distance it have traveled.

//The distance is calculated in cm.

if （Wait 》= TimeUsed）{

digitalWrite（TrigPin，LOW）; // Stops the sonic wave

Duration = pulseIn（EchoPin，HIGH）; //Reads how long it took for the wave to return in microseconds.

Distance = Duration*0.034/2; //Calculates the distance

}

//Checks if anyone is within a certain distance.

//This can be changed depending on when you want it to trigger.

//Remember this can‘t be less than 2 cm （0.79 inches） unless you use a different sensor.

if （（Distance 》= 10） && （Distance 《= 30））{

Detected = 1; //Something is detected

}

else{

Detected = 0; //Nothing has been detected

}

//Allows the Distance_Close to be set if someone if within the distance set.

//Refreshes if something is detected again.

if （Detected == 1）{

TimeOpen = TimeUsed + 4000000; //Refreshes or sets the time that must pass to reset Distance_Close.

}

//Sets Distance_Close to 1， if the time set in detected hasn’t been exceed.

if （TimeOpen 》 TimeUsed）{

Distance_Close = 1;

}

//Sets Distance_Close to 0， if the time set in detected has been exceed.

if （TimeOpen 《= TimeUsed）{

Distance_Close = 0;

}

}

控制LCD的功能：

int LCD（）{

lcd.setCursor（0， 0）; //Begins writing at the top row， from the beginning

lcd.print（“Temperature： ”）; //Writes “temperature” on the LCD

lcd.print（TemperatureMonitor）; //Writes the number measured by the DHT

lcd.setCursor（0，1）; //Begins writig at the bottom row， from the beginning

lcd.print（“Humidity： ”）; //Writes “humidity” on the LCD

lcd.print（HumidityMonitor）; //Writes the number measured by the DHT

}

打開垃圾桶：

bool OpenTrashcan（） {

//If someone is detected within a set range in DistanceSensor， the trashcan open.

if （（TrashcanState == 0） && （Distance_Close == 1））{

//Sets the motor to run at full speed in a certain direction. In our case it is CLOCKWISE？？？

analogWrite（DCmotorIn1， 0）;

analogWrite（DCmotorIn2， 255）;

//Stops the entire program to make sure it doesn‘t stop while opening.

delay（600）;

//After the delay is over the motor is turned off.

analogWrite（DCmotorIn1， 0）;

analogWrite（DCmotorIn2， 0）;

//Tells the rest of the program that the trashcan is open.

TrashcanState = 1;

}

}

關(guān)閉垃圾桶的功能：

bool CloseTrashcan（） {

//Local variable to control the button.

int button;

button = digitalRead（9）; //Continually check if the button is pressed or not

//Local variable saved as a global varaible for monitoring

ButtonMonitor = button;

//If the trashcan is open and no one has been within the range of the DistanceSensor for the set time the trashcan closes.

if （（TrashcanState == 1） && （Distance_Close == 0））{

//Starts the motor at full power. It turns COUNTER CLOCKWISE？？？

analogWrite（DCmotorIn1， 255）;

analogWrite（DCmotorIn2， 0）;

}

//If the trashcan is open and the button is pressed， the trashcan will close.

if （（button == 1） && （TrashcanState == 1））{

//Stops the motor

analogWrite（DCmotorIn1， 0）;

analogWrite（DCmotorIn2， 0）;

TrashcanState = 0; //Sets the trashcan as open.

}

}

讀取溫度和濕度的函數(shù)：

int TempHumid（）{

//Local variables used only in this function

unsigned long TimeUsed;

unsigned long Wait;

TimeUsed = millis（）; //Counts how long the program have been running in millis

//Reads the temperature and humidity every 2.5 seconds.

if （Wait 《 TimeUsed）{

int Humidity;

int Temperature;

Humidity = dht.readHumidity（）; //Reads the current humidity in percentage.

Temperature = dht.readTemperature（）; //Reads the current temperature in celcius.

HumidityMonitor = Humidity; // The humidity is saved in a global variable for monitoring.

TemperatureMonitor = Temperature; // The temperature is saved in a global variable for monitoring.

Wait = TimeUsed + 2500; //Takes the current time and adds 2500 milliseconds to create a timer.

}

}

為了獲得靈感和幫助，我們使用了以下來源：

超聲波傳感器

https://howtomechatronics.com/tutorials/arduino/u.。.

DHT11

http://www.circuitbasics.com/how-to-set-up-the-dh。 。.

該代碼基于DHT庫提供的示例。它被命名為DHTtester。

L298電機驅(qū)動模塊

https://www.instructables.com/id/How-to-use-the-L 。..

LCD

https://www.arduino.cc/en/Tutorial/HelloWorld

第6步：評估

自動垃圾桶功能齊全，但還有很多不足之處。

第一個問題是它無法檢測何時打開。這可以通過安裝伺服而不是直流電機來解決，通過使用可以檢測何時打開的按鈕或類似物。

秒的問題是超聲波傳感器有角度和一些困難時間材料太吸音了。它可以通過使用PIR傳感器來解決。如果安裝了PIR傳感器，它可以成角度以便更有可能檢測到人。

代碼也缺少顯示何時應(yīng)該清空垃圾桶的部分以及可以判斷垃圾桶何時清空的部分被清空了。