mirror of
https://bitbucket.org/librepilot/librepilot.git
synced 2024-12-10 18:24:11 +01:00
c63540b2ec
Conflicts: flight/modules/Stabilization/stabilization.c shared/uavobjectdefinition/stabilizationsettings.xml
294 lines
15 KiB
C
294 lines
15 KiB
C
/**
|
|
******************************************************************************
|
|
* @addtogroup OpenPilotModules OpenPilot Modules
|
|
* @{
|
|
* @addtogroup StabilizationModule Stabilization Module
|
|
* @brief cruisecontrol mode
|
|
* @note This file implements the logic for a cruisecontrol
|
|
* @{
|
|
*
|
|
* @file cruisecontrol.h
|
|
* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2014.
|
|
* @brief Attitude stabilization module.
|
|
*
|
|
* @see The GNU Public License (GPL) Version 3
|
|
*
|
|
*****************************************************************************/
|
|
/*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 3 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
* for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <openpilot.h>
|
|
#include <stabilization.h>
|
|
#include <attitudestate.h>
|
|
#include <sin_lookup.h>
|
|
|
|
static float cruisecontrol_factor = 1.0f;
|
|
|
|
|
|
static inline float CruiseControlLimitThrust(float thrust)
|
|
{
|
|
// limit to user specified absolute max thrust
|
|
return boundf(thrust, stabSettings.cruiseControl.min_thrust, stabSettings.cruiseControl.max_thrust);
|
|
}
|
|
|
|
// assumes 1.0 <= factor <= 100.0
|
|
// a factor of less than 1.0 could make it return a value less than stabSettings.cruiseControl.min_thrust
|
|
// CP helis need to have min_thrust=-1
|
|
//
|
|
// multicopters need to have min_thrust=0.05 or so
|
|
// values below that will not be subject to max / min limiting
|
|
// that means thrust can be less than min
|
|
// that means multicopter motors stop spinning at low stick
|
|
static inline float CruiseControlFactorToThrust(float factor, float thrust)
|
|
{
|
|
// don't touch thrust if it's less than min_thrust
|
|
// without that test, quadcopter props will spin up
|
|
// to min thrust even at zero throttle stick
|
|
// if Cruise Control is enabled on this flight switch position
|
|
if (thrust > stabSettings.cruiseControl.min_thrust) {
|
|
return CruiseControlLimitThrust(thrust * factor);
|
|
}
|
|
return thrust;
|
|
}
|
|
|
|
static float CruiseControlAngleToFactor(float angle)
|
|
{
|
|
float factor;
|
|
|
|
// avoid singularity
|
|
if (angle > 89.999f && angle < 90.001f) {
|
|
factor = stabSettings.settings.CruiseControlMaxPowerFactor;
|
|
} else {
|
|
// the simple bank angle boost calculation that Cruise Control revolves around
|
|
factor = 1.0f / fabsf(cos_lookup_deg(angle));
|
|
// factor in the power trim, no effect at 1.0, linear effect increases with factor
|
|
factor = (factor - 1.0f) * stabSettings.cruiseControl.power_trim + 1.0f;
|
|
// limit to user specified max power multiplier
|
|
if (factor > stabSettings.settings.CruiseControlMaxPowerFactor) {
|
|
factor = stabSettings.settings.CruiseControlMaxPowerFactor;
|
|
}
|
|
}
|
|
return factor;
|
|
}
|
|
|
|
|
|
void cruisecontrol_compute_factor(AttitudeStateData *attitude, float thrustDemand)
|
|
{
|
|
static float previous_angle;
|
|
static uint32_t previous_time = 0;
|
|
static bool previous_time_valid = false;
|
|
|
|
// For multiple, speedy flips this mainly strives to address the
|
|
// fact that (due to thrust delay) thrust didn't average straight
|
|
// down, but at an angle. For less speedy flips it acts like it
|
|
// used to. It can be turned off by setting power delay to 0.
|
|
|
|
// It takes significant time for the motors of a multi-copter to
|
|
// spin up. It takes significant time for the collective servo of
|
|
// a CP heli to move from one end to the other. Both of those are
|
|
// modeled here as linear, i.e. twice as much change takes twice
|
|
// as long. Given a correctly configured maximum delay time this
|
|
// code calculates how far in advance to start the control
|
|
// transition so that half way through the physical transition it
|
|
// is just crossing the transition angle.
|
|
// Example: Rotation rate = 360. Full stroke delay = 0.2
|
|
// Transition angle 90 degrees. Start the transition 0.1 second
|
|
// before 90 degrees (36 degrees at 360 deg/sec) and it will be
|
|
// complete 0.1 seconds after 90 degrees.
|
|
|
|
// Note that this code only handles the transition to/from inverted
|
|
// thrust. It doesn't handle the case where thrust is changed a
|
|
// lot in a small angle range when that range is close to 90 degrees.
|
|
// It doesn't handle the small constant "system delay" caused by the
|
|
// delay between reading sensors and actuators beginning to respond.
|
|
// It also assumes that the pilot is holding the throttle constant;
|
|
// when the pilot does change the throttle, the compensation is
|
|
// simply recalculated.
|
|
|
|
// This implementation of future thrust isn't perfect. That would
|
|
// probably require an iterative procedure for solving a
|
|
// transcendental equation of the form linear(x) = 1/cos(x). It's
|
|
// shortcomings generally don't hurt anything and work better than
|
|
// without it. It is designed to work perfectly if the pilot is
|
|
// using full thrust during flips and it is only activated if 70% or
|
|
// greater thrust is used.
|
|
|
|
uint32_t time = PIOS_DELAY_GetuS();
|
|
|
|
// Get roll and pitch angles, calculate combined angle, and begin
|
|
// the general algorithm.
|
|
// Example: 45 degrees roll plus 45 degrees pitch = 60 degrees
|
|
// Do it every 8th iteration to save CPU.
|
|
if (time != previous_time || previous_time_valid == false) {
|
|
float angle, angle_unmodified;
|
|
|
|
// spherical right triangle
|
|
// 0.0 <= angle <= 180.0
|
|
angle_unmodified = angle = RAD2DEG(acosf(cos_lookup_deg(attitude->Roll)
|
|
* cos_lookup_deg(attitude->Pitch)));
|
|
|
|
// Calculate rate as a combined (roll and pitch) bank angle
|
|
// change; in degrees per second. Rate is calculated over the
|
|
// most recent 8 loops through stabilization. We could have
|
|
// asked the gyros. This is probably cheaper.
|
|
if (previous_time_valid) {
|
|
float rate;
|
|
|
|
// rate can be negative.
|
|
rate = (angle - previous_angle) / ((float)(time - previous_time) / 1000000.0f);
|
|
|
|
// Define "within range" to be those transitions that should
|
|
// be executing now. Recall that each impulse transition is
|
|
// spread out over a range of time / angle.
|
|
|
|
// There is only one transition and the high power level for
|
|
// it is either:
|
|
// 1/fabsf(cos(angle)) * current thrust
|
|
// or max power factor * current thrust
|
|
// or full thrust
|
|
// You can cross the transition with angle either increasing
|
|
// or decreasing (rate positive or negative).
|
|
|
|
// Thrust is never boosted for negative values of
|
|
// thrustDemand (negative stick values)
|
|
//
|
|
// When the aircraft is upright, thrust is always boosted
|
|
// . for positive values of thrustDemand
|
|
// When the aircraft is inverted, thrust is sometimes
|
|
// . boosted or reversed (or combinations thereof) or zeroed
|
|
// . for positive values of thrustDemand
|
|
// It depends on the inverted power settings.
|
|
// Of course, you can set MaxPowerFactor to 1.0 to
|
|
// . effectively disable boost.
|
|
if (thrustDemand > 0.0f) {
|
|
// to enable the future thrust calculations, make sure
|
|
// there is a large enough transition that the result
|
|
// will be roughly on vs. off; without that, it can
|
|
// exaggerate the length of time the inverted to upright
|
|
// transition holds full throttle and reduce the length
|
|
// of time for full throttle when going upright to inverted.
|
|
if (thrustDemand > 0.7f) {
|
|
float thrust;
|
|
|
|
thrust = CruiseControlFactorToThrust(CruiseControlAngleToFactor((float)stabSettings.settings.CruiseControlMaxAngle), thrustDemand);
|
|
|
|
// determine if we are in range of the transition
|
|
|
|
// given the thrust at max_angle and thrustDemand
|
|
// (typically close to 1.0), change variable 'thrust' to
|
|
// be the proportion of the largest thrust change possible
|
|
// that occurs when going into inverted mode.
|
|
// Example: 'thrust' is 0.8 A quad has min_thrust set
|
|
// to 0.05 The difference is 0.75. The largest possible
|
|
// difference with this setup is 0.9 - 0.05 = 0.85, so
|
|
// the proportion is 0.75/0.85
|
|
// That is nearly a full throttle stroke.
|
|
// the 'thrust' variable is non-negative here
|
|
switch (stabSettings.settings.CruiseControlInvertedPowerOutput) {
|
|
case STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDPOWEROUTPUT_ZERO:
|
|
// normal multi-copter case, stroke is max to zero
|
|
// technically max to constant min_thrust
|
|
// can be used by CP
|
|
thrust = (thrust - CruiseControlLimitThrust(0.0f)) / stabSettings.cruiseControl.thrust_difference;
|
|
break;
|
|
case STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDPOWEROUTPUT_NORMAL:
|
|
// reversed but not boosted
|
|
// : CP heli case, stroke is max to -stick
|
|
// : thrust = (thrust - CruiseControlLimitThrust(-thrustDemand)) / stabSettings.cruiseControl.thrust_difference;
|
|
// else it is both unreversed and unboosted
|
|
// : simply turn off boost, stroke is max to +stick
|
|
// : thrust = (thrust - CruiseControlLimitThrust(thrustDemand)) / stabSettings.cruiseControl.thrust_difference;
|
|
thrust = (thrust - CruiseControlLimitThrust(
|
|
(stabSettings.settings.CruiseControlInvertedThrustReversing
|
|
== STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDTHRUSTREVERSING_REVERSED)
|
|
? -thrustDemand
|
|
: thrustDemand)) / stabSettings.cruiseControl.thrust_difference;
|
|
break;
|
|
case STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDPOWEROUTPUT_BOOSTED:
|
|
// if boosted and reversed
|
|
if (stabSettings.settings.CruiseControlInvertedThrustReversing
|
|
== STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDTHRUSTREVERSING_REVERSED) {
|
|
// CP heli case, stroke is max to min
|
|
thrust = (thrust - CruiseControlFactorToThrust(-CruiseControlAngleToFactor((float)stabSettings.settings.CruiseControlMaxAngle), thrustDemand)) / stabSettings.cruiseControl.thrust_difference;
|
|
}
|
|
// else it is boosted and unreversed so the throttle doesn't change
|
|
else {
|
|
// CP heli case, no transition, so stroke is zero
|
|
thrust = 0.0f;
|
|
}
|
|
break;
|
|
}
|
|
|
|
// 'thrust' is now the proportion of max stroke
|
|
// multiply this proportion of max stroke,
|
|
// times the max stroke time, to get this stroke time
|
|
// we only want half of this time before the transition
|
|
// (and half after the transition)
|
|
thrust *= stabSettings.cruiseControl.half_power_delay;
|
|
// 'thrust' is now the length of time for this stroke
|
|
// multiply that times angular rate to get the lead angle
|
|
thrust *= fabsf(rate);
|
|
// if the transition is within range we use it,
|
|
// else we just use the current calculated thrust
|
|
if ((float)stabSettings.settings.CruiseControlMaxAngle - thrust <= angle
|
|
&& angle <= (float)stabSettings.settings.CruiseControlMaxAngle + thrust) {
|
|
// default to a little above max angle
|
|
angle = (float)stabSettings.settings.CruiseControlMaxAngle + 0.01f;
|
|
// if roll direction is downward
|
|
// then thrust value is taken from below max angle
|
|
// by the code that knows about the transition angle
|
|
if (rate < 0.0f) {
|
|
angle -= 0.02f;
|
|
}
|
|
}
|
|
} // if thrust > 0.7; else just use the angle we already calculated
|
|
cruisecontrol_factor = CruiseControlAngleToFactor(angle);
|
|
} else { // if thrust > 0 set factor from angle; else
|
|
cruisecontrol_factor = 1.0f;
|
|
}
|
|
|
|
if (angle >= (float)stabSettings.settings.CruiseControlMaxAngle) {
|
|
switch (stabSettings.settings.CruiseControlInvertedPowerOutput) {
|
|
case STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDPOWEROUTPUT_ZERO:
|
|
cruisecontrol_factor = 0.0f;
|
|
break;
|
|
case STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDPOWEROUTPUT_NORMAL:
|
|
cruisecontrol_factor = 1.0f;
|
|
break;
|
|
case STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDPOWEROUTPUT_BOOSTED:
|
|
// no change, leave factor >= 1.0 alone
|
|
break;
|
|
}
|
|
if (stabSettings.settings.CruiseControlInvertedThrustReversing
|
|
== STABILIZATIONSETTINGS_CRUISECONTROLINVERTEDTHRUSTREVERSING_REVERSED) {
|
|
cruisecontrol_factor = -cruisecontrol_factor;
|
|
}
|
|
}
|
|
} // if previous_time_valid i.e. we've got a rate; else leave (angle and) factor alone
|
|
previous_time = time;
|
|
previous_time_valid = true;
|
|
previous_angle = angle_unmodified;
|
|
} // every 8th time
|
|
}
|
|
|
|
float cruisecontrol_apply_factor(float raw)
|
|
{
|
|
if (stabSettings.settings.CruiseControlMaxPowerFactor > 0.0001f) {
|
|
raw = CruiseControlFactorToThrust(cruisecontrol_factor, raw);
|
|
}
|
|
return raw;
|
|
}
|