Capteur de distance Micro:bit Projet Servomoteur

Réalisation d’un radar contrôlé par Micro:bit

29-10-21 1872

But de ce projet:

Le radar a été développé comme méthode de détection des avions ennemis pendant la Seconde Guerre mondiale.

Parallèlement aux développements technologiques, il est aujourd’hui utilisé dans un large éventail de secteurs. Depuis les dernières décennies, il y a eu des progrès significatifs dans l’utilisation de la technologie radar.

Dans ce projet, nous allons concevoir un radar utilisant la care Micro:bit et un capteur à ultrasons pour la détection.

Ce projet vise à réaliser un prototype de système radar qui détecte les objets fixes et mobiles.

Fonctionnement du radar contrôlé par Microbit:

Composants nécessaires

Carte Micro:bit
Capteur HC-SR04
Servo moteur
Carte GPIO

Montage:

Pour faire le montage, on a connecté:

Pour le capteur sonore HC-SR04 :

la broche VCC à la broche 3.3V du Micro:bit
la broche Trig à la broche P2 du Micro:bit
la broche ECHO à la broche P1 du Micro:bit
la broche GND à la broche GND du Micro:bit

Pour le servomoteur:

fil rouge : fil de l’alimentation à relier à la borne 5V de la carte GPIO
fil marron : fil à relier à la broche GND du Micro:bit
Jaune : fil de signal de positionnement branché à la broche P0 du Micro:bit

Programme makecode

Voici le programme makecode qui permet de :

calculer la distance entre le capteur HC-SR04 et l’objet détecté
faire tourner le servomoteur
d’envoyer des données (position du servomoteur et la distance) de la carte Micro:bit vers l’ordinateur.

Télécharger le programme

Programme Python exécuté par l’ordinateur

# Python + Microbit-based Radar Plotter
#
# ** Works with any motor that outputs angular rotation
# ** and with any distance sensor (HC-SR04, VL53L0x,LIDAR)
#
import numpy as np
import matplotlib
matplotlib.use('TkAgg')
import matplotlib.pyplot as plt
from matplotlib.widgets import Button
import serial,sys,glob
import serial.tools.list_ports as COMs
#
#
############################################
# Find Microbit ports, select one, then start communication with it
############################################
#

port1="COM19"
ser = serial.Serial(port1,baudrate=115200)
ser.flush() # clear the port
#
############################################
# Start the interactive plotting tool and
# plot 180 degrees with dummy data to start
############################################
#
fig = plt.figure(facecolor='k')
win = fig.canvas.manager.window # figure window
screen_res = win.wm_maxsize() # used for window formatting later
dpi = 150.0 # figure resolution
fig.set_dpi(dpi) # set figure resolution

# polar plot attributes and initial conditions
ax = fig.add_subplot(111,polar=True,facecolor='#006d70')
ax.set_position([-0.05,-0.05,1.1,1.05])
r_max = 100.0 # can change this based on range of sensor
ax.set_ylim([0.0,r_max]) # range of distances to show
ax.set_xlim([0.0,np.pi]) # limited by the servo span (0-180 deg)
ax.tick_params(axis='both',colors='w')
ax.grid(color='w',alpha=0.5) # grid color
ax.set_rticks(np.linspace(0.0,r_max,5)) # show 5 different distances
ax.set_thetagrids(np.linspace(0.0,180.0,10)) # show 10 angles
angles = np.arange(0,181,1) # 0 - 180 degrees
theta = angles*(np.pi/180.0) # to radians
dists = np.ones((len(angles),)) # dummy distances until real data comes in
pols, = ax.plot([],linestyle='',marker='o',markerfacecolor = 'w',
                 markeredgecolor='#EFEFEF',markeredgewidth=1.0,
                 markersize=10.0,alpha=0.9) # dots for radar points
line1, = ax.plot([],color='w',
                  linewidth=4.0) # sweeping arm plot

# figure presentation adjustments
fig.set_size_inches(0.96*(screen_res[0]/dpi),0.96*(screen_res[1]/dpi))
plot_res = fig.get_window_extent().bounds # window extent for centering
win.wm_geometry('+{0:1.0f}+{1:1.0f}'.\
                format((screen_res[0]/2.0)-(plot_res[2]/2.0),
                       (screen_res[1]/2.0)-(plot_res[3]/2.0))) # centering plot
fig.canvas.toolbar.pack_forget() # remove toolbar for clean presentation
fig.canvas.set_window_title('Microbit Radar')

fig.canvas.draw() # draw before loop
axbackground = fig.canvas.copy_from_bbox(ax.bbox) # background to keep during loop

############################################
# button event to stop program
############################################

def stop_event(event):
    global stop_bool
    stop_bool = 1
prog_stop_ax = fig.add_axes([0.85,0.025,0.125,0.05])
pstop = Button(prog_stop_ax,'Stop Program',color='#FCFCFC',hovercolor='w')
pstop.on_clicked(stop_event)
# button to close window
def close_event(event):
    global stop_bool,close_bool
    if stop_bool:
        plt.close('all')
    stop_bool = 1
    close_bool = 1
close_ax = fig.add_axes([0.025,0.025,0.125,0.05])
close_but = Button(close_ax,'Close Plot',color='#FCFCFC',hovercolor='w')
close_but.on_clicked(close_event)

fig.show()

############################################
# inifinite loop, constantly updating the
# 180deg radar with incoming Microbit data
############################################
#
start_word,stop_bool,close_bool = True,False,False
while True:
    try:
        if stop_bool: # stops program
            fig.canvas.toolbar.pack_configure() # show toolbar
            if close_bool: # closes radar window
                plt.close('all')
            break
        ser_bytes = ser.readline() # read Microbit serial data
        decoded_bytes = ser_bytes.decode('utf-8') # decode data to utf-8
        #data =ser_bytes.decode('utf-8')
        #print(data.split(','))
        data = (decoded_bytes.replace('\r','')).replace('\n','').replace(' ','')
        #print(data.split(','))
        if start_word:
            vals = [float(ii) for ii in data.split(',')]
            print(vals)
            if len(vals)<2:
                continue
            angle,dist = vals # separate into angle and distance
            if dist>r_max:
                dist = 0.0 # measuring more than r_max, it's likely inaccurate
            dists[int(angle)] = dist
            if angle % 5 ==0: # update every 5 degrees
                pols.set_data(theta,dists)
                fig.canvas.restore_region(axbackground)
                ax.draw_artist(pols)

                line1.set_data(np.repeat((angle*(np.pi/180.0)),2),
                   np.linspace(0.0,r_max,2))
                ax.draw_artist(line1)

                fig.canvas.blit(ax.bbox) # replot only data
                fig.canvas.flush_events() # flush for next plot
        else:
            if data=='Radar Start': # stard word on Arduno
                start_word = True # wait for Microbit to output start word
                print('Radar Starting...')
            else:
                continue

    except KeyboardInterrupt:
        plt.close('all')
        print('Keyboard Interrupt')
        break

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# Python + Microbit-based Radar Plotter

# ** Works with any motor that outputs angular rotation

# ** and with any distance sensor (HC-SR04, VL53L0x,LIDAR)

import numpy as np

import matplotlib

matplotlib.use('TkAgg')

import matplotlib.pyplot as plt

from matplotlib.widgets import Button

import serial,sys,glob

import serial.tools.list_ports as COMs

############################################

# Find Microbit ports, select one, then start communication with it

############################################

port1="COM19"

ser = serial.Serial(port1,baudrate=115200)

ser.flush() # clear the port

############################################

# Start the interactive plotting tool and

# plot 180 degrees with dummy data to start

############################################

fig = plt.figure(facecolor='k')

win = fig.canvas.manager.window # figure window

screen_res = win.wm_maxsize() # used for window formatting later

dpi = 150.0 # figure resolution

fig.set_dpi(dpi) # set figure resolution

# polar plot attributes and initial conditions

ax = fig.add_subplot(111,polar=True,facecolor='#006d70')

ax.set_position([-0.05,-0.05,1.1,1.05])

r_max = 100.0 # can change this based on range of sensor

ax.set_ylim([0.0,r_max]) # range of distances to show

ax.set_xlim([0.0,np.pi]) # limited by the servo span (0-180 deg)

ax.tick_params(axis='both',colors='w')

ax.grid(color='w',alpha=0.5) # grid color

ax.set_rticks(np.linspace(0.0,r_max,5)) # show 5 different distances

ax.set_thetagrids(np.linspace(0.0,180.0,10)) # show 10 angles

angles = np.arange(0,181,1) # 0 - 180 degrees

theta = angles*(np.pi/180.0) # to radians

dists = np.ones((len(angles),)) # dummy distances until real data comes in

pols, = ax.plot([],linestyle='',marker='o',markerfacecolor = 'w',

markeredgecolor='#EFEFEF',markeredgewidth=1.0,

markersize=10.0,alpha=0.9) # dots for radar points

line1, = ax.plot([],color='w',

linewidth=4.0) # sweeping arm plot

# figure presentation adjustments

fig.set_size_inches(0.96*(screen_res[0]/dpi),0.96*(screen_res[1]/dpi))

plot_res = fig.get_window_extent().bounds # window extent for centering

win.wm_geometry('+{0:1.0f}+{1:1.0f}'.\

format((screen_res[0]/2.0)-(plot_res[2]/2.0),

(screen_res[1]/2.0)-(plot_res[3]/2.0))) # centering plot

fig.canvas.toolbar.pack_forget() # remove toolbar for clean presentation

fig.canvas.set_window_title('Microbit Radar')

fig.canvas.draw() # draw before loop

axbackground = fig.canvas.copy_from_bbox(ax.bbox) # background to keep during loop

############################################

# button event to stop program

############################################

def stop_event(event):

global stop_bool

stop_bool = 1

prog_stop_ax = fig.add_axes([0.85,0.025,0.125,0.05])

pstop = Button(prog_stop_ax,'Stop Program',color='#FCFCFC',hovercolor='w')

pstop.on_clicked(stop_event)

# button to close window

def close_event(event):

global stop_bool,close_bool

if stop_bool:

plt.close('all')

stop_bool = 1

close_bool = 1

close_ax = fig.add_axes([0.025,0.025,0.125,0.05])

close_but = Button(close_ax,'Close Plot',color='#FCFCFC',hovercolor='w')

close_but.on_clicked(close_event)

fig.show()

############################################

# inifinite loop, constantly updating the

# 180deg radar with incoming Microbit data

############################################

start_word,stop_bool,close_bool = True,False,False

while True:

try:

if stop_bool: # stops program

fig.canvas.toolbar.pack_configure() # show toolbar

if close_bool: # closes radar window

plt.close('all')

break

ser_bytes = ser.readline() # read Microbit serial data

decoded_bytes = ser_bytes.decode('utf-8') # decode data to utf-8

#data =ser_bytes.decode('utf-8')

#print(data.split(','))

data = (decoded_bytes.replace('\r','')).replace('\n','').replace(' ','')

#print(data.split(','))

if start_word:

vals = [float(ii) for ii in data.split(',')]

print(vals)

if len(vals)<2:

continue

angle,dist = vals # separate into angle and distance

if dist>r_max:

dist = 0.0 # measuring more than r_max, it's likely inaccurate

dists[int(angle)] = dist

if angle % 5 ==0: # update every 5 degrees

pols.set_data(theta,dists)

fig.canvas.restore_region(axbackground)

ax.draw_artist(pols)

line1.set_data(np.repeat((angle*(np.pi/180.0)),2),

np.linspace(0.0,r_max,2))

ax.draw_artist(line1)

fig.canvas.blit(ax.bbox) # replot only data

fig.canvas.flush_events() # flush for next plot

else:

if data=='Radar Start': # stard word on Arduno

start_word = True # wait for Microbit to output start word

print('Radar Starting...')

else:

continue

except KeyboardInterrupt:

plt.close('all')

print('Keyboard Interrupt')

break

Vous pouvez voir aussi

Construction des objets connectés basés sur Micro:bit

02-10-22

Cahier d’activités pour la carte Micro:bit

18-09-22

1 commentaire

Moyon 05-04-2222

Comment faire communiquer la micro-bit avec le simulateur makecode (donc avec l'ordi) pour tracer la courbe avec le simulateur, une fois le programme chargé dans la carte ?