I am currently working on a quadcopter project whichthat involves IMUan MPU6050 accelerometer+gyroscope module, an ultrasonic sensor and control of electronic speed controllers. I have used existing examples and modified them to get raw values of acceleration, yaw pitch and roll angles, and the distance from the ultrasonic. Here is the long code.
#include "I2Cdev.h"
#include "MPU6050_6Axis_MotionApps20.h"
//#include "MPU6050.h" // not necessary if using MotionApps include file
#if I2CDEV_IMPLEMENTATION == I2CDEV_ARDUINO_WIRE
#include "Wire.h"
#endif
MPU6050 mpu;
//MPU6050 mpu(0x69); // <-- use for AD0 high
const int trigPin = 9;
const int echoPin = 10;
#define INTERRUPT_PIN 2 // use pin 2 on Arduino Uno & most boards
#define LED_PIN 13 // (Arduino is 13, Teensy is 11, Teensy++ is 6)
bool blinkState = false;
// MPU control/status vars
bool dmpReady = false; // set true if DMP init was successful
uint8_t mpuIntStatus; // holds actual interrupt status byte from MPU
uint8_t devStatus;
uint16_t packetSize; // expected DMP packet size (default is 42 bytes)
uint16_t fifoCount; // count of all bytes currently in FIFO
uint8_t fifoBuffer[64]; // FIFO storage buffer
// orientation/motion vars
Quaternion q; // [w, x, y, z] quaternion container
VectorInt16 aa; // [x, y, z] accel sensor measurements
VectorInt16 aaReal; // [x, y, z]gravity-free accel sensor measurements
VectorInt16 aaWorld; // [x, y, z] world-frame accel sensor measurements
VectorFloat gravity; // [x, y, z] gravity vector
float euler[3]; // [psi, theta, phi] Euler angle container
float ypr[3], yprd[3] = {0, 0, 0};
// packet structure for InvenSense teapot demo
uint8_t teapotPacket[14]=teapotPacket[14] = {'$', 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0x00, 0x00, '\r', '\n' };
// ================================================================
// === INTERRUPT DETECTION ROUTINE ===
// ================================================================
volatile bool mpuInterrupt = false;
void dmpDataReady() {
mpuInterrupt = true;
}
// ================================================================
// === INITIAL SETUP ===
// ================================================================
int16_t yo = 0, po = 0, ro = 0;
int lv=lv = 1, flag = 0;
const int MPU_addr=0x68;MPU_addr = 0x68; // I2C address of the MPU-6050
int16_t AcX, AcY, AcZ, Tmp, GyX, GyY, GyZ;
int32_t AcXo=0AcXo = 0,AcYo=0 AcYo = 0,AcZo=0 AcZo = 0, prev, curr;
int32_t AcXd=0AcXd = 0,AcYd=0 AcYd = 0,AcZd=0; AcZd = 0;
int i = 1, flaggl = 0;
int glc = 0, lv2 = 1;
long duration;
int distance, distanced;
void setup() {
#if I2CDEV_IMPLEMENTATION == I2CDEV_ARDUINO_WIRE
Wire.begin();
Wire.setClock(400000);
#elif I2CDEV_IMPLEMENTATION == I2CDEV_BUILTIN_FASTWIRE
Fastwire::setup(400, true);
#endif
Serial.begin(115200);
// initialize device
Serial.println(F("Initializing I2C devices..."));
mpu.initialize();
pinMode(INTERRUPT_PIN, INPUT);
// verify connection
Serial.println(F("Testing device connections..."));
Serial.println(mpu.testConnection() ? F("MPU6050 connection successful") :
F("MPU6050 connection failed"));
// wait for ready
Serial.println(F("\nSend any character to begin DMP programming and demo:
"));
while (Serial.available() && Serial.read()); // empty buffer
while (!Serial.available()); // wait for data
while (Serial.available() && Serial.read()); // empty buffer again
// load and configure the DMP
Serial.println(F("Initializing DMP..."));
devStatus = mpu.dmpInitialize();
// supply your own gyro offsets here, scaled for min sensitivity
mpu.setXGyroOffset(220);
mpu.setYGyroOffset(76);
mpu.setZGyroOffset(-85);
mpu.setZAccelOffset(1788); // 1688 factory default for my test chip
// make sure it worked (returns 0 if so)
if (devStatus == 0) {
// turn on the DMP, now that it's ready
Serial.println(F("Enabling DMP..."));
mpu.setDMPEnabled(true);
// enable Arduino interrupt detection
Serial.println(F("Enabling interrupt detection (Arduino external
interrupt 0)..."));
attachInterrupt(digitalPinToInterrupt(INTERRUPT_PIN), dmpDataReady, RISING);
mpuIntStatus = mpu.getIntStatus();
// set our DMP Ready flag so the main loop() function knows it's okay to use it
Serial.println(F("DMP ready! Waiting for first interrupt..."));
dmpReady = true;
// get expected DMP packet size for later comparison
packetSize = mpu.dmpGetFIFOPacketSize();
} else {
// ERROR!
// 1 = initial memory load failed
// 2 = DMP configuration updates failed
// (if it's going to break, usually the code will be 1)
Serial.print(F("DMP Initialization failed (code "));
Serial.print(devStatus);
Serial.println(F(")"));
}
// configure LED for output
pinMode(LED_PIN, OUTPUT);
/*Wire.begin();
Wire.beginTransmission(MPU_addr);
Wire.write(0x6B); // PWR_MGMT_1 register
Wire.write(0); // set to zero (wakes up the MPU-6050)
Wire.endTransmission(true);
Serial.begin(9600);
Serial.println("executing setup");*/
glc = 0;
distance = distanced = 0;
}
// ================================================================
// === MAIN PROGRAM LOOP ===
// ================================================================
void loop() {
// if programming failed, don't try to do anything
if (!dmpReady) return;
// wait for MPU interrupt or extra packet(s) available
while (!mpuInterrupt && fifoCount < packetSize) {
}
mpuInterrupt = false;
mpuIntStatus = mpu.getIntStatus();
// get current FIFO count
fifoCount = mpu.getFIFOCount();
// wait for MPU interrupt or extra packet(s) available
while (!mpuInterrupt && fifoCount < packetSize) {
}
mpuInterrupt = false;
mpuIntStatus = mpu.getIntStatus();
// get current FIFO count
fifoCount = mpu.getFIFOCount();
// check for overflow (this should never happen unless our code is too inefficient)
if ((mpuIntStatus & 0x10) || fifoCount == 1024) {
// reset so we can continue cleanly
mpu.resetFIFO();
Serial.println(F("FIFO overflow!"));
// otherwise, check for DMP data ready interrupt (this should happen frequently)
} else if (mpuIntStatus & 0x02) {
// wait for correct available data length, should be a VERY short wait
while (fifoCount < packetSize) fifoCount = mpu.getFIFOCount();
// read a packet from FIFO
mpu.getFIFOBytes(fifoBuffer, packetSize);
// track FIFO count here in case there is > 1 packet available
// (this lets us immediately read more without waiting for an interrupt)
fifoCount -= packetSize;
//#ifdef OUTPUT_READABLE_YAWPITCHROLL
// display Euler angles in degrees
mpu.dmpGetQuaternion(&q, fifoBuffer);
mpu.dmpGetGravity(&gravity, &q);
mpu.dmpGetYawPitchRoll(ypr, &q, &gravity);
if (millis() > 30000 && flag ==0== 0) {
if ( flag == 0 && lv < 21)
{
yo += ypr[0] * 180 / M_PI;
po += ypr[1] * 180 / M_PI;
ro += ypr[2] * 180 / M_PI;
++lv;
}
else if (flag == 0)
{
flag = 1;
yo /= 20;
po /= 20;
ro /= 20;
}
}
//#endif
// blink LED to indicate activity
blinkState = !blinkState;
digitalWrite(LED_PIN, blinkState);
Wire.beginTransmission(MPU_addr);
Wire.write(0x3B); // starting with register 0x3B (ACCEL_XOUT_H)
Wire.endTransmission(false);
Wire.requestFrom(MPU_addr, 14, true); // request a total of 14 registers
AcX=Wire AcX = Wire.read()<<8|Wire << 8 | Wire.read(); // 0x3B (ACCEL_XOUT_H) & 0x3C (ACCEL_XOUT_L)
AcY
AcY=Wire= Wire.read()<<8|Wire << 8 | Wire.read(); // 0x3D (ACCEL_YOUT_H) & 0x3E (ACCEL_YOUT_L)
AcZ=Wire AcZ = Wire.read()<<8|Wire << 8 | Wire.read(); // 0x3F (ACCEL_ZOUT_H) & 0x40 (ACCEL_ZOUT_L)
Tmp=Wire Tmp = Wire.read()<<8|Wire << 8 | Wire.read(); // 0x41 (TEMP_OUT_H) & 0x42 (TEMP_OUT_L)
GyX=Wire GyX = Wire.read()<<8|Wire << 8 | Wire.read(); // 0x43 (GYRO_XOUT_H) & 0x44 (GYRO_XOUT_L)
GyY=Wire GyY = Wire.read()<<8|Wire << 8 | Wire.read(); // 0x45 (GYRO_YOUT_H) & 0x46 (GYRO_YOUT_L)
GyZ=Wire GyZ = Wire.read()<<8|Wire << 8 | Wire.read(); // 0x47 (GYRO_ZOUT_H) & 0x48 (GYRO_ZOUT_L)
mpu.resetFIFO();
if (i < 21 && !flaggl)
{
AcXo += AcX;
AcYo += AcY;
AcZo += AcZ;
/*GyXo += GyX;
GyYo += GyY;
GyZo += GyZ;*/
++i;
Serial.println();
Serial.println("***************************************************************************");
}
else if (!flaggl)
{
flaggl = 1;
AcXo = AcXo / 20;
AcYo = AcYo / 20;
AcZo = AcZo/20;
/*GyXo = GyXoAcZo / 20;
GyYo = GyYo/20;
GyZo = GyZo/20;*/
}
curr = (AcZ - AcZo / 100);
if (prev == curr )
++glc;
else
{
glc = 0;
prev = curr;
}
if (glc == 10 )
{
Serial.println("lock broken!!!");
glc = 0;
loop();
}
if (flag == 1 && flaggl == 1)
{
if (lv2 < 21)
{
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
distance= duration*0 distance = duration * 0.034 / 2;
AcXd += (AcX - AcXo) / 100;
AcYd += (AcY - AcYo) / 100;
AcZd += (AcZ - AcZo) /100; 100;
yprd[0] += ypr[0] * 180 / M_PI - yo;
yprd[1] += ypr[1] * 180 / M_PI - po;
yprd[2] += ypr[2] * 180 / M_PI - ro;
distanced += distance;
++lv2;
}
else
} else {
AcXd /= 20;
AcYd /= 20;
AcZd /= 20;
yprd[0] /= 20;
yprd[1] /= 20;
yprd[2] /= 20;
distanced /= 20;
lv2 = 1;
Serial.print("AcX = ");
Serial.print(AcXd);
Serial.print(" | AcY = ");
Serial.print(AcYd);
Serial.print(" | AcZ = ");
Serial.print(AcZd);
Serial.print(" | yaw = ");
Serial.print(yprd[0]);
Serial.print(" | pitch = ");
Serial.print(yprd[1]);
Serial.print(" | roll = ");
Serial.print(yprd[2]);
Serial.print(" | distance = ");
Serial.println(distanced);
AcXd = 0;
AcYd = 0;
AcZd =0;= 0;
yprd[0] = 0;
yprd[1] = 0;
yprd[2] = 0;
distanced = 0;
}
}
}
}
/*Serial.print("AcX = "); Serial.print((AcX - AcXo)/100);
Serial.print(" | AcY = "); Serial.print((AcY - AcYo)/100);
Serial.print(" | AcZ = "); Serial.print((AcZ - AcZo)/100);*/
/*Serial.print(" | Tmp = "); Serial.print(Tmp/340.00+36.53 - Tmpo);
//equation for temperature in degrees C from datasheet
/*Serial.print(" | GyX = "); Serial.print((GyX - GyXo)/100);
Serial.print(" | GyY = "); Serial.print((GyY - GyYo)/100);
Serial.print(" | GyZ = "); Serial.println((GyZ - GyZo)/100);*/
}
}
The code involves offset calculation and displays the averaged instantaneous values. After overcoming the problems of FIFO buffer overflow and some other typical issues, I've managed to get the code running but the the Arduino hangs after sometime (code tested on both Uno and nanoNano).
Therefore, it seems that maybe I need a higher clock speed . So, I had a look through other Arduino boards and Due seemed to be the solution, as it has a clock speed of 84MHz, compared to Uno's 16 MHz. Therefore, my question is that will be the libraries and functions used in this code be compatiablecompatible with the Due? Also, can the 3.3V operation of the Due, compared to Uno's 5V, present any problem in interfacing it with other sensors mentioned?
