code :
#include <Wire.h>
#include <I2Cdev.h>
#include <Servo.h>
#include "MPU6050_6Axis_MotionApps20.h"
MPU6050 mpu;
#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; // return status after each device operation (0 = success, !0 = error)
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]; // [yaw, pitch, roll] yaw/pitch/roll container and gravity vector
int x = 0;
volatile bool mpuInterrupt = false; // indicates whether MPU interrupt pin has gone high
void dmpDataReady() {
mpuInterrupt = true;
}
//define Kp,Ki,Kd
float kp[3], ki[3], kd[3];
//define PID variable (error, setpoint, mesure, error sum, error variation, last error and output)
float yprMesure[3], yprPidResult[3], yprOutput[3], yprError[3], yprAddError[3], yprVarError[3], yprLastError[3], yprSetpoint[3];
float rcControllerOutput[3];
float yprAngle[3];
//define ESC
Servo esc1;
Servo esc2;
Servo esc3;
Servo esc4;
void setup()
{
Wire.begin();
Serial.begin(115200);
// initialize device
Serial.println(F("Initializing I2C devices..."));
mpu.initialize();
// 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(166);
mpu.setYGyroOffset(-79);
mpu.setZGyroOffset(35);
mpu.setZAccelOffset(1590);
// 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(0, 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);
kp[0] = 10.0, kp[1] = 5.1, kp[2] = 4.5;
ki[0] = 0.055, ki[1] = 0.048, ki[2] = 0.045;
kd[0] = 18.0, kd[1] = 42, kd[2] = 50;
//attach esc to the right pin
esc3.attach(2);
esc2.attach(3);
esc1.attach(4);
esc4.attach(5);
}
inline void gyroPidAxe(float yprMesure[], float yprOutput[], float yprSetpoint[], char n)
{
//Compute error for all the 3 axis
yprError[n] = yprSetpoint[n] - yprMesure[n];
//Compute error sum for all the 3 axis
yprAddError[n] += yprError[n];
// Compute error variation for all the 3 axis
yprVarError[n] += yprError[n] - yprLastError[n];
//Compute angle correction
yprOutput[n] = kp[n] * yprError[n] + ki[n] * yprAddError[n] + kd[n] * yprVarError[n];
//Compute Last error
yprLastError[n] = yprError[n];
}
void gyroPid(float yprMesure[], float yprOutput[], float yprSetpoint[])
{
gyroPidAxe(yprMesure, yprOutput, yprSetpoint, 0);
gyroPidAxe(yprMesure, yprOutput, yprSetpoint, 1);
gyroPidAxe(yprMesure, yprOutput, yprSetpoint, 2);
}
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) {
}
// reset interrupt flag and get INT_STATUS byte
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;
// display Euler angles in degrees
mpu.dmpGetQuaternion(&q, fifoBuffer);
mpu.dmpGetGravity(&gravity, &q);
mpu.dmpGetYawPitchRoll(ypr, &q, &gravity);
//Serial.print("ypr\t");
yprAngle[0] = ypr[0] * 180/M_PI;
yprAngle[1] = ypr[1] * 180/M_PI;
yprAngle[2] = ypr[2] * 180/M_PI;
//Call the fonction every seconds (for good correction, you need at least a delay of 20ms or faster)
gyroPid(yprAngle, yprPidResult, rcControllerOutput);
//Print the corrections values for each angle
Serial.print(yprAngle[0]);
Serial.print(" ");
Serial.print(yprAngle[1]);
Serial.print(" ");
Serial.print(yprAngle[2]);
Serial.print(" ");
Serial.println(x);
yprPidResult[0] = constrain(yprPidResult[0], -5000, 5000);
yprPidResult[1] = constrain(yprPidResult[1], -5000, 5000);
yprPidResult[2] = constrain(yprPidResult[2], -5000, 5000);
yprPidResult[0] = map(yprPidResult[0], -5000, 5000, -200, 600);
yprPidResult[1] = map(yprPidResult[1], -5000, 5000, -200, 600);
yprPidResult[2] = map(yprPidResult[2], -5000, 5000, -200, 600);
esc1.write(1500 + yprPidResult[0] - yprPidResult[1] - yprPidResult[2]);
esc2.write(1500 - yprPidResult[0] + yprPidResult[1] - yprPidResult[2]);
esc3.write(1500 - yprPidResult[0] - yprPidResult[1] - yprPidResult[2]);
esc4.write(1500 + yprPidResult[0] + yprPidResult[1] + yprPidResult[2]);
// blink LED to indicate activity
blinkState = !blinkState;
digitalWrite(LED_PIN, blinkState);
}
x++;
}
The FIFO overflow was caused by my USB cable but I still research a patch for the Serial.write() bug. (something interesting is that the simple exemple I post don't work, like the old mpu6050 exemple, but the new one work ... strange)