Raspberry Pi - 블루투스 통신 (btsocket.py)

라즈베리파이 블루투스 통신

관련 패키지 설치

• sudo apt-get install -y bluetooth blueman bluez
• sudo apt-get install -y python-bluetooth
• pip3 install pybluez
• sudo reboot

블루투스 장치 페어링

$ bluetoothctl

[bluetooth]# scan on
Discovery started
[CHG] Controller DC:A6:32:AC:76:8E Discovering: yes
[NEW] Device E4:7D:BD:A4:DD:C5 [TV] Samsung Q7 Series (55)
[NEW] Device 98:D3:51:F9:42:AE HC-05
[NEW] Device 3C:77:E6:CD:A7:FE DESKTOP-K3PUDE3
[NEW] Device 00:51:ED:8D:47:1B S60UPI
[bluetooth]# pair 98:D3:51:F9:42:AE
[CHG] Device 98:D3:51:F9:42:AE Connected: yes
Request PIN code
[agent] Enter PIN code: 1234
[CHG] Device 98:D3:51:F9:42:AE UUIDs: 00001101-0000-1000-8000-00805f9b34fb
[CHG] Device 98:D3:51:F9:42:AE ServicesResolved: yes
[CHG] Device 98:D3:51:F9:42:AE Paired: yes
Pairing successful
[bluetooth]# agent on
[bluetooth]# default-agent
[bluetooth]# exit

라즈베리파이 -> 아두이노

bt_ex01.py

from bluetooth import * 

LINE_END =  "\r\n"

# Create the client socket 
client_socket=BluetoothSocket( RFCOMM ) 
client_socket.connect(("00:18:91:D7:67:13", 1))  # 접속 

try:
    while True: 
        msg = input("Send : ") + LINE_END 
        client_socket.send(msg)     # 전송
except KeyboardInterrupt:
    print("Finished")

client_socket.close() 

아두이노 -> 라즈베리파이

bt_ex02.py

from bluetooth import * 

LINE_END =  "\r\n"

# Create the client socket 
client_socket=BluetoothSocket( RFCOMM ) 
client_socket.connect(("00:18:91:D7:67:13", 1))  # 접속 

try:
    while True: 
        msg = input("Send : ") + LINE_END 
        client_socket.send(msg)     # 전송

        msg = client_socket.recv(1024)  # 수신
        print(f"recived message : {msg}")
except KeyboardInterrupt:
    print("Finished")

client_socket.close() 

딜레이가 없어서 제대로 전달되지 않음

btsocket.py

from bluetooth import * 

class BtSocket(BluetoothSocket) :
    def __init__(self, *args):  # 위치기반 매개변수
        super().__init__(*args)
        self.buf = ''

    def readline(self):
        ix = self.buf.find('\r\n')  # 개행문자 체크
        if ix != -1 :
            line = self.buf[:ix]
            self.buf = self.buf[ix+2:]
            return line

        self.buf += self.recv(1024).decode()
        return self.readline()

bt_ex02_2.py

from bluetooth import * 
from btsocket import BtSocket

LINE_END =  "\r\n"

# Create the client socket 
# client_socket=BluetoothSocket( RFCOMM ) 
client_socket=BtSocket( RFCOMM )
client_socket.connect(("00:18:91:D7:67:13", 1))  # 접속 

try:
    while True: 
        msg = input("Send : ") + LINE_END 
        client_socket.send(msg)     # 전송

        # msg = client_socket.recv(1024)  # 수신
        msg = client_socket.readline()
        print(f"recived message : {msg}")
except KeyboardInterrupt:
    print("Finished")

client_socket.close() 

서보 모터 제어

• AngularServo
  • 각도로 서보모터를 조정하는 클래스
  • 180도 조정 범위 설정
  • AngularServo(25, min_angle=-90, max_angle=90, min_pulse_width=0.0006, max_pulse_width=0.0024)

아두이노 블루투스 컨트롤러 연계

bt_ex03.py

from btsocket import BtSocket
from bluetooth import * 
from gpiozero import AngularServo

servo = AngularServo(25, min_angle=-90, max_angle=90, 
                     min_pulse_width=0.0006, max_pulse_width=0.0024)

def control(tokens):
    command = int(tokens[0])
    if command == 0 : # 주행모드
        x = int(tokens[1])
        y = int(tokens[2])
    elif command == 1 : #카메라 모드
        angle = int(tokens[1])
        servo.angle = angle

RFADDR = "00:18:91:D7:67:13"
client_socket=BtSocket( RFCOMM ) 
client_socket.connect((RFADDR, 1)) 

try:
    while True:
        line = client_socket.readline()  # 동기 함수
        print(line)
        control(line.split(','))
except KeyboardInterrupt:
    print("Finished")

client_socket.close() 

아두이노 - 라즈베리파이 간 블루투스 송수신 및 서보모터 동작 확인