短学期要我们做一个项目，我看网上红外防坠落小车还是有点资料的，所以就选了，想着也许比较简单，而且实验室也有学长流传下来的小车，电机、电池、轮子、esp32都连好了，其实只要给板子写一些逻辑就行了。学长很贴心，把它们造小车的技术文档都发给我了，但是是用arduino写的，而我们是要用micropython写，对于他的那个电机驱动模块的频率什么的我都看不懂，我尝试了312500Hz，100000Hz，1000Hz好像都能动，而且速度也一样，不知道频率代表了什么，我同学说，如果esp32是40M，而我这个电机模块是20M的话，我的duty就只能填0,512,1023，也就是20M/40M=1/2，整个1 的数字信号被分成了两部分，我的duty可以写相对于1023的0（0）、 一半（512）、全部（1023）.而如果电机填了2M，那么整个1被分成了40M/2M=20份，每一份是1024/20=51.2,也就是我的duty可以填0, 51.2, 51.2×2，51.2×3 … 51.2×20，也就是速度被分成了20档。
但是我没管那么多，为了简单，我直接把duty设置为1023，就是全速。
小车是用flutter写的控制小车的app控制的，功能只有前后左右和刹车，还有往前开或者往后开的时候，如果发现前面是悬崖，就直接刹车。
至于硬件方面，我好像没做什么，因为小车是现成的，我只是连了两个红外传感器，VCC连3V3，GND连GND，D0连G26。另外一个VCC的杜邦线把皮扒了，露出了里面的铜丝，和之前的VCC的线连起来，一起连了3V3，也可以直接连5V的。GND连GND，D0连G25.
import machine
from machine import PWM ,Pin
import utime
import time
from umqtt.simple import MQTTClient
import ubinascii
import network
import dht
from machine import Timer
from machine import UART
# right wheel
p1 =Pin(27 ,Pin.OUT)
p2 =Pin(14 ,Pin.OUT)
# left wheel
p3 =Pin(21 ,Pin.OUT)
p4 =Pin(33 ,Pin.OUT)
v_left =Pin(16)
v_right =Pin(17)
v_right_pwm =PWM(Pin(17) ,freq=312500 ,duty=512 ) # pwm 速度 right
v_left_pwm =PWM(Pin(16) ,freq=312500,duty=512 ) # pwm 速度 left
infra_red_receive =Pin(5,Pin.IN)
infra_red_receive_pwm =PWM(infra_red_receive)
def Forward_speed_regulation(which,speed):#正转调速
if which=='left':
p3.value(1)
p4.value(0)
v_left_pwm.duty(speed)
else:
p1.value(1)
p2.value(0)
v_right_pwm.duty(speed)
def Back_speed_regulation(which,speed):
if which=='left':
p3.value(0)
p4.value(1)
v_left_pwm.duty(speed)
else:
p1.value(0)
p2.value(1)
v_right_pwm.duty(speed)
def turn_left():
Back_speed_regulation('left',1023)
Forward_speed_regulation('right',1023)
def turn_right():
Forward_speed_regulation('left',1023)
Back_speed_regulation('right',1023)
def back():
Back_speed_regulation('left',1023)
Back_speed_regulation('right',1023)
def forward():
Forward_speed_regulation('left',1023)
Forward_speed_regulation('right',1023)
def full_speed_forward_tyre(which):
if which=='left':
p3.value(1)
p4.value(0)
v_left.on()
else:
p1.value(1)
p2.value(0)
v_right.on()
def full_speed_back_tyre(which):
if which=='left':
p3.value(0)
p4.value(1)
v_left.on()
else:
p1.value(0)
p2.value(1)
v_right.on()
def full_speed_forward():
full_speed_forward_tyre('left')
full_speed_forward_tyre('right')
def full_speed_back():
full_speed_back_tyre('left')
full_speed_back_tyre('right')
def full_speed_left():
full_speed_back_tyre('left')
full_speed_forward_tyre('right')
def full_speed_right():
full_speed_forward_tyre('left')
full_speed_back_tyre('right')
def brake():
p1.off()
p2.off()
p3.off()
p4.off()
SERVER = '你的服务器' # MQTT服务器
CLIENT_ID = ubinascii.hexlify(machine.unique_id()) # 获取ESP32的ID
PHONE_TOPIC = b'你的接收的topic' # TOPIC的ID
username = '你的账号' # 账号，随便写
password = '你的密码' # 密码，随便写
PUBLISH_TOPIC =b'你的发出去的topic'
def send_msg(msg):
client.publish(PUBLISH_TOPIC ,msg)
def set_client():
global client,client_infra_red
client = MQTTClient(CLIENT_ID, SERVER, 0, username, password, 60)
client.set_callback(mqtt_callback)
client.connect()
client.subscribe(PHONE_TOPIC)
state=b'0'
car_state=b'brake'
def mqtt_callback(topic, msg):
global state,car_state
if msg==b'0' or msg==b'1' or msg==b'2' or msg==b'3':
state=msg
if msg==b'2' or msg==b'3':
if car_state==b'forward':
brake()
print('save')
if msg==b'1' or msg==b'3':
if car_state==b'back':
brake()
print('save back')
#state是红外线传过来的状态，有以下表示
#0 forward can , back can ，可以前进也可以后退
#1 forward can , back not
#2 forward not , back can
#3 forward not , back not
if msg==b'brake':
print('brake')
send_msg('brake')
brake()
car_state=b'brake'
elif msg==b'left':
print('turn left')
send_msg('turn left')
full_speed_left()
elif msg==b'right':
print('turn right')
send_msg('turn right')
full_speed_right()
elif msg==b'back':
#0 forward can , back can
#1 forward can , back not
#2 forward not , back can
#3 forward not , back not
if state==b'1' or state==b'3':
send_msg('Cliff there, you want me to die?')
print('Cliff there, you want me to die?')
brake()
car_state=b'brake'
else :
print('back')
send_msg('back')
back()
car_state=b'back'
elif msg==b'forward':
if state==b'3' or state==b'2':
send_msg('Cliff over there, you want me to die?')
print('Cliff over there, you want me to die?')
brake()
car_state=b'brake'
else: # 红外没发现悬崖，才能前进
print('forward')
send_msg('forward')
forward()
car_state=b'forward'
def check():
global time_ok,ok
print('check')
while True:
# 查看是否有数据传入
# 有的话就执行 mqtt_callback
#client_infra_red.check_msg()
client.check_msg()
utime.sleep_ms(100 )
def connect_to_wifi():
wifi = network.WLAN(network.STA_IF) # 创建一个网络接口
if not wifi.isconnected():
wifi.active(True ) # 激活网络接口
wifi.disconnect( ) # 中断之前连接的wifi
wifi.connect('你的网络名字' ,'你的网络密码') # 输入账号密码连接网络
while(wifi.ifconfig()[0 ]=='0.0.0.0'):
time.sleep(1)
print(wifi.ifconfig())
def test():
full_speed_back()
utime.sleep(1)
brake()
utime.sleep(1)
full_speed_forward()
utime.sleep(1)
brake()
#infra_red_test()
def init_net():
print('connecting to the car')
connect_to_wifi()
set_client()
print('connecting completed')
send_msg('are you my master?')
check()
def test_velocity_move():
forward()
utime.sleep(1)
brake()
utime.sleep(1)
back()
utime.sleep(1)
brake()
utime.sleep(1)
turn_left()
utime.sleep(1)
turn_right()
time.sleep(1)
brake()
#test_velocity_move()
init_net()红外线的main，因为小车上的esp32已经插满了，所以用单独一块板作为红外线的
import machine
from machine import PWM ,Pin
import utime
import time
from umqtt.simple import MQTTClient
import ubinascii
import network
import ubinascii
import dht
from machine import Timer
infra_red_receive = Pin(26, Pin.IN)
infra_red_receive2=Pin(25,Pin.IN)
SERVER = '你的服务器' # MQTT服务器
CLIENT_ID = ubinascii.hexlify(machine.unique_id()) # 获取ESP32的ID
SUBSCRIBE_TOPIC = b'你的订阅topic' # TOPIC的ID
username = '你的账号' # 账号，随便写
password = '你的密码' # 密码，随便写
PUBLISH_TOPIC = b'你的发送主题'
PHONE_TOPIC=b'' #手机主题，相当于红外线代替手机发了一个信息
def send_msg(msg):
client.publish(PUBLISH_TOPIC, msg)
def set_client():
global client
client = MQTTClient(CLIENT_ID, SERVER, 0, username, password, 60)
client.connect()
def connect_to_wifi():
wifi = network.WLAN(network.STA_IF) # 创建一个网络接口
if not wifi.isconnected():
wifi.active(True) # 激活网络接口
wifi.disconnect() # 中断之前连接的wifi
wifi.connect('你的网络账号', '你的网络密码') # 输入账号密码连接网络
while (wifi.ifconfig()[0] == '0.0.0.0'):
time.sleep(1)
print(wifi.ifconfig())
# infra_red_test()
from machine import UART,Pin
import utime
def init():
print('connecting to the infra_red')
connect_to_wifi()
set_client()
print('connecting completed')
client.publish('要发送到的主题','infra_red connected')
#check()
def send_to_net_infra_red_info():
while True:
if infra_red_receive.value()==0 and infra_red_receive2.value()==0:
send_msg('0')
print('forward and back all can')
elif infra_red_receive.value()==0 and infra_red_receive2.value()==1:
send_msg('1')
print('forward can , back not')
elif infra_red_receive.value()==1 and infra_red_receive2.value()==0:
send_msg('2')
print('forward not , back can')
#print('okBack')
elif infra_red_receive.value()==1 and infra_red_receive2.value()==1:
send_msg('3')
print('forward not, back not')
utime.sleep_ms(300)
init()
send_to_net_infra_red_info()
#infra_red_test()
本文章为转载内容，我们尊重原作者对文章享有的著作权。如有内容错误或侵权问题，欢迎原作者联系我们进行内容更正或删除文章。
