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OP-1156 fix path logic to not deviate from correct altitude too much

This commit is contained in:
Corvus Corax 2014-08-15 17:56:57 +02:00
parent 09e8b38407
commit b562fcb02e
6 changed files with 119 additions and 185 deletions

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@ -30,10 +30,10 @@
struct path_status {
float fractional_progress;
float error;
float correction_direction[3];
float path_direction[3];
float path_vector[3];
float correction_vector[3];
};
void path_progress(float *start_point, float *end_point, float *cur_point, struct path_status *status, uint8_t mode);
void path_progress(PathDesiredData *path, float *cur_point, struct path_status *status);
#endif

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@ -28,54 +28,51 @@
#include <pios_math.h>
#include <mathmisc.h>
#include "paths.h"
#include "uavobjectmanager.h" // <--.
#include "pathdesired.h" // <-- needed only for correct ENUM macro usage with path modes (PATHDESIRED_MODE_xxx,
#include "paths.h"
// no direct UAVObject usage allowed in this file
// private functions
static void path_endpoint(float *start_point, float *end_point, float *cur_point, struct path_status *status, bool mode);
static void path_vector(float *start_point, float *end_point, float *cur_point, struct path_status *status, bool mode);
static void path_circle(float *start_point, float *end_point, float *cur_point, struct path_status *status, bool clockwise);
static void path_endpoint(PathDesiredData *path, float *cur_point, struct path_status *status, bool mode);
static void path_vector(PathDesiredData *path, float *cur_point, struct path_status *status, bool mode);
static void path_circle(PathDesiredData *path, float *cur_point, struct path_status *status, bool clockwise);
/**
* @brief Compute progress along path and deviation from it
* @param[in] start_point Starting point
* @param[in] end_point Ending point
* @param[in] path PathDesired structure
* @param[in] cur_point Current location
* @param[in] mode Path following mode
* @param[out] status Structure containing progress along path and deviation
*/
void path_progress(float *start_point, float *end_point, float *cur_point, struct path_status *status, uint8_t mode)
void path_progress(PathDesiredData *path, float *cur_point, struct path_status *status)
{
switch (mode) {
switch (path->Mode) {
case PATHDESIRED_MODE_FLYVECTOR:
return path_vector(start_point, end_point, cur_point, status, true);
return path_vector(path, cur_point, status, true);
break;
case PATHDESIRED_MODE_DRIVEVECTOR:
return path_vector(start_point, end_point, cur_point, status, false);
return path_vector(path, cur_point, status, false);
break;
case PATHDESIRED_MODE_FLYCIRCLERIGHT:
case PATHDESIRED_MODE_DRIVECIRCLERIGHT:
return path_circle(start_point, end_point, cur_point, status, 1);
return path_circle(path, cur_point, status, 1);
break;
case PATHDESIRED_MODE_FLYCIRCLELEFT:
case PATHDESIRED_MODE_DRIVECIRCLELEFT:
return path_circle(start_point, end_point, cur_point, status, 0);
return path_circle(path, cur_point, status, 0);
break;
case PATHDESIRED_MODE_FLYENDPOINT:
return path_endpoint(start_point, end_point, cur_point, status, true);
return path_endpoint(path, cur_point, status, true);
break;
case PATHDESIRED_MODE_DRIVEENDPOINT:
default:
// use the endpoint as default failsafe if called in unknown modes
return path_endpoint(start_point, end_point, cur_point, status, false);
return path_endpoint(path, cur_point, status, false);
break;
}
@ -83,127 +80,120 @@ void path_progress(float *start_point, float *end_point, float *cur_point, struc
/**
* @brief Compute progress towards endpoint. Deviation equals distance
* @param[in] start_point Starting point
* @param[in] end_point Ending point
* @param[in] path PathDesired
* @param[in] cur_point Current location
* @param[out] status Structure containing progress along path and deviation
* @param[in] mode3D set true to include altitude in distance and progress calculation
*/
static void path_endpoint(float *start_point, float *end_point, float *cur_point, struct path_status *status, bool mode3D)
static void path_endpoint(PathDesiredData *path, float *cur_point, struct path_status *status, bool mode3D)
{
float path[3], diff[3];
float diff[3];
float dist_path, dist_diff;
// we do not correct in this mode
status->correction_direction[0] = status->correction_direction[1] = status->correction_direction[2] = 0;
// Distance to go
path[0] = end_point[0] - start_point[0];
path[1] = end_point[1] - start_point[1];
path[2] = mode3D ? end_point[2] - start_point[2] : 0;
status->path_vector[0] = path->End.North - path->Start.North;
status->path_vector[1] = path->End.East - path->Start.East;
status->path_vector[2] = mode3D ? path->End.Down - path->Start.Down : 0.0f;
// Current progress location relative to end
diff[0] = end_point[0] - cur_point[0];
diff[1] = end_point[1] - cur_point[1];
diff[2] = mode3D ? end_point[2] - cur_point[2] : 0;
diff[0] = path->End.North - cur_point[0];
diff[1] = path->End.East - cur_point[1];
diff[2] = mode3D ? path->End.Down - cur_point[2] : 0.0f;
dist_diff = vector_lengthf(diff, 3);
dist_path = vector_lengthf(path, 3);
dist_path = vector_lengthf(status->path_vector, 3);
if (dist_diff < 1e-6f) {
status->fractional_progress = 1;
status->error = 0;
status->path_direction[0] = status->path_direction[1] = 0;
status->path_direction[2] = 0;
status->fractional_progress = 1;
status->error = 0.0f;
status->correction_vector[0] = status->correction_vector[1] = status->correction_vector[2] = 0.0f;
// we have no base movement direction in this mode
status->path_vector[0] = status->path_vector[1] = status->path_vector[2] = 0.0f;
return;
}
if (dist_path + 1 > dist_diff) {
status->fractional_progress = 1 - dist_diff / (1 + dist_path);
if (fmaxf(dist_path, 1.0f) > dist_diff) {
status->fractional_progress = 1 - dist_diff / fmaxf(dist_path, 1.0f);
} else {
status->fractional_progress = 0; // we don't want fractional_progress to become negative
}
status->error = dist_diff;
// Compute direction to travel
status->path_direction[0] = diff[0] / dist_diff;
status->path_direction[1] = diff[1] / dist_diff;
status->path_direction[2] = diff[2] / dist_diff;
// Compute correction vector
status->correction_vector[0] = diff[0];
status->correction_vector[1] = diff[1];
status->correction_vector[2] = diff[2];
// base movement direction in this mode is a constant velocity offset on top of correction in the same direction
status->path_vector[0] = path->EndingVelocity * status->correction_vector[0] / dist_diff;
status->path_vector[1] = path->EndingVelocity * status->correction_vector[1] / dist_diff;
status->path_vector[2] = path->EndingVelocity * status->correction_vector[2] / dist_diff;
}
/**
* @brief Compute progress along path and deviation from it
* @param[in] start_point Starting point
* @param[in] end_point Ending point
* @param[in] path PathDesired
* @param[in] cur_point Current location
* @param[out] status Structure containing progress along path and deviation
* @param[in] mode3D set true to include altitude in distance and progress calculation
*/
static void path_vector(float *start_point, float *end_point, float *cur_point, struct path_status *status, bool mode3D)
static void path_vector(PathDesiredData *path, float *cur_point, struct path_status *status, bool mode3D)
{
float path[3], diff[3];
float diff[3];
float dist_path;
float dot;
float velocity;
float track_point[3];
// Distance to go
path[0] = end_point[0] - start_point[0];
path[1] = end_point[1] - start_point[1];
path[2] = mode3D ? end_point[2] - start_point[2] : 0;
status->path_vector[0] = path->End.North - path->Start.North;
status->path_vector[1] = path->End.East - path->Start.East;
status->path_vector[2] = mode3D ? path->End.Down - path->Start.Down : 0.0f;
// Current progress location relative to start
diff[0] = cur_point[0] - start_point[0];
diff[1] = cur_point[1] - start_point[1];
diff[2] = mode3D ? cur_point[2] - start_point[2] : 0;
diff[0] = cur_point[0] - path->Start.North;
diff[1] = cur_point[1] - path->Start.East;
diff[2] = mode3D ? cur_point[2] - path->Start.Down : 0.0f;
dot = path[0] * diff[0] + path[1] * diff[1] + path[2] * diff[2];
dist_path = vector_lengthf(path, 3);
dot = status->path_vector[0] * diff[0] + status->path_vector[1] * diff[1] + status->path_vector[2] * diff[2];
dist_path = vector_lengthf(status->path_vector, 3);
if (dist_path > 1e-6f) {
// Compute direction to travel & progress
status->path_direction[0] = path[0] / dist_path;
status->path_direction[1] = path[1] / dist_path;
status->path_direction[2] = path[2] / dist_path;
status->fractional_progress = dot / (dist_path * dist_path);
} else {
// Fly towards the endpoint to prevent flying away,
// but assume progress=1 either way.
path_endpoint(start_point, end_point, cur_point, status, mode3D);
path_endpoint(path, cur_point, status, mode3D);
status->fractional_progress = 1;
return;
}
// Compute point on track that is closest to our current position.
track_point[0] = status->fractional_progress * path[0] + start_point[0];
track_point[1] = status->fractional_progress * path[1] + start_point[1];
track_point[2] = status->fractional_progress * path[2] + start_point[2];
track_point[0] = status->fractional_progress * status->path_vector[0] + path->Start.North;
track_point[1] = status->fractional_progress * status->path_vector[1] + path->Start.East;
track_point[2] = status->fractional_progress * status->path_vector[2] + path->Start.Down;
status->correction_direction[0] = track_point[0] - cur_point[0];
status->correction_direction[1] = track_point[1] - cur_point[1];
status->correction_direction[2] = track_point[2] - cur_point[2];
status->correction_vector[0] = track_point[0] - cur_point[0];
status->correction_vector[1] = track_point[1] - cur_point[1];
status->correction_vector[2] = track_point[2] - cur_point[2];
status->error = vector_lengthf(status->correction_direction, 3);
status->error = vector_lengthf(status->correction_vector, 3);
// Normalize correction_direction but avoid division by zero
if (status->error > 1e-6f) {
status->correction_direction[0] /= status->error;
status->correction_direction[1] /= status->error;
status->correction_direction[2] /= status->error;
} else {
status->correction_direction[0] = 0;
status->correction_direction[1] = 0;
status->correction_direction[2] = 0;
}
// correct movement vector to current velocity
velocity = path->StartingVelocity + boundf(status->fractional_progress, 0.0f, 1.0f) * (path->EndingVelocity - path->StartingVelocity);
status->path_vector[0] = velocity * status->path_vector[0] / dist_path;
status->path_vector[1] = velocity * status->path_vector[1] / dist_path;
status->path_vector[2] = velocity * status->path_vector[2] / dist_path;
}
/**
* @brief Compute progress along circular path and deviation from it
* @param[in] start_point Starting point
* @param[in] end_point Center point
* @param[in] path PathDesired
* @param[in] cur_point Current location
* @param[out] status Structure containing progress along path and deviation
*/
static void path_circle(float *start_point, float *end_point, float *cur_point, struct path_status *status, bool clockwise)
static void path_circle(PathDesiredData *path, float *cur_point, struct path_status *status, bool clockwise)
{
float radius_north, radius_east, diff_north, diff_east, diff_down;
float radius, cradius;
@ -212,30 +202,30 @@ static void path_circle(float *start_point, float *end_point, float *cur_point,
float a_diff, a_radius;
// Radius
radius_north = end_point[0] - start_point[0];
radius_east = end_point[1] - start_point[1];
radius_north = path->End.North - path->Start.North;
radius_east = path->End.East - path->Start.East;
// Current location relative to center
diff_north = cur_point[0] - end_point[0];
diff_east = cur_point[1] - end_point[1];
diff_down = cur_point[2] - end_point[2];
diff_north = cur_point[0] - path->End.North;
diff_east = cur_point[1] - path->End.East;
diff_down = cur_point[2] - path->End.Down;
radius = sqrtf(squaref(radius_north) + squaref(radius_east));
cradius = sqrtf(squaref(diff_north) + squaref(diff_east));
// circles are always horizontal (for now - TODO: allow 3d circles - problem: clockwise/counterclockwise does no longer apply)
status->path_direction[2] = 0.0f;
status->path_vector[2] = 0.0f;
// error is current radius minus wanted radius - positive if too close
status->error = radius - cradius;
if (cradius < 1e-6f) {
// cradius is zero, just fly somewhere and make sure correction is still a normal
status->fractional_progress = 1;
status->correction_direction[0] = 0;
status->correction_direction[1] = 1;
status->path_direction[0] = 1;
status->path_direction[1] = 0;
// cradius is zero, just fly somewhere
status->fractional_progress = 1;
status->correction_vector[0] = 0;
status->correction_vector[1] = 0;
status->path_vector[0] = path->EndingVelocity;
status->path_vector[1] = 0;
} else {
if (clockwise) {
// Compute the normal to the radius clockwise
@ -270,20 +260,18 @@ static void path_circle(float *start_point, float *end_point, float *cur_point,
progress = 1.0f - progress;
}
status->fractional_progress = progress;
status->fractional_progress = progress;
// Compute direction to travel
status->path_direction[0] = normal[0];
status->path_direction[1] = normal[1];
status->path_vector[0] = normal[0] * path->EndingVelocity;
status->path_vector[1] = normal[1] * path->EndingVelocity;
// Compute direction to correct error
status->correction_direction[0] = status->error * diff_north / cradius;
status->correction_direction[1] = status->error * diff_east / cradius;
status->correction_vector[0] = status->error * diff_north / cradius;
status->correction_vector[1] = status->error * diff_east / cradius;
}
status->correction_direction[2] = -diff_down;
vector_normalizef(status->correction_direction, 3);
status->correction_vector[2] = -diff_down;
status->error = fabs(status->error);
}

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@ -70,8 +70,6 @@ void plan_setup_positionHold()
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
float startingVelocity;
FlightModeSettingsPositionHoldStartingVelocityGet(&startingVelocity);
pathDesired.End.North = positionState.North;
pathDesired.End.East = positionState.East;
@ -79,7 +77,7 @@ void plan_setup_positionHold()
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 = startingVelocity;
pathDesired.StartingVelocity = 0.0f;
pathDesired.EndingVelocity = 0.0f;
pathDesired.Mode = PATHDESIRED_MODE_FLYENDPOINT;
@ -110,8 +108,6 @@ void plan_setup_returnToBase()
destDown = MIN(positionStateDown, takeoffLocation.Down) - destDown;
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
float startingVelocity;
FlightModeSettingsPositionHoldStartingVelocityGet(&startingVelocity);
pathDesired.End.North = takeoffLocation.North;
pathDesired.End.East = takeoffLocation.East;
@ -121,7 +117,7 @@ void plan_setup_returnToBase()
pathDesired.Start.East = takeoffLocation.East;
pathDesired.Start.Down = destDown;
pathDesired.StartingVelocity = startingVelocity;
pathDesired.StartingVelocity = 0.0f;
pathDesired.EndingVelocity = 0.0f;
pathDesired.Mode = PATHDESIRED_MODE_FLYENDPOINT;
@ -131,15 +127,12 @@ void plan_setup_returnToBase()
static PiOSDeltatimeConfig landdT;
void plan_setup_land()
{
float descendspeed;
plan_setup_positionHold();
FlightModeSettingsLandingVelocityGet(&descendspeed);
PathDesiredData pathDesired;
PathDesiredGet(&pathDesired);
pathDesired.StartingVelocity = descendspeed;
pathDesired.EndingVelocity = descendspeed;
pathDesired.StartingVelocity = 0.0f;
pathDesired.EndingVelocity = 0.0f;
PathDesiredSet(&pathDesired);
PIOS_DELTATIME_Init(&landdT, UPDATE_EXPECTED, UPDATE_MIN, UPDATE_MAX, UPDATE_ALPHA);
}
@ -383,8 +376,6 @@ void plan_setup_AutoCruise()
FlightModeSettingsPositionHoldOffsetData offset;
FlightModeSettingsPositionHoldOffsetGet(&offset);
float startingVelocity;
FlightModeSettingsPositionHoldStartingVelocityGet(&startingVelocity);
// 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
@ -404,7 +395,7 @@ void plan_setup_AutoCruise()
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 = startingVelocity;
pathDesired.StartingVelocity = 0.0f;
pathDesired.EndingVelocity = 0.0f;
pathDesired.Mode = PATHDESIRED_MODE_FLYENDPOINT;

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@ -53,6 +53,7 @@
#include <CoordinateConversions.h>
#include <pios_struct_helper.h>
#include <sin_lookup.h>
#include <pathdesired.h>
#include <paths.h>
#include <sanitycheck.h>
@ -62,7 +63,6 @@
#include <vtolpathfollowersettings.h>
#include <flightstatus.h>
#include <pathstatus.h>
#include <pathdesired.h>
#include <positionstate.h>
#include <velocitystate.h>
#include <velocitydesired.h>
@ -432,12 +432,10 @@ static float updatePathBearing()
positionState.Down };
struct path_status progress;
path_progress(cast_struct_to_array(pathDesired.Start, pathDesired.Start.North),
cast_struct_to_array(pathDesired.End, pathDesired.End.North),
cur, &progress, pathDesired.Mode);
path_progress(&pathDesired, cur, &progress);
// atan2f always returns in between + and - 180 degrees
float yaw = RAD2DEG(atan2f(progress.path_direction[1], progress.path_direction[0]));
float yaw = RAD2DEG(atan2f(progress.path_vector[1], progress.path_vector[0]));
// result is in between 0 and 360 degrees
if (yaw < 0.0f) {
yaw += 360.0f;
@ -581,40 +579,13 @@ static void updatePathVelocity(float kFF, float kH, float kV, bool limited)
positionState.Down + (velocityState.Down * kFF) };
struct path_status progress;
path_progress(cast_struct_to_array(pathDesired.Start, pathDesired.Start.North),
cast_struct_to_array(pathDesired.End, pathDesired.End.North),
cur, &progress, pathDesired.Mode);
float groundspeed;
switch (pathDesired.Mode) {
case PATHDESIRED_MODE_FLYCIRCLERIGHT:
case PATHDESIRED_MODE_DRIVECIRCLERIGHT:
case PATHDESIRED_MODE_FLYCIRCLELEFT:
case PATHDESIRED_MODE_DRIVECIRCLELEFT:
groundspeed = pathDesired.EndingVelocity;
break;
case PATHDESIRED_MODE_FLYENDPOINT:
case PATHDESIRED_MODE_DRIVEENDPOINT:
case PATHDESIRED_MODE_FLYVECTOR:
case PATHDESIRED_MODE_DRIVEVECTOR:
default:
groundspeed = pathDesired.StartingVelocity + (pathDesired.EndingVelocity - pathDesired.StartingVelocity) *
boundf(progress.fractional_progress, 0.0f, 1.0f);
break;
}
// make sure groundspeed is not zero
if (limited && groundspeed < 1e-6f) {
groundspeed = 1e-6f;
}
path_progress(&pathDesired, cur, &progress);
// calculate velocity - can be zero if waypoints are too close
VelocityDesiredData velocityDesired;
velocityDesired.North = progress.path_direction[0];
velocityDesired.East = progress.path_direction[1];
velocityDesired.Down = progress.path_direction[2];
float error_speed_horizontal = progress.error * kH;
float error_speed_vertical = progress.error * kV;
velocityDesired.North = progress.path_vector[0];
velocityDesired.East = progress.path_vector[1];
velocityDesired.Down = progress.path_vector[2];
if (limited &&
// if a plane is crossing its desired flightpath facing the wrong way (away from flight direction)
@ -629,39 +600,27 @@ static void updatePathVelocity(float kFF, float kH, float kV, bool limited)
// difference between path_direction and velocitystate >90 degrees ( 4th sector, facing away from everything )
// fix: ignore correction, steer in path direction until the situation has become better (condition doesn't apply anymore)
// calculating angles < 90 degrees through dot products
((progress.path_direction[0] * velocityState.North + progress.path_direction[1] * velocityState.East + progress.path_direction[2] * velocityState.Down) < 0.0f) &&
((progress.correction_direction[0] * velocityState.North + progress.correction_direction[1] * velocityState.East + progress.correction_direction[2] * velocityState.Down) < 0.0f)) {
error_speed_horizontal = 0.0f;
error_speed_vertical = 0.0f;
}
// calculate correction - can also be zero if correction vector is 0 or no error present
velocityDesired.North += progress.correction_direction[0] * error_speed_horizontal;
velocityDesired.East += progress.correction_direction[1] * error_speed_horizontal;
velocityDesired.Down += progress.correction_direction[2] * error_speed_vertical;
// scale to correct length
float l = sqrtf(velocityDesired.North * velocityDesired.North + velocityDesired.East * velocityDesired.East + velocityDesired.Down * velocityDesired.Down);
if (l > 1e-9f) {
velocityDesired.North *= groundspeed / l;
velocityDesired.East *= groundspeed / l;
velocityDesired.Down *= groundspeed / l;
(vector_lengthf(progress.path_vector, 2) > 1e-6f) &&
((progress.path_vector[0] * velocityState.North + progress.path_vector[1] * velocityState.East) < 0.0f) &&
((progress.correction_vector[0] * velocityState.North + progress.correction_vector[1] * velocityState.East) < 0.0f)) {
;
} else {
velocityDesired.North = 0.0f;
velocityDesired.East = 0.0f;
velocityDesired.Down = 0.0f;
// calculate correction
velocityDesired.North += progress.correction_vector[0] * kH;
velocityDesired.East += progress.correction_vector[1] * kH;
}
velocityDesired.Down += progress.correction_vector[2] * kV;
// update pathstatus
pathStatus.error = progress.error;
pathStatus.error = progress.error;
pathStatus.fractional_progress = progress.fractional_progress;
pathStatus.path_direction_north = progress.path_direction[0];
pathStatus.path_direction_east = progress.path_direction[1];
pathStatus.path_direction_down = progress.path_direction[2];
pathStatus.path_direction_north = progress.path_vector[0];
pathStatus.path_direction_east = progress.path_vector[1];
pathStatus.path_direction_down = progress.path_vector[2];
pathStatus.correction_direction_north = progress.correction_direction[0];
pathStatus.correction_direction_east = progress.correction_direction[1];
pathStatus.correction_direction_down = progress.correction_direction[2];
pathStatus.correction_direction_north = progress.correction_vector[0];
pathStatus.correction_direction_east = progress.correction_vector[1];
pathStatus.correction_direction_down = progress.correction_vector[2];
VelocityDesiredSet(&velocityDesired);
}

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@ -525,9 +525,8 @@ static uint8_t conditionLegRemaining()
float cur[3] = { positionState.North, positionState.East, positionState.Down };
struct path_status progress;
path_progress(cast_struct_to_array(pathDesired.Start, pathDesired.Start.North),
cast_struct_to_array(pathDesired.End, pathDesired.End.North),
cur, &progress, pathDesired.Mode);
path_progress(&pathDesired,
cur, &progress);
if (progress.fractional_progress >= 1.0f - pathAction.ConditionParameters[0]) {
return true;
}
@ -550,9 +549,8 @@ static uint8_t conditionBelowError()
float cur[3] = { positionState.North, positionState.East, positionState.Down };
struct path_status progress;
path_progress(cast_struct_to_array(pathDesired.Start, pathDesired.Start.North),
cast_struct_to_array(pathDesired.End, pathDesired.End.North),
cur, &progress, pathDesired.Mode);
path_progress(&pathDesired,
cur, &progress);
if (progress.error <= pathAction.ConditionParameters[0]) {
return true;
}

View File

@ -114,8 +114,6 @@
<field name="PositionHoldOffset" units="m" type="float" elementnames="Horizontal,Vertical" defaultvalue="10,2"/>
<!-- optimized for current vtolpathfollower,
for fixed wing pathfollower set to Horizontal=500,Vertical=5 -->
<field name="PositionHoldStartingVelocity" units="m/s" type="float" elements="1" defaultvalue="20"/>
<!-- currently ignored by vtolpathfollower -->
<access gcs="readwrite" flight="readwrite"/>
<telemetrygcs acked="true" updatemode="onchange" period="0"/>
<telemetryflight acked="true" updatemode="onchange" period="0"/>