flight_mode_manager: merge with flight_tasks

src/modules/flight_mode_manager/tasks/AutoLineSmoothVel/TrajectoryConstraints.hpp

@@ -0,0 +1,180 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2019 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+#pragma once
+
+#include <px4_defines.h>
+
+#include <matrix/math.hpp>
+#include <mathlib/mathlib.h>
+
+namespace math
+{
+namespace trajectory
+{
+using matrix::Vector3f;
+using matrix::Vector2f;
+
+struct VehicleDynamicLimits {
+	float z_accept_rad;
+	float xy_accept_rad;
+
+	float max_acc_xy;
+	float max_jerk;
+
+	float max_speed_xy;
+
+	// TODO: remove this
+	float max_acc_xy_radius_scale;
+};
+
+/*
+ * Compute the maximum allowed speed at the waypoint assuming that we want to
+ * connect the two lines (current-target and target-next)
+ * with a tangent circle with constant speed and desired centripetal acceleration: a_centripetal = speed^2 / radius
+ * The circle should in theory start and end at the intersection of the lines and the waypoint's acceptance radius.
+ * This is not exactly true in reality since Navigator switches the waypoint so we have to take in account that
+ * the real acceptance radius is smaller.
+ *
+ */
+inline float computeStartXYSpeedFromWaypoints(const Vector3f &start_position, const Vector3f &target,
+		const Vector3f &next_target, float exit_speed, const VehicleDynamicLimits &config)
+{
+	const float distance_target_next = (target - next_target).xy().norm();
+
+	const bool target_next_different = distance_target_next  > 0.001f;
+	const bool waypoint_overlap = distance_target_next < config.xy_accept_rad;
+	const bool has_reached_altitude = fabsf(target(2) - start_position(2)) < config.z_accept_rad;
+	const bool altitude_stays_same = fabsf(next_target(2) - target(2)) < config.z_accept_rad;
+
+	float speed_at_target = 0.0f;
+
+	if (target_next_different &&
+	    !waypoint_overlap &&
+	    has_reached_altitude &&
+	    altitude_stays_same
+	   ) {
+		const float alpha = acosf(Vector2f((target - start_position).xy()).unit_or_zero().dot(
+						  Vector2f((target - next_target).xy()).unit_or_zero()));
+		const float safe_alpha = constrain(alpha, 0.f, M_PI_F - FLT_EPSILON);
+		float accel_tmp = config.max_acc_xy_radius_scale * config.max_acc_xy;
+		float max_speed_in_turn = computeMaxSpeedInWaypoint(safe_alpha, accel_tmp, config.xy_accept_rad);
+		speed_at_target = min(min(max_speed_in_turn, exit_speed), config.max_speed_xy);
+	}
+
+	float start_to_target = (start_position - target).xy().norm();
+	float max_speed = computeMaxSpeedFromDistance(config.max_jerk, config.max_acc_xy, start_to_target, speed_at_target);
+
+	return min(config.max_speed_xy, max_speed);
+}
+
+/*
+ * This function computes the maximum speed XY that can be travelled, given a set of waypoints and vehicle dynamics
+ *
+ * The first waypoint should be the starting location, and the later waypoints the desired points to be followed.
+ *
+ * @param waypoints the list of waypoints to be followed, the first of which should be the starting location
+ * @param config the vehicle dynamic limits
+ *
+ * @return the maximum speed at waypoint[0] which allows it to follow the trajectory while respecting the dynamic limits
+ */
+template <size_t N>
+float computeXYSpeedFromWaypoints(const Vector3f waypoints[N], const VehicleDynamicLimits &config)
+{
+	static_assert(N >= 2, "Need at least 2 points to compute speed");
+
+	float max_speed = 0.f;
+
+	for (size_t j = 0; j < N - 1; j++) {
+		size_t i = N - 2 - j;
+		max_speed = computeStartXYSpeedFromWaypoints(waypoints[i],
+				waypoints[i + 1],
+				waypoints[min(i + 2, N - 1)],
+				max_speed, config);
+	}
+
+	return max_speed;
+}
+
+/*
+ * Constrain the 3D vector given a maximum XY norm
+ * If the XY norm of the 3D vector is larger than the maximum norm, the whole vector
+ * is scaled down to respect the constraint.
+ * If the maximum norm is small (defined by the "accuracy" parameter),
+ * only the XY components are scaled down to avoid affecting
+ * Z in case of numerical issues
+ */
+inline void clampToXYNorm(Vector3f &target, float max_xy_norm, float accuracy = FLT_EPSILON)
+{
+	const float xynorm = target.xy().norm();
+	const float scale_factor = (xynorm > FLT_EPSILON)
+				   ? max_xy_norm / xynorm
+				   : 1.f;
+
+	if (scale_factor < 1.f) {
+		if (max_xy_norm < accuracy && xynorm < accuracy) {
+			target.xy() = Vector2f(target) * scale_factor;
+
+		} else {
+			target *= scale_factor;
+		}
+	}
+}
+
+/*
+ * Constrain the 3D vector given a maximum Z norm
+ * If the Z component of the 3D vector is larger than the maximum norm, the whole vector
+ * is scaled down to respect the constraint.
+ * If the maximum norm is small (defined by the "accuracy parameter),
+ * only the Z component is scaled down to avoid affecting
+ * XY in case of numerical issues
+ */
+inline void clampToZNorm(Vector3f &target, float max_z_norm, float accuracy = FLT_EPSILON)
+{
+	const float znorm = fabs(target(2));
+	const float scale_factor = (znorm > FLT_EPSILON)
+				   ? max_z_norm / znorm
+				   : 1.f;
+
+	if (scale_factor < 1.f) {
+		if (max_z_norm < accuracy && znorm < accuracy) {
+			target(2) *= scale_factor;
+
+		} else {
+			target *= scale_factor;
+		}
+	}
+}
+
+}
+}