All posts by admin

Servo Library for the Raspberry Pi Pico W in MicroPython

April 23, 2024 admin

In this lesson we demonstrate how to create a custom library on the Raspberry Pi Pico W to control a servo. We create a servo class, and then show how to use it as a library in future programs.

# ====================================================================
# DISCLAIMER:
# This code is provided as-is for educational and experimental 
# purposes only. The author makes no representations or warranties of 
# any kind concerning the safety, suitability, or accuracy of this 
# code. Use at your own risk. The author assumes no liability for any 
# damages, system failures, security breaches, or network issues 
# resulting from the use or implementation of this script.
# ====================================================================

class servo:
    def __init__(self,sPin):
        import machine
        self.servoPin=sPin
        self.obj=machine.PWM(machine.Pin(self.servoPin))
        self.obj.freq(50)
    
    def pos(self,angle):
        writeVal=6553/180*angle+1638
        self.obj.duty_u16(int(writeVal))

# ====================================================================

# DISCLAIMER:

# This code is provided as-is for educational and experimental

# purposes only. The author makes no representations or warranties of

# any kind concerning the safety, suitability, or accuracy of this

# code. Use at your own risk. The author assumes no liability for any

# damages, system failures, security breaches, or network issues

# resulting from the use or implementation of this script.

# ====================================================================

class servo:

def __init__(self,sPin):

import machine

self.servoPin=sPin

self.obj=machine.PWM(machine.Pin(self.servoPin))

self.obj.freq(50)

def pos(self,angle):

writeVal=6553/180*angle+1638

self.obj.duty_u16(int(writeVal))

MicroPython, Raspberry Pi Pico

How to Write Modular Code With Micropython Functions

March 19, 2024 admin

In this lesson we show how to write modular code in micropython. We demonstrate this with a simple example of how to calculate parameters of interest for a given rectangle. For your convenience, the code developed in the video is presented below. Enjoy!

def rectSolve(len,wid):
    #global area,perimeter,diagonal
    area=rectArea(len,wid)
    perimeter=rectPerimeter(len,wid)
    diagonal=rectDiagonal(len,wid)
    return area,perimeter,diagonal

def rectArea(len,wid):
    area=len*wid
    return area

def rectPerimeter(len,wid):
    perimeter=2*len+2*wid
    return perimeter

def rectDiagonal(len,wid):
    diag=(len**2+wid**2)**(1/2)
    return diag
   
while True:
    l=float(input("What is Length of your Rectangle? "))
    w=float(input("what is the Width of your Rectuangle? "))
    a,p,d = rectSolve(l,w)
    print("Your Rectangle Information: ")
    print("Area: ",a)
    print("Perimeter: ",p)
    print("Diagonal: ",d)
    print()

def rectSolve(len,wid):

#global area,perimeter,diagonal

area=rectArea(len,wid)

perimeter=rectPerimeter(len,wid)

diagonal=rectDiagonal(len,wid)

return area,perimeter,diagonal

def rectArea(len,wid):

area=len*wid

return area

def rectPerimeter(len,wid):

perimeter=2*len+2*wid

return perimeter

def rectDiagonal(len,wid):

diag=(len**2+wid**2)**(1/2)

return diag

while True:

l=float(input("What is Length of your Rectangle? "))

w=float(input("what is the Width of your Rectuangle? "))

a,p,d = rectSolve(l,w)

print("Your Rectangle Information: ")

print("Area: ",a)

print("Perimeter: ",p)

print("Diagonal: ",d)

print()

MicroPython, Raspberry Pi Pico

Calibrating Joystick to Show Positional Angle in MicroPython on the Raspberry Pi Pico W

March 5, 2024 admin

In this Video Lesson we show how to calibrate a joystick to report Angular Position. We do this using MicroPython on a Raspberry Pi Pico W. For your convenience, the code is included below.

# ====================================================================
# DISCLAIMER:
# This code is provided as-is for educational and experimental 
# purposes only. The author makes no representations or warranties of 
# any kind concerning the safety, suitability, or accuracy of this 
# code. Use at your own risk. The author assumes no liability for any 
# damages, system failures, security breaches, or network issues 
# resulting from the use or implementation of this script.
# ====================================================================

import machine
import time
import math
hPin=27
vPin=26
hJoy= machine.ADC(hPin)
vJoy= machine.ADC(vPin)
while True:
    hVal=hJoy.read_u16()
    vVal=vJoy.read_u16()
    
    hCal=int(-.00306*hVal+100.766)
    vCal=int(.00306*vVal-100.766)
    
    deg=math.atan2(vCal,hCal)*360/2/math.pi
    if hCal==0:
        hCal=1
    if deg<0:
        deg=deg+360
    
    mag=math.sqrt(hCal**2+vCal**2)
    if mag<=4:
        hCal=0
        vCal=0
    
    print(hCal,vCal,deg)
    time.sleep_ms(200)

# ====================================================================

# DISCLAIMER:

# This code is provided as-is for educational and experimental

# purposes only. The author makes no representations or warranties of

# any kind concerning the safety, suitability, or accuracy of this

# code. Use at your own risk. The author assumes no liability for any

# damages, system failures, security breaches, or network issues

# resulting from the use or implementation of this script.

# ====================================================================

import machine

import time

import math

hPin=27

vPin=26

hJoy= machine.ADC(hPin)

vJoy= machine.ADC(vPin)

while True:

hVal=hJoy.read_u16()

vVal=vJoy.read_u16()

hCal=int(-.00306*hVal+100.766)

vCal=int(.00306*vVal-100.766)

deg=math.atan2(vCal,hCal)*360/2/math.pi

if hCal==0:

hCal=1

if deg<0:

deg=deg+360

mag=math.sqrt(hCal**2+vCal**2)

if mag<=4:

hCal=0

vCal=0

print(hCal,vCal,deg)

time.sleep_ms(200)

Uncategorized

Calibrating a Joystick on the Raspberry Pi Pico W in MicroPython

February 27, 2024 admin

In this lesson we show how to get intuitive calibrated results from a joystick, connected to a Raspberry Pi Pico W, using microPython. This lesson will make it easy to incorporate a joystick into Pico W projects.

For your convenience, the code we develop in the video above is included below.

# ====================================================================
# DISCLAIMER:
# This code is provided as-is for educational and experimental 
# purposes only. The author makes no representations or warranties of 
# any kind concerning the safety, suitability, or accuracy of this 
# code. Use at your own risk. The author assumes no liability for any 
# damages, system failures, security breaches, or network issues 
# resulting from the use or implementation of this script.
# ====================================================================

import machine
import time
import math
hPin=27
vPin=26
hJoy= machine.ADC(hPin)
vJoy= machine.ADC(vPin)
while True:
    hVal=hJoy.read_u16()
    vVal=vJoy.read_u16()
    
    hCal=int(-.00306*hVal+100.766)
    vCal=int(.00306*vVal-100.766)
    
    mag=math.sqrt(hCal**2+vCal**2)
    if mag<=4:
        hCal=0
        vCal=0
    
    print(hCal,vCal)
    time.sleep_ms(200)

# ====================================================================

# DISCLAIMER:

# This code is provided as-is for educational and experimental

# purposes only. The author makes no representations or warranties of

# any kind concerning the safety, suitability, or accuracy of this

# code. Use at your own risk. The author assumes no liability for any

# damages, system failures, security breaches, or network issues

# resulting from the use or implementation of this script.

# ====================================================================

import machine

import time

import math

hPin=27

vPin=26

hJoy= machine.ADC(hPin)

vJoy= machine.ADC(vPin)

while True:

hVal=hJoy.read_u16()

vVal=vJoy.read_u16()

hCal=int(-.00306*hVal+100.766)

vCal=int(.00306*vVal-100.766)

mag=math.sqrt(hCal**2+vCal**2)

if mag<=4:

hCal=0

vCal=0

print(hCal,vCal)

time.sleep_ms(200)

MicroPython, Raspberry Pi Pico

Remove Long Term Steady State Errors from MPU6050 Tilt Measurements

January 2, 2024 admin

In this video lesson I show you how to remove long term steady state error from the tilt values calculated from the MPU6050 IMU. We are using the following schematic for our prototype.

For your convenience, this is the code we developed in the video.

# ====================================================================
# DISCLAIMER:
# This code is provided as-is for educational and experimental 
# purposes only. The author makes no representations or warranties of 
# any kind concerning the safety, suitability, or accuracy of this 
# code. Use at your own risk. The author assumes no liability for any 
# damages, system failures, security breaches, or network issues 
# resulting from the use or implementation of this script.
# ====================================================================

from imu import MPU6050
from machine import I2C,Pin
import math
import time
 
i2c=I2C(0, sda=Pin(16), scl=Pin(17), freq=400000)
mpu = MPU6050(i2c)
 
rollG=0
pitchG=0

rollComp=0
pitchComp=0

errorR=0
errorP=0

yaw=0
tLoop=0
cnt=0
 
while True:
    tStart=time.ticks_ms()
    
    xGyro=mpu.gyro.x
    yGyro=-mpu.gyro.y
    zGyro=mpu.gyro.z
    
    xAccel=mpu.accel.x
    yAccel=mpu.accel.y
    zAccel=mpu.accel.z
    
    rollG=rollG+yGyro*tLoop
    pitchG=pitchG+xGyro*tLoop
    
    rollA=math.atan(xAccel/zAccel)/2/math.pi*360
    pitchA=math.atan(yAccel/zAccel)/2/math.pi*360
    
    rollComp= rollA*.005 + .995*(rollComp+yGyro*tLoop)+errorR*.005
    pitchComp= pitchA*.005 + .995*(pitchComp+xGyro*tLoop)+errorP*.005
    
    errorP=errorP + (pitchA-pitchComp)*tLoop
    errorR=errorR + (rollA-rollComp)*tLoop
    
    cnt=cnt+1
    if cnt==10:
        cnt=0
        print('RA: ',rollA,'PA: ',pitchA,'RC: ',rollComp,'PC: ',pitchComp)
        #print('RA: ',rollA,'RC: ',rollComp)
    tStop=time.ticks_ms()
    tLoop=(tStop-tStart)*.001

# ====================================================================

# DISCLAIMER:

# This code is provided as-is for educational and experimental

# purposes only. The author makes no representations or warranties of

# any kind concerning the safety, suitability, or accuracy of this

# code. Use at your own risk. The author assumes no liability for any

# damages, system failures, security breaches, or network issues

# resulting from the use or implementation of this script.

# ====================================================================

from imu import MPU6050

from machine import I2C,Pin

import math

import time

i2c=I2C(0, sda=Pin(16), scl=Pin(17), freq=400000)

mpu = MPU6050(i2c)

rollG=0

pitchG=0

rollComp=0

pitchComp=0

errorR=0

errorP=0

yaw=0

tLoop=0

cnt=0

while True:

tStart=time.ticks_ms()

xGyro=mpu.gyro.x

yGyro=-mpu.gyro.y

zGyro=mpu.gyro.z

xAccel=mpu.accel.x

yAccel=mpu.accel.y

zAccel=mpu.accel.z

rollG=rollG+yGyro*tLoop

pitchG=pitchG+xGyro*tLoop

rollA=math.atan(xAccel/zAccel)/2/math.pi*360

pitchA=math.atan(yAccel/zAccel)/2/math.pi*360

rollComp= rollA*.005 + .995*(rollComp+yGyro*tLoop)+errorR*.005

pitchComp= pitchA*.005 + .995*(pitchComp+xGyro*tLoop)+errorP*.005

errorP=errorP + (pitchA-pitchComp)*tLoop

errorR=errorR + (rollA-rollComp)*tLoop

cnt=cnt+1

if cnt==10:

cnt=0

print('RA: ',rollA,'PA: ',pitchA,'RC: ',rollComp,'PC: ',pitchComp)

#print('RA: ',rollA,'RC: ',rollComp)

tStop=time.ticks_ms()

tLoop=(tStop-tStart)*.001

Technology Tutorials

All posts by admin

Servo Library for the Raspberry Pi Pico W in MicroPython

How to Write Modular Code With Micropython Functions

Calibrating Joystick to Show Positional Angle in MicroPython on the Raspberry Pi Pico W

Calibrating a Joystick on the Raspberry Pi Pico W in MicroPython

Remove Long Term Steady State Errors from MPU6050 Tilt Measurements

Making The World a Better Place One High Tech Project at a Time. Enjoy!