Project: Simple gate system for kids

Weekend ini saya terinspirasi oleh anak kedua saya yang meminta tangan saya untuk menjadi portal buka-tutup untuk mobil mainannya. Terbesit dipikiran untuk membuat sesuatu, yaitu portal otomatis. Setelah mengecek toolbox, ternyata ada satu lagi unit ESP8266, satu hobby servo 1Kg, satu unit sensor ultrasonic HC-SR04 dan passive buzzer yang nganggur.

Prinsip kerjanya sangat sederhana, servo akan bergerak jika sensor ultrasonic mendeteksi benda dalam jangkauan yang ditentukan. Bahan lengkap yang diperlukan dapat dibeli di www.tokopedia.com, antara lain:

Bahan:

1x ESP8266 NodeMCU

1x Mini Servo Tower Pro 1Kg

1x Ultrasonic Sensor

1x Passive buzzer

1x resistor 680 ohm

1x resistor 1K ohm

1x protoboard

kabel secukupnya

Box bekas

Stik es krim

Lem / glue gun

Waktu pengerjaan: 120 menit

Hasil akhirnya bisa diliihat di posting instagram berikut ini:

Simple DIY toy gate system with beeping sound for kids. Cost < 85K IDR #esp8266 #microcontroller #toys #kids #micropython

A post shared by Andi Dinata (@mdinata) on Apr 1, 2017 at 3:34am PDT

Instruksi rangkaian:

Instruksi script dan penjelasannya:

#Simple gate system with ESP8266 and Micropython
#When object is at ultrasonic sensor defined range, then servo motor will be activated
#While the servo is moving, beeping sound is added at every single movement of the motor
#Script by Andi Dinata
#1 April 2017


from machine import Pin, PWM
import time

#Define the buzzer. Pin = D6 (GPIO12)
buzz=Pin(12,Pin.OUT)

#Define the onboard led. Pin = D4 (GPIO02).
#For onboard led, led.high() means off
led=Pin(2, Pin.OUT)
led.high()

#Define servo. Pin = D5 (GPIO14)
servo=PWM(Pin(14), freq=50)

#Setup Servo duty cycle data for each position.
min=35
max=110
range=max-min
step=180/range

#Setup and initiate the ultrasonic sensor Trigger Pin=D1 (GPIO05)
#Echo Pin D2 (GPIO04)
trig=Pin(5,Pin.OUT)
trig.low()
time.sleep_ms(2)
trig.high()
time.sleep_ms(10)
trig.low()

echo=Pin(4,Pin.IN)

#Set function for the beeping sound
def beep(s):
        buzz(1)
        time.sleep(s)
        buzz(0)
        time.sleep(s)
        
#Set function to move and close the portal. a for angle, s for speed of portal
#opening. For this example, the gate closes in 2 seconds after the servo reach
#its full movement.

        
def move(a,s):
    for i in range(min,(min+(int(a/step)))):
        servo.duty(i)
        time.sleep(s)
        beep(s)
    time.sleep(2)
    servo.duty(min)


#Main prograam loop. The ultrasonic is triggered continuously. When the calculated
#distance value is below the given threshold, then turn on the led and activate
#the servo.
    
while True:
  trig.high()
  time.sleep_ms(10)
  trig.low()
  
  while echo.value() == 0:
    pass
  start = time.ticks_us()

  while echo.value() == 1:
    pass
  stop = time.ticks_us()
  d = (stop - start) / 58
  print(d)

  if d < 6:
      led.low()
      move(80,0.05)
  led.high()   
  time.sleep(3)

Full script bisa didownload di Download page

Selamat mencoba.