1
0
mirror of https://bitbucket.org/librepilot/librepilot.git synced 2024-11-29 07:24:13 +01:00
LibrePilot/flight/libraries/plans.c

783 lines
30 KiB
C

/**
******************************************************************************
*
* @file plan.c
* @author The LibrePilot Project, http://www.librepilot.org Copyright (C) 2016.
* The OpenPilot Team, http://www.openpilot.org Copyright (C) 2015.
*
* @brief setups RTH/PH and other pathfollower/pathplanner status
*
* @see The GNU Public License (GPL) Version 3
*
* @addtogroup LibrePilotLibraries LibrePilot Libraries Navigation
******************************************************************************/
/*
* 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 <plans.h>
#include <openpilot.h>
#include <attitudesettings.h>
#include <takeofflocation.h>
#include <pathdesired.h>
#include <positionstate.h>
#include <flightmodesettings.h>
#include <flightstatus.h>
#include <velocitystate.h>
#include <manualcontrolcommand.h>
#include <attitudestate.h>
#include <vtolpathfollowersettings.h>
#include <stabilizationbank.h>
#include <stabilizationdesired.h>
#include <sin_lookup.h>
#include <sanitycheck.h>
#include <statusvtolautotakeoff.h>
#define UPDATE_EXPECTED 0.02f
#define UPDATE_MIN 1.0e-6f
#define UPDATE_MAX 1.0f
#define UPDATE_ALPHA 1.0e-2f
static float applyExpo(float value, float expo);
static float applyExpo(float value, float expo)
{
// note: fastPow makes a small error, therefore result needs to be bound
float exp = boundf(fastPow(1.00695f, expo), 0.5f, 2.0f);
// magic number scales expo
// so that
// expo=100 yields value**10
// expo=0 yields value**1
// expo=-100 yields value**(1/10)
// (pow(2.0,1/100)~=1.00695)
if (value > 0.0f) {
return boundf(fastPow(value, exp), 0.0f, 1.0f);
} else if (value < -0.0f) {
return boundf(-fastPow(-value, exp), -1.0f, 0.0f);
} else {
return 0.0f;
}
}
/**
* @brief initialize UAVOs and structs used by this library
*/
void plan_initialize()
{
PositionStateInitialize();
PathDesiredInitialize();
FlightStatusInitialize();
AttitudeStateInitialize();
ManualControlCommandInitialize();
VelocityStateInitialize();
StabilizationBankInitialize();
StabilizationDesiredInitialize();
}
/**
* @brief setup pathplanner/pathfollower for positionhold
*/
void plan_setup_positionHold()
{
PositionStateData positionState;
PositionStateGet(&positionState);
PathDesiredData pathDesired;
// re-initialise in setup stage
memset(&pathDesired, 0, sizeof(PathDesiredData));
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
pathDesired.End.North = positionState.North;
pathDesired.End.East = positionState.East;
pathDesired.End.Down = positionState.Down;
pathDesired.Start.North = positionState.North + offset.Horizontal; // in FlyEndPoint the direction of this vector does not matter
pathDesired.Start.East = positionState.East;
pathDesired.Start.Down = positionState.Down;
pathDesired.StartingVelocity = 0.0f;
pathDesired.EndingVelocity = 0.0f;
pathDesired.Mode = PATHDESIRED_MODE_GOTOENDPOINT;
PathDesiredSet(&pathDesired);
}
/**
* @brief setup pathplanner/pathfollower for return to base
*/
void plan_setup_returnToBase()
{
// Simple Return To Base mode - keep altitude the same applying configured delta, fly to takeoff position
float positionStateDown;
PositionStateDownGet(&positionStateDown);
PathDesiredData pathDesired;
// re-initialise in setup stage
memset(&pathDesired, 0, sizeof(PathDesiredData));
TakeOffLocationData takeoffLocation;
TakeOffLocationGet(&takeoffLocation);
// TODO: right now VTOLPF does fly straight to destination altitude.
// For a safer RTB destination altitude will be the higher between takeofflocation and current position (corrected with safety margin)
float destDown;
float destVelocity;
FlightModeSettingsReturnToBaseAltitudeOffsetGet(&destDown);
FlightModeSettingsReturnToBaseVelocityGet(&destVelocity);
destDown = MIN(positionStateDown, takeoffLocation.Down) - destDown;
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
pathDesired.End.North = takeoffLocation.North;
pathDesired.End.East = takeoffLocation.East;
pathDesired.End.Down = destDown;
pathDesired.Start.North = takeoffLocation.North + offset.Horizontal; // in FlyEndPoint the direction of this vector does not matter
pathDesired.Start.East = takeoffLocation.East;
pathDesired.Start.Down = destDown;
pathDesired.StartingVelocity = destVelocity;
pathDesired.EndingVelocity = destVelocity;
FlightModeSettingsReturnToBaseNextCommandOptions ReturnToBaseNextCommand;
FlightModeSettingsReturnToBaseNextCommandGet(&ReturnToBaseNextCommand);
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_GOTOENDPOINT_NEXTCOMMAND] = (float)ReturnToBaseNextCommand;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_GOTOENDPOINT_UNUSED1] = 0.0f;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_GOTOENDPOINT_UNUSED2] = 0.0f;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_GOTOENDPOINT_UNUSED3] = 0.0f;
pathDesired.Mode = PATHDESIRED_MODE_GOTOENDPOINT;
PathDesiredSet(&pathDesired);
}
void plan_setup_AutoTakeoff()
{
PathDesiredData pathDesired;
memset(&pathDesired, 0, sizeof(PathDesiredData));
PositionStateData positionState;
PositionStateGet(&positionState);
float autotakeoff_height;
FlightModeSettingsAutoTakeOffHeightGet(&autotakeoff_height);
autotakeoff_height = fabsf(autotakeoff_height);
pathDesired.Start.North = positionState.North;
pathDesired.Start.East = positionState.East;
pathDesired.Start.Down = positionState.Down;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_AUTOTAKEOFF_NORTH] = 0.0f;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_AUTOTAKEOFF_EAST] = 0.0f;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_AUTOTAKEOFF_DOWN] = 0.0f;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_AUTOTAKEOFF_CONTROLSTATE] = 0.0f;
pathDesired.End.North = positionState.North;
pathDesired.End.East = positionState.East;
pathDesired.End.Down = positionState.Down - autotakeoff_height;
pathDesired.StartingVelocity = 0.0f;
pathDesired.EndingVelocity = 0.0f;
pathDesired.Mode = PATHDESIRED_MODE_AUTOTAKEOFF;
PathDesiredSet(&pathDesired);
}
static void plan_setup_land_helper(PathDesiredData *pathDesired)
{
PositionStateData positionState;
PositionStateGet(&positionState);
float velocity_down;
FlightModeSettingsLandingVelocityGet(&velocity_down);
pathDesired->Start.North = positionState.North;
pathDesired->Start.East = positionState.East;
pathDesired->Start.Down = positionState.Down;
pathDesired->ModeParameters[PATHDESIRED_MODEPARAMETER_LAND_VELOCITYVECTOR_NORTH] = 0.0f;
pathDesired->ModeParameters[PATHDESIRED_MODEPARAMETER_LAND_VELOCITYVECTOR_EAST] = 0.0f;
pathDesired->ModeParameters[PATHDESIRED_MODEPARAMETER_LAND_VELOCITYVECTOR_DOWN] = velocity_down;
pathDesired->End.North = positionState.North;
pathDesired->End.East = positionState.East;
pathDesired->End.Down = positionState.Down;
pathDesired->StartingVelocity = 0.0f;
pathDesired->EndingVelocity = 0.0f;
pathDesired->Mode = PATHDESIRED_MODE_LAND;
pathDesired->ModeParameters[PATHDESIRED_MODEPARAMETER_LAND_OPTIONS] = (float)PATHDESIRED_MODEPARAMETER_LAND_OPTION_HORIZONTAL_PH;
}
void plan_setup_land()
{
PathDesiredData pathDesired;
// re-initialise in setup stage
memset(&pathDesired, 0, sizeof(PathDesiredData));
plan_setup_land_helper(&pathDesired);
PathDesiredSet(&pathDesired);
}
static void plan_setup_land_from_velocityroam()
{
plan_setup_land();
FlightStatusAssistedControlStateOptions assistedControlFlightMode;
assistedControlFlightMode = FLIGHTSTATUS_ASSISTEDCONTROLSTATE_HOLD;
FlightStatusAssistedControlStateSet(&assistedControlFlightMode);
}
/**
* @brief positionvario functionality
*/
static bool vario_hold = true;
static float hold_position[3];
static float vario_control_lowpass[3];
static float vario_course = 0.0f;
static void plan_setup_PositionVario()
{
vario_hold = true;
vario_control_lowpass[0] = 0.0f;
vario_control_lowpass[1] = 0.0f;
vario_control_lowpass[2] = 0.0f;
AttitudeStateYawGet(&vario_course);
plan_setup_positionHold();
}
void plan_setup_CourseLock()
{
plan_setup_PositionVario();
}
void plan_setup_PositionRoam()
{
plan_setup_PositionVario();
}
void plan_setup_VelocityRoam()
{
vario_control_lowpass[0] = 0.0f;
vario_control_lowpass[1] = 0.0f;
vario_control_lowpass[2] = 0.0f;
AttitudeStateYawGet(&vario_course);
}
void plan_setup_HomeLeash()
{
plan_setup_PositionVario();
}
void plan_setup_AbsolutePosition()
{
plan_setup_PositionVario();
}
#define DEADBAND 0.1f
static bool normalizeDeadband(float controlVector[4])
{
bool moving = false;
// roll, pitch, yaw between -1 and +1
// thrust between 0 and 1 mapped to -1 to +1
controlVector[3] = (2.0f * controlVector[3]) - 1.0f;
int t;
for (t = 0; t < 4; t++) {
if (controlVector[t] < -DEADBAND) {
moving = true;
controlVector[t] += DEADBAND;
} else if (controlVector[t] > DEADBAND) {
moving = true;
controlVector[t] -= DEADBAND;
} else {
controlVector[t] = 0.0f;
}
// deadband has been cut out, scale value back to [-1,+1]
controlVector[t] *= (1.0f / (1.0f - DEADBAND));
controlVector[t] = boundf(controlVector[t], -1.0f, 1.0f);
}
return moving;
}
typedef enum { COURSE, FPV, LOS, NSEW } vario_type;
static void getVector(float controlVector[4], vario_type type)
{
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
// scale controlVector[3] (thrust) by vertical/horizontal to have vertical plane less sensitive
controlVector[3] *= offset.Vertical / offset.Horizontal;
float length = sqrtf(controlVector[0] * controlVector[0] + controlVector[1] * controlVector[1] + controlVector[3] * controlVector[3]);
if (length <= 1e-9f) {
length = 1.0f; // should never happen as getVector is not called if control within deadband
}
{
float direction[3] = {
controlVector[1] / length, // pitch is north
controlVector[0] / length, // roll is east
controlVector[3] / length // thrust is down
};
controlVector[0] = direction[0];
controlVector[1] = direction[1];
controlVector[2] = direction[2];
}
controlVector[3] = length * offset.Horizontal;
// rotate north and east - rotation angle based on type
float angle;
switch (type) {
case COURSE:
angle = vario_course;
break;
case NSEW:
angle = 0.0f;
// NSEW no rotation takes place
break;
case FPV:
// local rotation, using current yaw
AttitudeStateYawGet(&angle);
break;
case LOS:
// determine location based on vector from takeoff to current location
{
PositionStateData positionState;
PositionStateGet(&positionState);
TakeOffLocationData takeoffLocation;
TakeOffLocationGet(&takeoffLocation);
angle = RAD2DEG(atan2f(positionState.East - takeoffLocation.East, positionState.North - takeoffLocation.North));
}
break;
}
// rotate horizontally by angle
{
float rotated[2] = {
controlVector[0] * cos_lookup_deg(angle) - controlVector[1] * sin_lookup_deg(angle),
controlVector[0] * sin_lookup_deg(angle) + controlVector[1] * cos_lookup_deg(angle)
};
controlVector[0] = rotated[0];
controlVector[1] = rotated[1];
}
}
static void plan_run_PositionVario(vario_type type)
{
float controlVector[4];
float alpha;
PathDesiredData pathDesired;
// Reuse the existing pathdesired object as setup in the setup to avoid
// updating values already set.
PathDesiredGet(&pathDesired);
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
ManualControlCommandRollGet(&controlVector[0]);
ManualControlCommandPitchGet(&controlVector[1]);
ManualControlCommandYawGet(&controlVector[2]);
ManualControlCommandThrustGet(&controlVector[3]);
FlightModeSettingsVarioControlLowPassAlphaGet(&alpha);
vario_control_lowpass[0] = alpha * vario_control_lowpass[0] + (1.0f - alpha) * controlVector[0];
vario_control_lowpass[1] = alpha * vario_control_lowpass[1] + (1.0f - alpha) * controlVector[1];
vario_control_lowpass[2] = alpha * vario_control_lowpass[2] + (1.0f - alpha) * controlVector[2];
controlVector[0] = vario_control_lowpass[0];
controlVector[1] = vario_control_lowpass[1];
controlVector[2] = vario_control_lowpass[2];
// check if movement is desired
if (normalizeDeadband(controlVector) == false) {
// no movement desired, re-enter positionHold at current start-position
if (!vario_hold) {
vario_hold = true;
// new hold position is the position that was previously the start position
pathDesired.End.North = hold_position[0];
pathDesired.End.East = hold_position[1];
pathDesired.End.Down = hold_position[2];
// while the new start position has the same offset as in position hold
pathDesired.Start.North = pathDesired.End.North + offset.Horizontal; // in FlyEndPoint the direction of this vector does not matter
pathDesired.Start.East = pathDesired.End.East;
pathDesired.Start.Down = pathDesired.End.Down;
// set mode explicitly
PathDesiredSet(&pathDesired);
}
} else {
PositionStateData positionState;
PositionStateGet(&positionState);
// flip pitch to have pitch down (away) point north
controlVector[1] = -controlVector[1];
getVector(controlVector, type);
// layout of control Vector : unitVector in movement direction {0,1,2} vector length {3} velocity {4}
if (vario_hold) {
// start position is the position that was previously the hold position
vario_hold = false;
hold_position[0] = pathDesired.End.North;
hold_position[1] = pathDesired.End.East;
hold_position[2] = pathDesired.End.Down;
} else {
// start position is advanced according to movement - in the direction of ControlVector only
// projection using scalar product
float kp = (positionState.North - hold_position[0]) * controlVector[0]
+ (positionState.East - hold_position[1]) * controlVector[1]
+ (positionState.Down - hold_position[2]) * -controlVector[2];
if (kp > 0.0f) {
hold_position[0] += kp * controlVector[0];
hold_position[1] += kp * controlVector[1];
hold_position[2] += kp * -controlVector[2];
}
}
// new destination position is advanced based on controlVector
pathDesired.End.North = hold_position[0] + controlVector[0] * controlVector[3];
pathDesired.End.East = hold_position[1] + controlVector[1] * controlVector[3];
pathDesired.End.Down = hold_position[2] - controlVector[2] * controlVector[3];
// the new start position has the same offset as in position hold
pathDesired.Start.North = pathDesired.End.North + offset.Horizontal; // in FlyEndPoint the direction of this vector does not matter
pathDesired.Start.East = pathDesired.End.East;
pathDesired.Start.Down = pathDesired.End.Down;
PathDesiredSet(&pathDesired);
}
}
void plan_run_VelocityRoam()
{
// float alpha;
PathDesiredData pathDesired;
// velocity roam code completely sets pathdesired object. it was not set in setup phase
memset(&pathDesired, 0, sizeof(PathDesiredData));
FlightStatusAssistedControlStateOptions assistedControlFlightMode;
FlightStatusFlightModeOptions flightMode;
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
FlightStatusAssistedControlStateGet(&assistedControlFlightMode);
FlightStatusFlightModeGet(&flightMode);
StabilizationBankData stabSettings;
StabilizationBankGet(&stabSettings);
ManualControlCommandData cmd;
ManualControlCommandGet(&cmd);
cmd.Roll = applyExpo(cmd.Roll, stabSettings.StickExpo.Roll);
cmd.Pitch = applyExpo(cmd.Pitch, stabSettings.StickExpo.Pitch);
cmd.Yaw = applyExpo(cmd.Yaw, stabSettings.StickExpo.Yaw);
bool flagRollPitchHasInput = (fabsf(cmd.Roll) > 0.0f || fabsf(cmd.Pitch) > 0.0f);
if (!flagRollPitchHasInput) {
// no movement desired, re-enter positionHold at current start-position
if (assistedControlFlightMode == FLIGHTSTATUS_ASSISTEDCONTROLSTATE_PRIMARY) {
// initiate braking and change assisted control flight mode to braking
if (flightMode == FLIGHTSTATUS_FLIGHTMODE_LAND) {
// avoid brake then hold sequence to continue descent.
plan_setup_land_from_velocityroam();
} else {
plan_setup_assistedcontrol();
}
}
// otherwise nothing to do in braking/hold modes
} else {
PositionStateData positionState;
PositionStateGet(&positionState);
// Revert assist control state to primary, which in this case implies
// we are in roaming state (a GPS vector assisted velocity roam)
assistedControlFlightMode = FLIGHTSTATUS_ASSISTEDCONTROLSTATE_PRIMARY;
// Calculate desired velocity in each direction
float angle;
AttitudeStateYawGet(&angle);
angle = DEG2RAD(angle);
float cos_angle = cosf(angle);
float sine_angle = sinf(angle);
float rotated[2] = {
-cmd.Pitch * cos_angle - cmd.Roll * sine_angle,
-cmd.Pitch * sine_angle + cmd.Roll * cos_angle
};
// flip pitch to have pitch down (away) point north
float horizontalVelMax;
float verticalVelMax;
VtolPathFollowerSettingsHorizontalVelMaxGet(&horizontalVelMax);
VtolPathFollowerSettingsVerticalVelMaxGet(&verticalVelMax);
float velocity_north = rotated[0] * horizontalVelMax;
float velocity_east = rotated[1] * horizontalVelMax;
float velocity_down = 0.0f;
if (flightMode == FLIGHTSTATUS_FLIGHTMODE_LAND) {
FlightModeSettingsLandingVelocityGet(&velocity_down);
}
float velocity = velocity_north * velocity_north + velocity_east * velocity_east;
velocity = sqrtf(velocity);
// if one stick input (pitch or roll) should we use fly by vector? set arbitrary distance of say 20m after which we
// expect new stick input
// if two stick input pilot is fighting wind manually and we use fly by velocity
// in reality setting velocity desired to zero will fight wind anyway.
pathDesired.Start.North = positionState.North;
pathDesired.Start.East = positionState.East;
pathDesired.Start.Down = positionState.Down;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_VELOCITY_VELOCITYVECTOR_NORTH] = velocity_north;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_VELOCITY_VELOCITYVECTOR_EAST] = velocity_east;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_VELOCITY_VELOCITYVECTOR_DOWN] = velocity_down;
pathDesired.End.North = positionState.North;
pathDesired.End.East = positionState.East;
pathDesired.End.Down = positionState.Down;
pathDesired.StartingVelocity = velocity;
pathDesired.EndingVelocity = velocity;
pathDesired.Mode = PATHDESIRED_MODE_VELOCITY;
if (flightMode == FLIGHTSTATUS_FLIGHTMODE_LAND) {
pathDesired.Mode = PATHDESIRED_MODE_LAND;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_LAND_OPTIONS] = (float)PATHDESIRED_MODEPARAMETER_LAND_OPTION_NONE;
} else {
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_VELOCITY_UNUSED] = 0.0f;
}
PathDesiredSet(&pathDesired);
FlightStatusAssistedControlStateSet(&assistedControlFlightMode);
}
}
void plan_run_CourseLock()
{
plan_run_PositionVario(COURSE);
}
void plan_run_PositionRoam()
{
plan_run_PositionVario(FPV);
}
void plan_run_HomeLeash()
{
plan_run_PositionVario(LOS);
}
void plan_run_AbsolutePosition()
{
plan_run_PositionVario(NSEW);
}
/**
* @brief setup pathplanner/pathfollower for AutoCruise
*/
static PiOSDeltatimeConfig actimeval;
void plan_setup_AutoCruise()
{
PositionStateData positionState;
PositionStateGet(&positionState);
PathDesiredData pathDesired;
// setup needs to reinitialise the pathdesired object
memset(&pathDesired, 0, sizeof(PathDesiredData));
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
// initialization is flight in direction of the nose.
// the velocity is not relevant, as it will be reset by the run function even during first call
float angle;
AttitudeStateYawGet(&angle);
float vector[2] = {
cos_lookup_deg(angle),
sin_lookup_deg(angle)
};
hold_position[0] = positionState.North;
hold_position[1] = positionState.East;
hold_position[2] = positionState.Down;
pathDesired.End.North = hold_position[0] + vector[0];
pathDesired.End.East = hold_position[1] + vector[1];
pathDesired.End.Down = hold_position[2];
// start position has the same offset as in position hold
pathDesired.Start.North = pathDesired.End.North + offset.Horizontal; // in FlyEndPoint the direction of this vector does not matter
pathDesired.Start.East = pathDesired.End.East;
pathDesired.Start.Down = pathDesired.End.Down;
pathDesired.StartingVelocity = 0.0f;
pathDesired.EndingVelocity = 0.0f;
pathDesired.Mode = PATHDESIRED_MODE_GOTOENDPOINT;
PathDesiredSet(&pathDesired);
// re-iniztializing deltatime is valid and also good practice here since
// getAverageSeconds() has not been called/updated in a long time if we were in a different flightmode.
PIOS_DELTATIME_Init(&actimeval, UPDATE_EXPECTED, UPDATE_MIN, UPDATE_MAX, UPDATE_ALPHA);
}
/**
* @brief execute autocruise
*/
void plan_run_AutoCruise()
{
PositionStateData positionState;
PositionStateGet(&positionState);
PathDesiredData pathDesired;
// re-use pathdesired that was setup correctly in setup stage.
PathDesiredGet(&pathDesired);
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
float controlVector[4];
ManualControlCommandRollGet(&controlVector[0]);
ManualControlCommandPitchGet(&controlVector[1]);
ManualControlCommandYawGet(&controlVector[2]);
controlVector[3] = 0.5f; // dummy, thrust is normalized separately
normalizeDeadband(controlVector); // return value ignored
ManualControlCommandThrustGet(&controlVector[3]); // no deadband as we are using thrust for velocity
controlVector[3] = boundf(controlVector[3], 1e-6f, 1.0f); // bound to above zero, to prevent loss of vector direction
// normalize old desired movement vector
float vector[3] = { pathDesired.End.North - hold_position[0],
pathDesired.End.East - hold_position[1],
pathDesired.End.Down - hold_position[2] };
float length = sqrtf(vector[0] * vector[0] + vector[1] * vector[1] + vector[2] * vector[2]);
if (length < 1e-9f) {
length = 1.0f; // should not happen since initialized properly in setup()
}
vector[0] /= length;
vector[1] /= length;
vector[2] /= length;
// start position is advanced according to actual movement - in the direction of desired vector only
// projection using scalar product
float kp = (positionState.North - hold_position[0]) * vector[0]
+ (positionState.East - hold_position[1]) * vector[1]
+ (positionState.Down - hold_position[2]) * vector[2];
if (kp > 0.0f) {
hold_position[0] += kp * vector[0];
hold_position[1] += kp * vector[1];
hold_position[2] += kp * vector[2];
}
// new angle is equal to old angle plus offset depending on yaw input and time
// (controlVector is normalized with a deadband, change is zero within deadband)
float angle = RAD2DEG(atan2f(vector[1], vector[0]));
float dT = PIOS_DELTATIME_GetAverageSeconds(&actimeval);
angle += 10.0f * controlVector[2] * dT; // TODO magic value could eventually end up in a to be created settings
// resulting movement vector is scaled by velocity demand in controlvector[3] [0.0-1.0]
vector[0] = cosf(DEG2RAD(angle)) * offset.Horizontal * controlVector[3];
vector[1] = sinf(DEG2RAD(angle)) * offset.Horizontal * controlVector[3];
vector[2] = -controlVector[1] * offset.Vertical * controlVector[3];
pathDesired.End.North = hold_position[0] + vector[0];
pathDesired.End.East = hold_position[1] + vector[1];
pathDesired.End.Down = hold_position[2] + vector[2];
// start position has the same offset as in position hold
pathDesired.Start.North = pathDesired.End.North + offset.Horizontal; // in FlyEndPoint the direction of this vector does not matter
pathDesired.Start.East = pathDesired.End.East;
pathDesired.Start.Down = pathDesired.End.Down;
PathDesiredSet(&pathDesired);
}
/**
* @brief setup pathplanner/pathfollower for braking in positionroam
* timeout_occurred = false: Attempt to enter flyvector for braking
* timeout_occurred = true: Revert to position hold
*/
#define ASSISTEDCONTROL_BRAKERATE_MINIMUM 0.2f // m/s2
#define ASSISTEDCONTROL_TIMETOSTOP_MINIMUM 0.2f // seconds
#define ASSISTEDCONTROL_TIMETOSTOP_MAXIMUM 9.0f // seconds
#define ASSISTEDCONTROL_DELAY_TO_BRAKE 1.0f // seconds
#define ASSISTEDCONTROL_TIMEOUT_MULTIPLIER 4.0f // actual deceleration rate can be 50% of desired...timeouts need to cater for this
void plan_setup_assistedcontrol()
{
PositionStateData positionState;
PositionStateGet(&positionState);
PathDesiredData pathDesired;
// setup function, avoid carry over from previous mode
memset(&pathDesired, 0, sizeof(PathDesiredData));
FlightStatusAssistedControlStateOptions assistedControlFlightMode;
VelocityStateData velocityState;
VelocityStateGet(&velocityState);
float brakeRate;
VtolPathFollowerSettingsBrakeRateGet(&brakeRate);
if (brakeRate < ASSISTEDCONTROL_BRAKERATE_MINIMUM) {
brakeRate = ASSISTEDCONTROL_BRAKERATE_MINIMUM; // set a minimum to avoid a divide by zero potential below
}
// Calculate the velocity
float velocity = velocityState.North * velocityState.North + velocityState.East * velocityState.East + velocityState.Down * velocityState.Down;
velocity = sqrtf(velocity);
// Calculate the desired time to zero velocity.
float time_to_stopped = ASSISTEDCONTROL_DELAY_TO_BRAKE; // we allow at least 0.5 seconds to rotate to a brake angle.
time_to_stopped += velocity / brakeRate;
// Sanity check the brake rate by ensuring that the time to stop is within a range.
if (time_to_stopped < ASSISTEDCONTROL_TIMETOSTOP_MINIMUM) {
time_to_stopped = ASSISTEDCONTROL_TIMETOSTOP_MINIMUM;
} else if (time_to_stopped > ASSISTEDCONTROL_TIMETOSTOP_MAXIMUM) {
time_to_stopped = ASSISTEDCONTROL_TIMETOSTOP_MAXIMUM;
}
// calculate the distance we will travel
float north_delta = velocityState.North * ASSISTEDCONTROL_DELAY_TO_BRAKE; // we allow at least 0.5s to rotate to brake angle
north_delta += (time_to_stopped - ASSISTEDCONTROL_DELAY_TO_BRAKE) * 0.5f * velocityState.North; // area under the linear deceleration plot
float east_delta = velocityState.East * ASSISTEDCONTROL_DELAY_TO_BRAKE; // we allow at least 0.5s to rotate to brake angle
east_delta += (time_to_stopped - ASSISTEDCONTROL_DELAY_TO_BRAKE) * 0.5f * velocityState.East; // area under the linear deceleration plot
float down_delta = velocityState.Down * ASSISTEDCONTROL_DELAY_TO_BRAKE;
down_delta += (time_to_stopped - ASSISTEDCONTROL_DELAY_TO_BRAKE) * 0.5f * velocityState.Down; // area under the linear deceleration plot
float net_delta = east_delta * east_delta + north_delta * north_delta + down_delta * down_delta;
net_delta = sqrtf(net_delta);
pathDesired.Start.North = positionState.North;
pathDesired.Start.East = positionState.East;
pathDesired.Start.Down = positionState.Down;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_BRAKE_STARTVELOCITYVECTOR_NORTH] = velocityState.North;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_BRAKE_STARTVELOCITYVECTOR_EAST] = velocityState.East;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_BRAKE_STARTVELOCITYVECTOR_DOWN] = velocityState.Down;
pathDesired.End.North = positionState.North + north_delta;
pathDesired.End.East = positionState.East + east_delta;
pathDesired.End.Down = positionState.Down + down_delta;
pathDesired.StartingVelocity = velocity;
pathDesired.EndingVelocity = 0.0f;
pathDesired.Mode = PATHDESIRED_MODE_BRAKE;
pathDesired.ModeParameters[PATHDESIRED_MODEPARAMETER_BRAKE_TIMEOUT] = time_to_stopped * ASSISTEDCONTROL_TIMEOUT_MULTIPLIER;
assistedControlFlightMode = FLIGHTSTATUS_ASSISTEDCONTROLSTATE_BRAKE;
FlightStatusAssistedControlStateSet(&assistedControlFlightMode);
PathDesiredSet(&pathDesired);
}