MPU6050_basic

About:

A MPU6050 driver I wrote that only reads sensor data from the MPU, for arduino nano , used for a Line Follower. My team only needed Gyroscope and Accelerometer Readings for the project, and most libraries were too big to fit all the project, So I wrote this library myself.

IMPORTANT: I Haven't tested this Library yet for the Accelerometer

In this file, I will explain how to get started to use this library for your projects.

Functions summary:

This is a quick summary for the functions that can be used in this Library for quick refrencing. Details are explained later below.

#define gyroMode pm1000
//modes --> {pm250, pm500, pm1000, pm2000}
#define accelMode pm4
//modes --> {pm2, pm4, pm8, pm16}
void mpu_init();    //Reset the MPU and reconfigure Accelerometer and Gyroscope Ranges. Must be used after the two lines above.

//Getting Reading from Gyroscope in [deg/sec]
float gyro_read_x();
float gyro_read_y();
float gyro_read_z();
//Getting Angle Reading from gyroscope by integration over time.
float readAngle(char axes,bool reset);

//Getting Accelerometer readings.
float accel_read_x();
float accel_read_y();
float accel_read_z();
float readVelocity(char axes, bool reset);
float readPosition(char axes, bool reset);

MPU Initialization.

The MPU6050 communicates using the IIC protocol, It has a 7-bit address = 0x68 or 0x69 depending on the input on A0 pin in the IC, which is considered the first bit in the MPU adress.

The function mpu_init() automatically sets the Arduino as a master, resets the MPU and configure the gyroscope and accelerometer ranges.

To properly initialize your MPU6050, you should write your code something like this:

#include <MPU6050_basic.h>
//-----other libraties and stuff-----
#define gyroMode    pm1000 //or any other value, will explain later.
#define accelMode   pm8

void setup()
{
    mpu_init();
 //-----------------------rest of the code------------------------

As seen above, gyroMode and accelMode should be defined before calling the function mpu_init()

Gyroscope Ranges:

The Gyroscope in MPU6050 has four ranges shown in the below table:

Range(deg/sec)	#define parameter
±250	pm250
±500	pm500
±1000	pm1000
±2000	pm2000

These mode refer to the highest and lowest change they can sense.

In my experience, The higher the range, the lower the error in readAngle() function. You should choose the higher possible value, depending on the accuracy you need in your project.

Accelerometer Ranges:

The Accelerometer also have four ranges you can choose from, As shown in the table below:

Range(9.81 m/s^2)	#define parameter
±2	pm2
±4	pm4
±8	pm8
±16	pm16

Taking Readings

Gyroscope

To get Reading from the MPU6050, you must initialise it as shown above. After initialization, The following Functions return a floating point value in Deg/sec

gyro_read_x();
gyro_read_y();
gyro_read_z();

To get the Angle reading, Normally you will integrate the returned values from the previous three functions to get roll('x'), pitch('y') and yaw ('z') respectively, but I added a function that basically does that:

angX = readAngle('x',false);

The first run of this function should return a zero. Then the output will change depending on your angle and the noise and inaccuracies in time measurements (which its significance largely dependent in gyroMode).

It's preferred to run this function in a loop to get accurate readings. and If you want to reset the reading, you should changing false to true, but it's recomennded to be outside of an infinite loop or the value will be nearly always equal to zero.

IMPORTANT NOTE: The functions for Angle, Velocity and Position are using the same integration function, which includes a static variable.This where resert variable comes into play. If you wanted to get multiple reading other than a single one, other than the basic gyroscope and acceleration readings, you have to do it like this:

float Vx, Vy, Vz;

void setup()
{
    mpu_init();
    Vx = 0;
    Vy = 0;
    Vz = 0;
}

void loop()
{
    Vx += readVelocity('x', true);
    Vy += readVelocity('y', true);
    Vz += readVelocity('z', true);
}

Accelerometer

Its reading is the same as the gyroscope. and the functions are the following: The returned values are in meters/second^2

accel_read_x();
accel_read_y();
accel_read_z();

The Velocity and Acceleration can be calculated using those two functions:

float readVelocity(char axes, bool reset);
float readPosition(char axes, bool reset);

And the logic to use it is the same as I told in the gyroscope example.

Feedback and notices:

This is my first ever driver I wrote by solely relying on the manufacturer datasheets, and I don't have the module, So I don't have a lot of chances to test my code on actual hardware. Please be free to test my code and report any issues you may encounter to me and I'll try to fix it. or you can contribute to it, but I need this library to be as small as possible for the essential stuff.