Get tutorials Raspberry Pi Sensor Kit V2.0 for Raspberry Pi B+

Lesson 32 MPU6050 Gyro Acceleration Sensor

 

Introduction

The MPU-6050 is the world’s first and only 6-axis motion tracking devices designed for the low power, low cost, and high performance requirements of smartphones, tablets and wearable sensors.


 


Components

- 1 * Raspberry Pi

- 1 * Breadboard

- 4 * Jumper wires (Male to Male, 2 red and 2 black)

- 1 * Network cable (or USB wireless network adapter)

- 1 * MPU-6050 module

- 4 * Jumper wires (M to F) (preferable to the 4-pin anti-reverse cable)

 

Experimental Principle

In this experiment, use I2C to obtain the values of the three-axis acceleration sensor and three-axis gyroscope for MPU6050 and display them on the screen.

 

Experimental Procedures

Step 1: Build the circuit


Raspberry Pi

T-Cobbler

MPU-6050 Module

SCL

SCL1

SCL

SDA

SDA1

SDA

5V

5V0

VCC

GND

GND

GND

 

Step2: Setup I2C (see Appendix 1. If you have set I2C, skip this step.)

For C language users:

Step 3: Change directory

cd /home/pi/SunFounder_SensorKit_for_RPi2/C/32_mpu6050/

Step 4: Compile

gcc 32_mpu6050_accel.c –lwiringPi –lm

gcc 32_mpu6050_gyro.c –lwiringPi –lm

Step 5: Run

sudo ./a.out

 

For Python users:

Step 3: Change directory

 cd /home/pi/SunFounder_SensorKit_for_RPi2/Python/

Step 4: Run

sudo python 32_mpu6050.py

 

Now you can see the values of the acceleration sensor, gyroscope, and XY-axis rotation read by MPU6050 printed on the screen constantly.

 

 

C Code

#include  <wiringPiI2C.h>
#include  <stdio.h>
#include  <math.h>

int fd;
int acclX, acclY, acclZ;
int gyroX, gyroY, gyroZ;
double acclX_scaled, acclY_scaled, acclZ_scaled;
double gyroX_scaled, gyroY_scaled, gyroZ_scaled;

int read_word_2c(int addr)
{
  int val;
  val = wiringPiI2CReadReg8(fd, addr);
  val = val << 8;
  val += wiringPiI2CReadReg8(fd, addr+1);
  if (val >= 0x8000)
    val = -(65536 - val);

  return val;
}

double dist(double a, double b)
{
  return sqrt((a*a) + (b*b));
}

double get_y_rotation(double x, double y, double z)
{
  double radians;
  radians = atan2(x, dist(y, z));
  return -(radians * (180.0 / M_PI));
}

double get_x_rotation(double x, double y, double z)
{
  double radians;
  radians = atan2(y, dist(x, z));
  return (radians * (180.0 / M_PI));
}

int main()
{
  fd = wiringPiI2CSetup (0x68);
  wiringPiI2CWriteReg8 (fd,0x6B,0x00);//disable sleep mode 
  printf("set 0x6B=%X\n",wiringPiI2CReadReg8 (fd,0x6B));
  
  while(1) {

    acclX = read_word_2c(0x3B);
    acclY = read_word_2c(0x3D);
    acclZ = read_word_2c(0x3F);

    acclX_scaled = acclX / 16384.0;
    acclY_scaled = acclY / 16384.0;
    acclZ_scaled = acclZ / 16384.0;
    
    printf("My acclX_scaled: %f\n", acclX_scaled);
    printf("My acclY_scaled: %f\n", acclY_scaled);
    printf("My acclZ_scaled: %f\n", acclZ_scaled);

    printf("My X rotation: %f\n", get_x_rotation(acclX_scaled, acclY_scaled, acclZ_scaled));
    printf("My Y rotation: %f\n", get_y_rotation(acclX_scaled, acclY_scaled, acclZ_scaled));

    
    delay(100);
  }
  return 0;
}





#include  <wiringPiI2C.h>
#include  <stdio.h>
#include  <math.h>

int fd;
int acclX, acclY, acclZ;
int gyroX, gyroY, gyroZ;
double acclX_scaled, acclY_scaled, acclZ_scaled;
double gyroX_scaled, gyroY_scaled, gyroZ_scaled;

int read_word_2c(int addr)
{
  int val;
  val = wiringPiI2CReadReg8(fd, addr);
  val = val << 8;
  val += wiringPiI2CReadReg8(fd, addr+1);
  if (val >= 0x8000)
    val = -(65536 - val);

  return val;
}

int main()
{
  fd = wiringPiI2CSetup (0x68);
  wiringPiI2CWriteReg8 (fd,0x6B,0x00);//disable sleep mode 
  printf("set 0x6B=%X\n",wiringPiI2CReadReg8 (fd,0x6B));
  
  while(1) {

    gyroX = read_word_2c(0x43);
    gyroY = read_word_2c(0x45);
    gyroZ = read_word_2c(0x47);

    gyroX_scaled = gyroX / 131.0;
    gyroY_scaled = gyroY / 131.0;
    gyroZ_scaled = gyroZ / 131.0;
    
    printf("My gyroX_scaled: %f\n", gyroX_scaled);
    printf("My gyroY_scaled: %f\n", gyroY_scaled);
    printf("My gyroZ_scaled: %f\n", gyroZ_scaled);

    
    delay(100);
  }
  return 0;
}


 

Python Code 

#!/usr/bin/python

import smbus
import math
import time

# Power management registers
power_mgmt_1 = 0x6b
power_mgmt_2 = 0x6c

def read_byte(adr):
    return bus.read_byte_data(address, adr)

def read_word(adr):
    high = bus.read_byte_data(address, adr)
    low = bus.read_byte_data(address, adr+1)
    val = (high << 8) + low
    return val

def read_word_2c(adr):
    val = read_word(adr)
    if (val >= 0x8000):
        return -((65535 - val) + 1)
    else:
        return val

def dist(a,b):
    return math.sqrt((a*a)+(b*b))

def get_y_rotation(x,y,z):
    radians = math.atan2(x, dist(y,z))
    return -math.degrees(radians)

def get_x_rotation(x,y,z):
    radians = math.atan2(y, dist(x,z))
    return math.degrees(radians)


bus = smbus.SMBus(1) # or bus = smbus.SMBus(1) for Revision 2 boards
address = 0x68       # This is the address value read via the i2cdetect command

# Now wake the 6050 up as it starts in sleep mode
bus.write_byte_data(address, power_mgmt_1, 0)

while True:
    time.sleep(0.1)
    gyro_xout = read_word_2c(0x43)
    gyro_yout = read_word_2c(0x45)
    gyro_zout = read_word_2c(0x47)

    print "gyro_xout : ", gyro_xout, " scaled: ", (gyro_xout / 131)
    print "gyro_yout : ", gyro_yout, " scaled: ", (gyro_yout / 131)
    print "gyro_zout : ", gyro_zout, " scaled: ", (gyro_zout / 131)

    accel_xout = read_word_2c(0x3b)
    accel_yout = read_word_2c(0x3d)
    accel_zout = read_word_2c(0x3f)

    accel_xout_scaled = accel_xout / 16384.0
    accel_yout_scaled = accel_yout / 16384.0
    accel_zout_scaled = accel_zout / 16384.0

    print "accel_xout: ", accel_xout, " scaled: ", accel_xout_scaled
    print "accel_yout: ", accel_yout, " scaled: ", accel_yout_scaled
    print "accel_zout: ", accel_zout, " scaled: ", accel_zout_scaled

    print "x rotation: " , get_x_rotation(accel_xout_scaled, accel_yout_scaled, accel_zout_scaled)
    print "y rotation: " , get_y_rotation(accel_xout_scaled, accel_yout_scaled, accel_zout_scaled)

    time.sleep(0.5)


 

 

 

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SunFounder
Apr 15 2017 at 05:56 am



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