I’ve tried matplotlib which has a very convenient polar coordinate mode, but the output looked very wrong, so there must be a few mistakes in here:
#!/usr/bin/python
import matplotlib.pyplot as plt
import matplotlib.animation as animation
import serial
import numpy as np
com_port = "/dev/ttyACM0"
baudrate = 115200
ser = serial.Serial(com_port, baudrate)
fig = plt.figure(figsize=(4,4))
ax = fig.add_subplot(111, projection='polar')
ax.set_ylim(0,2000)
data = np.zeros(360)
theta = np.linspace(0,360, num=360)
l, = ax.plot([],[])
databuffer = ""
def update(i):
global data, databuffer
if (ser.inWaiting()>0):
data_str = ser.read(ser.inWaiting()).decode('ascii')
databuffer += data_str
if ('A' in databuffer and 'B' in databuffer and 'C' in databuffer):
databuffer = databuffer.split('A')[1]
databuffer = databuffer.split('C')[0]
try:
(angle, distance) = databuffer.split('B')
ser.reset_input_buffer()
data[int(angle)]=int(distance)
except Exception as e: print(e)
l.set_data(theta, data )
return l,
ani = animation.FuncAnimation(fig, update, frames=360, interval=200, blit=True)
plt.show()
hello, very cool project! I’m currently trying to get a Xiaomi scanner on the Pi to work. How exactly did you do the wiring with the Pi? should the engine turn when connecting the 5V or do I have to do it myself?
Thanks for your Help…
The arduino program I have used took care of that by looking at the RPM and driving the motor via PWM
many thanks for the help. a question still should the laser led light up after I have connected 5V? if I connect my sensor to 5v, nothing happens.
The laser is controlled by the module internally. When the head is rotated (manually, with an unregulated DC motor or with the constant-speed PWM thingy) it automatically takes measurements and sends data
Oh yes, the laser diode is on after external motor start. Now I’ll check it out if data come out. If I connect GND and RX from the Raspberry with the sensor to test should Go?
Not sure if you will get useful data by making the connection between raspi and sensor directly. I had the arduino in between and I think it does some translation