학원 51일차 복습(5/31)

이론

***pulse_duration * 17000 ?***

속도 공식(속도 = 거리 / 시간)에 따라, 속도(340m/s라고 함) = 거리(x) / 시간(duration/2)

duration/2 : 초음파센서의 원리가 초음파를 내보내고(1번) 돌아오기까지의(2번) 시간을 측정하는 것이므로 거리를 2번지난것과 같음

따라서 거리(x) = 속도(340) * 시간(duration/2)

duartion * (340m/s / 2) -> duration * (170m/s) -> m를 cm로 바꾸면 -> duration * 17000

[Flask(플라스크) 서버 구축]

sudo pip3 install flask  

*** index.html 코드 내용도 정상, 파일경로도 정상인데 자꾸 Internal Server Error가 뜨면, 넷빈즈에서 Webbrower로 새 프로젝트 만든후, 디폴트로 생기는 index.html에 작성해서 fileZilla로 업로드 해볼것!!! ***

실습

hc_demo.py

import RPi.GPIO as gpio import time gpio.setmode(gpio.BCM) trig = 13 echo = 19 led_pin = 18 buz_pin=12 print("start") gpio.setwarnings(False) gpio.setup(trig,gpio.OUT) gpio.setup(led_pin, gpio.OUT) gpio.setup(echo, gpio.IN) gpio.setup(buz_pin, gpio.OUT) try: while True: gpio.output(trig, False) time.sleep(0.5) gpio.output(trig, True) time.sleep(0.00001) gpio.output(trig, False) pulse_end = 0 pulse_start = 0 while gpio.input(echo) == 0: pulse_start = time.time() while gpio.input(echo) == 1: pulse_end = time.time() pulse_duration = pulse_end - pulse_start distance = pulse_duration * 17000 distance = round(distance,2) if distance >= 10: #cm gpio.output(led_pin,False) gpio.output(buz_pin,False) else: gpio.output(led_pin, True) gpio.output(buz_pin, True) print("Distance : ", distance, "cm") except KeyboardInterrupt as e: print(e) finally: print("clean up...") gpio.cleanup()

hcr0531_java

package ultrawave0531; import java.io.IOException; import java.util.logging.Level; import java.util.logging.Logger; import jdk.dio.gpio.GPIOPin; public class Hcr0531 { public static int getDistance(GPIOPin trigPin, GPIOPin echoPin){ int distance = 0; try { //펄스를 10마이크로초 동안 발생 trigPin.setValue(true); Thread.sleep(0, 10000); trigPin.setValue(false); //high 수신 시작일 때 시간 측정 while(echoPin.getValue() ==false){} double startTime = System.nanoTime(); //low 수신 시작일 때 시간 측정 while(echoPin.getValue() ==true){} double endTime = System.nanoTime(); double distance_val = (endTime - startTime)/1000000000/2; distance = (int) (distance_val * 34000); //cm단위 } catch (Exception ex) { ex.printStackTrace(); } return distance; } }

FXMLDocumentController.java

package ultrawave0531; import java.io.IOException; import java.net.URL; import java.util.ResourceBundle; import java.util.logging.Level; import java.util.logging.Logger; import javafx.application.Platform; import javafx.event.ActionEvent; import javafx.fxml.FXML; import javafx.fxml.Initializable; import javafx.scene.control.Label; import jdk.dio.ClosedDeviceException; import jdk.dio.DeviceManager; import jdk.dio.gpio.GPIOPinConfig; import jdk.dio.gpio.GPIOPin; /** * * @author kosta */ public class FXMLDocumentController implements Initializable { @FXML private Label lbDistance; private boolean flag; private LED led; private LED buz; @FXML private void handleButtonAction(ActionEvent event) { try { led = new LED(27); buz = new LED(12); System.out.println("You clicked me!"); GPIOPin trigPin = DeviceManager.open(new GPIOPinConfig.Builder() .setPinNumber(13) .setDirection(GPIOPinConfig.DIR_OUTPUT_ONLY).build()); //gpio.setup(변수명, gpio.OUT)와 동일 GPIOPin echoPin = DeviceManager.open(new GPIOPinConfig.Builder() .setPinNumber(19) .setDirection(GPIOPinConfig.DIR_INPUT_ONLY).build()); //스레드!!! Thread th = new Thread(new Runnable() { @Override public void run() { System.out.println("thread start..."); while (!flag) { try { Thread.sleep(200); } catch (Exception e) { } int distance = Hcr0531.getDistance(trigPin, echoPin); Platform.runLater(new Runnable() { @Override public void run() { try { if (distance < 10) { led.on(); buz.on(); } else { led.off(); buz.off(); } } catch (Exception e) { } lbDistance.setText(String.valueOf(distance)); } }); }//while문 끝 try { trigPin.close(); echoPin.close(); } catch (IOException ex) { } } }); th.setDaemon(true); th.start(); } catch (Exception ex) { } //종료시... Runtime.getRuntime().addShutdownHook(new Thread(){ @Override public void run() { try { led.close(); buz.close(); } catch (IOException ex) { } } }); } @Override public void initialize(URL url, ResourceBundle rb) { try { } catch (Exception ex) { } } }

web_server.py

from flask import Flask app = Flask(__name__) @app.route('/') def index(): return "This is main page" @app.route('/sub') def sub(): return "This is sub page" @app.route('/led/<state>') def led(state): if state == "on" or state == "off": str = "Led is now %s." %state else: str = "Invalid Pages" return str if __name__ == "__main__": print("Webserver stasrts...") app.run(host="192.168.0.164")

web_server2.py

from flask import Flask, render_template, request import RPi.GPIO as GPIO GPIO.setmode(GPIO.BCM) GPIO.setwarnings(False) buz_pin = 12 # buz GPIO.setup(buz_pin, GPIO.OUT) app=Flask(__name__) @app.route('/') def index(): return render_template('index.html') #index.html에서 on/off를 클릭 했을 경우 파라미터를 처리하기 위한 route @app.route('/param',methods=['GET','POST']) def params(): if request.method == 'GET': paramv = request.args.get('status', '') print('status:'+paramv) if paramv == "on": GPIO.output(buz_pin, True) elif paramv == "off": GPIO.output(buz_pin,False) return paramv if __name__ =='__main__': print('Webserver starts') app.run(host='0.0.0.0')