Need help Smart Car python programming

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1

Hi,
I am teacher in France and I need some help about programming robot in python.
I want to drive a robot “Smart Car” from Elecfreaks , via micropython (with mu editor).
It works fine with MakeCode blocks (with specific blocks for motorbit) but I can’t do it in python.

Here is my code in python :

from microbit import *

directD = pin8      # right dir (forward = 0, reverse = 1)
moteurD = pin1      # rigth motor (PWM)
directG = pin12     # left dir (forward = 0, reverse = 1)
moteurG = pin2      # left motor (PWM)

display.off         # désactivation des 25 leds

def avancer(vitesse):
    directD.write_digital(0)
    directG.write_digital(0)
    moteurD.write_analog(vitesse)
    moteurG.write_analog(vitesse)

def reculer(vitesse):
    directD.write_digital(1)
    directG.write_digital(1)
    moteurD.write_analog(1023-vitesse)
    moteurG.write_analog(1023-vitesse)

for k in range(2):
    avancer(1000)
    sleep(1000)
    reculer(1000)
    sleep(1000)

So what is wrong in this code ?

Thank you very much for your help

2

Hi @PatriceRabiller and welcome to the forum!

Does your robot move at all with this code or no? Do you have any errors in Python while running this script or no?

3

Yes it moves but instead of repeating twice “go forward + wait 1sec + go backward +wait for 1sec”
it does that : “move right + wait + move right + wait”

I verified the connection : the pins are correctly used. I did not weld the wires on the engines: I just pinched them. But this is probably not the problem because I was able to run the program written with the blocks :

EssaiMoteurSmartCar
EssaiMoteurSmartCar415×477 22.4 KB

4

Aaaaah I found the solution!
Looking for how the code for MakeCode was written, I found on github detailed export functions in JavaScript.

Here is my new code written in python:

from microbit import *

directD = pin8      # sens moteur D (avant = 0, arrière = 1)
moteurD = pin1      # moteur droit (PWM)
directG = pin12     # sens moteur G (avant = 1, arrière = 0)
moteurG = pin2      # moteur gauche (PWM)


def avancer(vitesse):
    directD.write_digital(0)
    directG.write_digital(1)
    moteurD.write_analog(vitesse)
    moteurG.write_analog(vitesse)

def reculer(vitesse):
    directD.write_digital(1)
    directG.write_digital(0)
    moteurD.write_analog(vitesse)
    moteurG.write_analog(vitesse)

for k in range(1):
    avancer(1000)
    sleep(1000)
    reculer(1000)
    sleep(1000)
    avancer(0)
5

great :slight_smile: