Physical Computing - Ultrasonic Ranging, Matrix Keypad, Infrared Remote, and Hygrothermograph DHT11

In this lab, we will continue with another set of projects you can create with ESP32-WROVER. Instructions are given by Andrew J. Park, Ph.D..

We will use Freenove Ultimate Starter Kit for ESP32-WROVER which you can buy on Amazon. How to set up the kit and start uploading code you can find on Freenove.

If these projects seem too challenging you can try to do the Freenove tutorials. See them in the tutorials section ↓.

Project 1 - Ultrasonic Ranging, a passive buzzer, an LED

Date: 11/2/23

Instructions:

Design and construct a circuit with an ultrasonic ranging module (HC-SR04), a buzzer, an LED bar (or multiple LEDs), and other necessary electronic components. When an object gets close to the HCSR04, the circuit increases the number of lit LEDs and plays higher tones (i.e., (low) Do-Re-Mi-Fa-SoLa-Ti-Do (high)). When an object goes away from the HC-SR04, the circuit decreases the number of lit LEDs and plays lower tones.

Parts:

• ESP32-WROVER x1
• GPIO Extension Board x1 (optional)
• Breadboard x1
• Jumper M/M x9
• HC-SR04 x1
• NPN transistor x1
• Passive Buzzer x7
• Resistor 1kΩ x2
• LED eed x1

Ultrasonic Ranging, a passive buzzer, an LED Schema:

Ultrasonic Ranging, a passive buzzer, an LED Breadboard View:

Source Code:

project-1.py

from machine import Pin,PWM
import time

# init pins

trigPin=Pin(13,Pin.OUT,0)
echoPin=Pin(14,Pin.IN,0)
ledPin=PWM(Pin(25),30000) 
buzzerPin=PWM(Pin(18), 2000)

#############################################################
# used a class from Freenove Ultimate kit ESP32 tutorial 21.1
#############################################################
soundVelocity=340
distance=0

def getSonar():
    trigPin.value(1)
    time.sleep_us(10)
    trigPin.value(0)
    while not echoPin.value():
        pass
    pingStart=time.ticks_us()
    while echoPin.value():
        pass
    pingStop=time.ticks_us()
    pingTime=time.ticks_diff(pingStop,pingStart)
    distance=pingTime*soundVelocity//2//30000
    return int(distance)
   
# used from https://github.com/hibit-dev/buzzer/blob/master/lib/pitches.zip
NOTES = {
    "B0": 31, "C1": 33, "CS1": 35, "D1": 37, "DS1": 39, "E1": 41, "F1": 44, "FS1": 46,
    "G1": 49, "GS1": 52, "A1": 55, "AS1": 58, "B1": 62, "C2": 65, "CS2": 69, "D2": 73,
    "DS2": 78, "E2": 82, "F2": 87, "FS2": 93, "G2": 98, "GS2": 104, "A2": 110, "AS2": 117,
    "B2": 123, "C3": 131, "CS3": 139, "DB3": 139, "D3": 147, "DS3": 156, "EB3": 156,
    "E3": 165, "F3": 175, "FS3": 185, "G3": 196, "GS3": 208, "A3": 220, "AS3": 233,
    "B3": 247, "C4": 262, "CS4": 277, "D4": 294, "DS4": 311, "E4": 330, "F4": 349,
    "FS4": 370, "G4": 392, "GS4": 415, "A4": 440, "AS4": 466, "B4": 494, "C5": 523,
    "CS5": 554, "D5": 587, "DS5": 622, "E5": 659, "F5": 698, "FS5": 740, "G5": 784,
    "GS5": 831, "A5": 880, "AS5": 932, "B5": 988, "C6": 1047, "CS6": 1109, "D6": 1175,
    "DS6": 1245, "E6": 1319, "F6": 1397, "FS6": 1480, "G6": 1568, "GS6": 1661, "A6": 1760,
    "AS6": 1865, "B6": 1976, "C7": 2093, "CS7": 2217, "D7": 2349, "DS7": 2489, "E7": 2637,
    "F7": 2794, "FS7": 2960, "G7": 3136, "GS7": 3322, "A7": 3520, "AS7": 3729, "B7": 3951,
    "C8": 4186, "CS8": 4435, "D8": 4699, "DS8": 4978, "REST": 0
}  

def buzzer(note):
    buzzerPin.init()       
    buzzerPin.freq(note)
    time.sleep_ms(500)
    buzzerPin.deinit()

while True:
    distance = getSonar()
    time.sleep_ms(300)
    

    if distance:
        print(distance)

        if distance < 3:
            print('Do')
            ledPin.duty(125)
            buzzer(NOTES['A3'])
           
        elif distance >= 3 and distance < 7: #1
            print('Re')
            ledPin.duty(250)
            buzzer(NOTES['B3'])
            
        elif distance >= 7 and distance < 10: #1
            print('Mi')
            ledPin.duty(375)
            buzzer(NOTES['C3'])
            
        elif distance >= 10 and distance < 13: #2
            print('Fa')
            ledPin.duty(500) 
            buzzer(NOTES['D3'])
            
        elif distance == 13 and distance < 16: #3
            print('So')
            ledPin.duty(625)
            buzzer(NOTES['E3'])
            
        elif distance >= 16 and distance < 20: #3
            print('La')
            ledPin.duty(750)
            buzzer(NOTES['F3'])

        elif distance >= 20 and distance < 25: #3
            print('Ti')
            ledPin.duty(875)
            buzzer(NOTES['G3'])
            
    buzzerPin.deinit()

Youtube video ↓ (click on it)

Project 2 - Infrared remote and components to turn on

Date: 11/2/23

Instructions:

Design and construct a circuit with an infrared remote, a buzzer, a motor (DC motor, servo motor, or stepper motor), a NeoPixel, and an LCD1602. By pressing various buttons on the infrared remote, their corresponding electronic components respond with some sound, spinning, light LEDs, or a message on the display. Capture your settings and working circuit in photos and videos (the videos should include sound).

Parts:

• ESP32-WROVER x1
• GPIO Extension Board x1 (optional)
• Breadboard x1
• LCD 1602 x1
• Jumper M/M x19
• Servo x1
• Neopixel 1x
• NPN transistor x1
• Passive Buzzer x7
• Thermistor x1
• Resistor 1kΩ x2
• Resistor 10kΩ x1

Infrared remote and components to turn on schema:

Infrared remote and components to turn on Breadboard View:

Source Code:

project-2.py

from machine import Pin, I2C, PWM
import time
from lcd import I2C, I2cLcd
from infrared import irGetCMD
from song import playSong
from neop import neoRun
from myservo import myServo

servo=myServo(19) #set servo pin
servo.myServoWriteAngle(0) #Set Servo Angle
time.sleep_ms(1000)


i2c = I2C(scl=Pin(33), sda=Pin(32), freq=400000)
devices = i2c.scan()
if len(devices) == 0:
    print("No i2c device !")
else:
    for device in devices:
        print("I2C addr: "+hex(device))
        lcd = I2cLcd(i2c, device, 2, 16)

#############################################################
# Project Code
#############################################################

ledPin=PWM(Pin(25),10000)  # LED

recvPin = irGetCMD(15) # Remote
passiveBuzzer = PWM(Pin(13), 2000) # buzzer
ledPin.duty(1)
passiveBuzzer.deinit()

while True:
    value = recvPin.ir_read()
    if value:
        if value == '0xff6897':   #Message
            print('0')
            lcd.putstr("Made by \nAdam Boucek")
            time.sleep_ms(2000)
            lcd.putstr("")
        elif value == '0xff30cf': #LED
            print('1')
            ledPin.duty(1000)
        elif value == '0xff18e7': #Song
            print('2')
            playSong(passiveBuzzer)
        elif value == '0xff7a85': #Servo
            print('3')
            for i in range(0,180,1):
                servo.myServoWriteAngle(i)
                time.sleep_ms(15)
            for i in range(180,0,-1):
                servo.myServoWriteAngle(i)
                time.sleep_ms(15)  
        elif value == '0xff10ef': #NEOPixel
            print('4')
            neoRun()

Youtube video ↓ (click on it)

Tutorials

To move forward I can show you what cool things you can make with the Freenove tutorials. They are well-guided and a lot of fun.

Tutorial No.	Gif
21.1
21.2
22.1
22.2
23.1
23.2
24.1
24.2