mirror of
https://github.com/okalachev/flix.git
synced 2026-06-28 05:56:44 +00:00
Oleg Kalachev
57e83040b8
Accelerometer gives only motors specific force in flight, which makes it useless to determine the current vertial
50 lines
1.1 KiB
Arduino
50 lines
1.1 KiB
Arduino
// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
|
|
// Repository: https://github.com/okalachev/flix
|
|
|
|
// Attitude estimation from gyro and accelerometer
|
|
|
|
#include "quaternion.h"
|
|
#include "vector.h"
|
|
|
|
#define ONE_G 9.807f
|
|
#define ACC_MIN 0.9f
|
|
#define ACC_MAX 1.1f
|
|
#define WEIGHT_ACC 0.5f
|
|
|
|
void estimate()
|
|
{
|
|
applyGyro();
|
|
applyAcc();
|
|
signalizeHorizontality();
|
|
}
|
|
|
|
void applyGyro()
|
|
{
|
|
// applying gyro
|
|
attitude *= Quaternion::fromAngularRates(rates * dt);
|
|
attitude.normalize();
|
|
}
|
|
|
|
void applyAcc()
|
|
{
|
|
// test should we apply accelerometer gravity correction
|
|
float accNorm = acc.norm();
|
|
bool landed = !motorsActive() && abs(accNorm - ONE_G) < ONE_G * 0.1f;
|
|
|
|
if (!landed) return;
|
|
|
|
// calculate accelerometer correction
|
|
Vector up = attitude.rotate(Vector(0, 0, -1));
|
|
Vector correction = Vector::angularRatesBetweenVectors(acc, up) * dt * WEIGHT_ACC;
|
|
|
|
// apply correction
|
|
attitude *= Quaternion::fromAngularRates(correction);
|
|
attitude.normalize();
|
|
}
|
|
|
|
void signalizeHorizontality()
|
|
{
|
|
float angle = Vector::angleBetweenVectors(attitude.rotate(Vector(0, 0, -1)), Vector(0, 0, -1));
|
|
setLED(angle < 15 * DEG_TO_RAD);
|
|
}
|