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MRPi1 – Wake up alarm

Wake up alarm with MRPi1 robot. The robot stops the alarm automaticly when the robot detects the light.

Python program :

# import mrpi1 lib
from mrpi1_lib import *
import time


  while 1:
    al1 = ambiantLight(1) # read ambiant light,sensor 1
    al2 = ambiantLight(2)
    al3 = ambiantLight(3)
    al4 = ambiantLight(4)
    al5 = ambiantLight(5)
    al6 = ambiantLight(6)
    print "Ambiant light = %d %d %d %d %d %d" %(al1, al2, al3, al4, al5, al6)

    if (al1 < 4000 and al2 < 4000): # light detects
     print "end alarm"
     writeCommand("SPD")# disable speaker
      playWav("alarmClock.wav") # play alarm wav file

  writeCommand("SPD") # disable speaker


PID control

In this video MRPi1 robot is controled by two PID controller. The PID controller calculates an error values between motors encoders and desired value (orientation and distance).

  • Orientation control
  • Distance control

The speed profile :

  • Trapezoid profile with 3 parts : acceleration, constant speed and deceleration.

Encoders specification :

  • Magnetic encoder,
  • Resolution : 12 ticks/tr

Raspberry Pi robot – MRPi1 from macerobotics on Vimeo.