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[BBAir] [활용기] IMU(MPU6050) 값 읽어오기(raw data) : I2C를 활용한

[BBAir] [활용기] IMU(MPU6050) 값 읽어오기(raw data) : I2C를 활용한

"" "This program handles the communication over I2C

between a Raspberry Pi and a MPU-6050 Gyroscope / Accelerometer combo.

Made by: MrTijn/Tijndagamer

Released under the MIT License

Copyright 2015

" ""

import smbus

from time import sleep

class MPU6050:

# Global Variables

GRAVITIY_MS2 = 9. 80665

address = None

bus = smbus.SMBus( 1 )

# Scale Modifiers

ACCEL_SCALE_MODIFIER_2G = 16384. 0

ACCEL_SCALE_MODIFIER_4G = 8192. 0

ACCEL_SCALE_MODIFIER_8G = 4096. 0

ACCEL_SCALE_MODIFIER_16G = 2048. 0

GYRO_SCALE_MODIFIER_250DEG = 131. 0

GYRO_SCALE_MODIFIER_500DEG = 65. 5

GYRO_SCALE_MODIFIER_1000DEG = 32. 8

GYRO_SCALE_MODIFIER_2000DEG = 16. 4

# Pre-defined ranges

ACCEL_RANGE_2G = 0x00

ACCEL_RANGE_4G = 0x08

ACCEL_RANGE_8G = 0x10

ACCEL_RANGE_16G = 0x18

GYRO_RANGE_250DEG = 0x00

GYRO_RANGE_500DEG = 0x08

GYRO_RANGE_1000DEG = 0x10

GYRO_RANGE_2000DEG = 0x18

# MPU-6050 Registers

PWR_MGMT_1 = 0x6B

PWR_MGMT_2 = 0x6C

SELF_TEST_X = 0x0D

SELF_TEST_Y = 0x0E

SELF_TEST_Z = 0x0F

SELF_TEST_A = 0x10

ACCEL_XOUT0 = 0x3B

ACCEL_XOUT1 = 0x3C

ACCEL_YOUT0 = 0x3D

ACCEL_YOUT1 = 0x3E

ACCEL_ZOUT0 = 0x3F

ACCEL_ZOUT1 = 0x40

TEMP_OUT0 = 0x41

TEMP_OUT1 = 0x42

GYRO_XOUT0 = 0x43

GYRO_XOUT1 = 0x44

GYRO_YOUT0 = 0x45

GYRO_YOUT1 = 0x46

GYRO_ZOUT0 = 0x47

GYRO_ZOUT1 = 0x48

ACCEL_CONFIG = 0x1C

GYRO_CONFIG = 0x1B

def __init__(self, address):

self.address = address

# Wake up the MPU-6050 since it starts in sleep mode

self.bus.write_byte_data(self.address, self.PWR_MGMT_1, 0x00 )

# I2C communication methods

def read_i2c_word(self, register):

"" "Read two i2c registers and combine them.

register -- the first register to read from.

Returns the combined read results.

" ""

# Read the data from the registers

high = self.bus.read_byte_data(self.address, register)

low = self.bus.read_byte_data(self.address, register + 1 )

value = (high < < 8 ) + low

if (value > = 0x8000 ):

return - (( 65535 - value) + 1 )

else :

return value

# MPU-6050 Methods

def get_temp(self):

"" "Reads the temperature from the onboard temperature sensor of the MPU-6050.

Returns the temperature in degrees Celcius.

" ""

# Get the raw data

raw_temp = self.read_i2c_word(self.TEMP_OUT0)

# Get the actual temperature using the formule given in the

# MPU-6050 Register Map and Descriptions revision 4.2, page 30

actual_temp = (raw_temp / 340 ) + 36. 53

# Return the temperature

return actual_temp

def set_accel_range(self, accel_range):

"" "Sets the range of the accelerometer to range.

accel_range -- the range to set the accelerometer to. Using a

pre-defined range is advised.

" ""

# First change it to 0x00 to make sure we write the correct value later

self.bus.write_byte_data(self.address, self.ACCEL_CONFIG, 0x00 )

# Write the new range to the ACCEL_CONFIG register

self.bus.write_byte_data(self.address, self.ACCEL_CONFIG, accel_range)

def read_accel_range(self, raw = False):

"" "Reads the range the accelerometer is set to.

If raw is True, it will return the raw value from the ACCEL_CONFIG

register

If raw is False, it will return an integer: -1, 2, 4, 8 or 16. When it

returns -1 something went wrong.

" ""

# Get the raw value

raw_data = self.bus.read_byte_data(self.address, self.ACCEL_CONFIG)

if raw is True:

return raw_data

elif raw is False:

if raw_data = = self.ACCEL_RANGE_2G:

return 2

elif raw_data = = self.ACCEL_RANGE_4G:

return 4

elif raw_data = = self.ACCEL_RANGE_8G:

return 8

elif raw_data = = self.ACCEL_RANGE_16G:

return 16

else :

return - 1

def get_accel_data(self, g = False):

"" "Gets and returns the X, Y and Z values from the accelerometer.

If g is True, it will return the data in g

If g is False, it will return the data in m/s^2

Returns a dictionary with the measurement results.

" ""

# Read the data from the MPU-6050

x = self.read_i2c_word(self.ACCEL_XOUT0)

y = self.read_i2c_word(self.ACCEL_YOUT0)

z = self.read_i2c_word(self.ACCEL_ZOUT0)

accel_scale_modifier = None

accel_range = self.read_accel_range(True)

if accel_range = = self.ACCEL_RANGE_2G:

accel_scale_modifier = self.ACCEL_SCALE_MODIFIER_2G

elif accel_range = = self.ACCEL_RANGE_4G:

accel_scale_modifier = self.ACCEL_SCALE_MODIFIER_4G

elif accel_range = = self.ACCEL_RANGE_8G:

accel_scale_modifier = self.ACCEL_SCALE_MODIFIER_8G

elif accel_range = = self.ACCEL_RANGE_16G:

accel_scale_modifier = self.ACCEL_SCALE_MODIFIER_16G

else :

print ( "Unkown range - accel_scale_modifier set to self.ACCEL_SCALE_MODIFIER_2G" )

accel_scale_modifier = self.ACCEL_SCALE_MODIFIER_2G

x = x / accel_scale_modifier

y = y / accel_scale_modifier

z = z / accel_scale_modifier

if g is True:

return { 'x' : x, 'y' : y, 'z' : z}

elif g is False:

x = x * self.GRAVITIY_MS2

y = y * self.GRAVITIY_MS2

z = z * self.GRAVITIY_MS2

return { 'x' : x, 'y' : y, 'z' : z}

def set_gyro_range(self, gyro_range):

"" "Sets the range of the gyroscope to range.

gyro_range -- the range to set the gyroscope to. Using a pre-defined

range is advised.

" ""

# First change it to 0x00 to make sure we write the correct value later

self.bus.write_byte_data(self.address, self.GYRO_CONFIG, 0x00 )

# Write the new range to the ACCEL_CONFIG register

self.bus.write_byte_data(self.address, self.GYRO_CONFIG, gyro_range)

def read_gyro_range(self, raw = False):

"" "Reads the range the gyroscope is set to.

If raw is True, it will return the raw value from the GYRO_CONFIG

register.

If raw is False, it will return 250, 500, 1000, 2000 or -1. If the

returned value is equal to -1 something went wrong.

" ""

# Get the raw value

raw_data = self.bus.read_byte_data(self.address, self.GYRO_CONFIG)

if raw is True:

return raw_data

elif raw is False:

if raw_data = = self.GYRO_RANGE_250DEG:

return 250

elif raw_data = = self.GYRO_RANGE_500DEG:

return 500

elif raw_data = = self.GYRO_RANGE_1000DEG:

return 1000

elif raw_data = = self.GYRO_RANGE_2000DEG:

return 2000

else :

return - 1

def get_gyro_data(self):

"" "Gets and returns the X, Y and Z values from the gyroscope.

Returns the read values in a dictionary.

" ""

# Read the raw data from the MPU-6050

x = self.read_i2c_word(self.GYRO_XOUT0)

y = self.read_i2c_word(self.GYRO_YOUT0)

z = self.read_i2c_word(self.GYRO_ZOUT0)

gyro_scale_modifier = None

gyro_range = self.read_gyro_range(True)

if gyro_range = = self.GYRO_RANGE_250DEG:

gyro_scale_modifier = self.GYRO_SCALE_MODIFIER_250DEG

elif gyro_range = = self.GYRO_RANGE_500DEG:

gyro_scale_modifier = self.GYRO_SCALE_MODIFIER_500DEG

elif gyro_range = = self.GYRO_RANGE_1000DEG:

gyro_scale_modifier = self.GYRO_SCALE_MODIFIER_1000DEG

elif gyro_range = = self.GYRO_RANGE_2000DEG:

gyro_scale_modifier = self.GYRO_SCALE_MODIFIER_2000DEG

else :

print ( "Unkown range - gyro_scale_modifier set to self.GYRO_SCALE_MODIFIER_250DEG" )

gyro_scale_modifier = self.GYRO_SCALE_MODIFIER_250DEG

x = x / gyro_scale_modifier

y = y / gyro_scale_modifier

z = z / gyro_scale_modifier

return { 'x' : x, 'y' : y, 'z' : z}

def get_all_data(self):

"" "Reads and returns all the available data." ""

temp = get_temp()

accel = get_accel_data()

gyro = get_gyro_data()

return [accel, gyro, temp]

# Create a new instance of the MPU6050 class

sensor = MPU6050( 0x68 )

while True:

accel_data = sensor.get_accel_data()

gyro_data = sensor.get_gyro_data()

temp = sensor.get_temp()

print ( "Accelerometer data" )

print ( "x: " + str (accel_data[ 'x' ]))

print ( "y: " + str (accel_data[ 'y' ]))

print ( "z: " + str (accel_data[ 'z' ]))

print ( "Gyroscope data" )

print ( "x: " + str (gyro_data[ 'x' ]))

print ( "y: " + str (gyro_data[ 'y' ]))

print ( "z: " + str (gyro_data[ 'z' ]))

print ( "" )

from http://openmaker.tistory.com/42 by ccl(S) rewrite - 2020-03-06 09:54:35

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