Reworking control infrastructure for inner rate loop, preparing offboard interface

1 files changed, 256 insertions, 0 deletions

diff --git a/apps/multirotor_att_control/multirotor_rate_control.c b/apps/multirotor_att_control/multirotor_rate_control.c
new file mode 100644
index 000000000..8a3ac78cd
--- /dev/null
+++ b/apps/multirotor_att_control/multirotor_rate_control.c
@@ -0,0 +1,256 @@
+/****************************************************************************
+ *
+ *   Copyright (C) 2012 PX4 Development Team. All rights reserved.
+ *   Author: @author Tobias Naegeli <naegelit@student.ethz.ch>
+ *           @author Lorenz Meier <lm@inf.ethz.ch>
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+/**
+ * @file multirotor_rate_control.c
+ * Implementation of rate controller
+ */
+
+#include "multirotor_rate_control.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <float.h>
+#include <math.h>
+#include <systemlib/pid/pid.h>
+#include <systemlib/param/param.h>
+#include <arch/board/up_hrt.h>
+
+// PARAM_DEFINE_FLOAT(MC_YAWRATE_P, 0.08f); /* same on Flamewheel */
+// PARAM_DEFINE_FLOAT(MC_YAWRATE_I, 0.02f);
+// PARAM_DEFINE_FLOAT(MC_YAWRATE_AWU, 0.02f);
+// PARAM_DEFINE_FLOAT(MC_YAWRATE_LIM, 0.1f);
+
+PARAM_DEFINE_FLOAT(MC_ATTRATE_P, 0.2f); /* 0.15 F405 Flamewheel */
+PARAM_DEFINE_FLOAT(MC_ATTRATE_I, 0.0f);
+PARAM_DEFINE_FLOAT(MC_ATTRATE_AWU, 0.05f);
+PARAM_DEFINE_FLOAT(MC_ATTRATE_LIM, 8.0f);	/**< roughly < 500 deg/s limit */
+
+struct mc_rate_control_params {
+
+	float yawrate_p;
+	float yawrate_i;
+	float yawrate_awu;
+	float yawrate_lim;
+
+	float attrate_p;
+	float attrate_i;
+	float attrate_awu;
+	float attrate_lim;
+
+	float rate_lim;
+};
+
+struct mc_rate_control_param_handles {
+
+	param_t yawrate_p;
+	param_t yawrate_i;
+	param_t yawrate_awu;
+	param_t yawrate_lim;
+
+	param_t attrate_p;
+	param_t attrate_i;
+	param_t attrate_awu;
+	param_t attrate_lim;
+};
+
+/**
+ * Initialize all parameter handles and values
+ *
+ */
+static int parameters_init(struct mc_rate_control_param_handles *h);
+
+/**
+ * Update all parameters
+ *
+ */
+static int parameters_update(const struct mc_rate_control_param_handles *h, struct mc_rate_control_params *p);
+
+
+static int parameters_init(struct mc_rate_control_param_handles *h)
+{
+	/* PID parameters */
+	h->yawrate_p 	=	param_find("MC_YAWRATE_P");
+	h->yawrate_i 	=	param_find("MC_YAWRATE_I");
+	h->yawrate_awu 	=	param_find("MC_YAWRATE_AWU");
+	h->yawrate_lim 	=	param_find("MC_YAWRATE_LIM");
+
+	h->attrate_p 	= 	param_find("MC_ATTRATE_P");
+	h->attrate_i 	= 	param_find("MC_ATTRATE_I");
+	h->attrate_awu 	= 	param_find("MC_ATTRATE_AWU");
+	h->attrate_lim 	= 	param_find("MC_ATTRATE_LIM");
+
+	return OK;
+}
+
+static int parameters_update(const struct mc_rate_control_param_handles *h, struct mc_rate_control_params *p)
+{
+	param_get(h->yawrate_p, &(p->yawrate_p));
+	param_get(h->yawrate_i, &(p->yawrate_i));
+	param_get(h->yawrate_awu, &(p->yawrate_awu));
+	param_get(h->yawrate_lim, &(p->yawrate_lim));
+
+	param_get(h->attrate_p, &(p->attrate_p));
+	param_get(h->attrate_i, &(p->attrate_i));
+	param_get(h->attrate_awu, &(p->attrate_awu));
+	param_get(h->attrate_lim, &(p->attrate_lim));
+
+	return OK;
+}
+
+void multirotor_control_rates(const struct vehicle_attitude_setpoint_s *rate_sp,
+	const float rates[], struct actuator_controls_s *actuators)
+{
+	static uint64_t last_run = 0;
+	const float deltaT = (hrt_absolute_time() - last_run) / 1000000.0f;
+	last_run = hrt_absolute_time();
+
+	static int motor_skip_counter = 0;
+
+	// static PID_t yaw_pos_controller;
+	static PID_t yaw_speed_controller;
+	static PID_t pitch_controller;
+	static PID_t roll_controller;
+
+	static struct mc_rate_control_params p;
+	static struct mc_rate_control_param_handles h;
+
+	static bool initialized = false;
+
+	/* initialize the pid controllers when the function is called for the first time */
+	if (initialized == false) {
+		parameters_init(&h);
+		parameters_update(&h, &p);
+
+		pid_init(&yaw_speed_controller, p.yawrate_p, 0, p.yawrate_i, p.yawrate_awu,
+			PID_MODE_DERIVATIV_SET, 155);
+		pid_init(&pitch_controller, p.attrate_p, p.attrate_i, 0, p.attrate_awu,
+			PID_MODE_DERIVATIV_SET, 156);
+		pid_init(&roll_controller, p.attrate_p, p.attrate_i, 0, p.attrate_awu,
+			PID_MODE_DERIVATIV_SET, 157);
+
+		initialized = true;
+	}
+
+	/* load new parameters with lower rate */
+	if (motor_skip_counter % 250 == 0) {
+		/* update parameters from storage */
+		parameters_update(&h, &p);
+		/* apply parameters */
+		pid_set_parameters(&yaw_speed_controller, p.yawrate_p, p.yawrate_i, 0, p.yawrate_awu);
+		pid_set_parameters(&pitch_controller, p.attrate_p, p.attrate_i, 0, p.attrate_awu);
+		pid_set_parameters(&roll_controller, p.attrate_p, p.attrate_i, 0, p.attrate_awu);
+	}
+
+	/* calculate current control outputs */
+	
+	/* control pitch (forward) output */
+	float pitch_control = pid_calculate(&pitch_controller, rate_sp->pitch_rate_body,
+					rates[1], 0.0f, deltaT);
+	/* control roll (left/right) output */
+	float roll_control = pid_calculate(&roll_controller, rate_sp->roll_rate_body,
+					rates[0], 0.0f, deltaT);
+	/* control yaw rate */
+	float yaw_rate_control = pid_calculate(&yaw_speed_controller, rate_sp->yaw_rate_body, rates[2], 0.0f, deltaT);
+
+	/*
+	 * compensate the vertical loss of thrust
+	 * when thrust plane has an angle.
+	 * start with a factor of 1.0 (no change)
+	 */
+	float zcompensation = 1.0f;
+
+	// if (fabsf(att->roll) > 0.3f) {
+	// 	zcompensation *= 1.04675160154f;
+
+	// } else {
+	// 	zcompensation *= 1.0f / cosf(att->roll);
+	// }
+
+	// if (fabsf(att->pitch) > 0.3f) {
+	// 	zcompensation *= 1.04675160154f;
+
+	// } else {
+	// 	zcompensation *= 1.0f / cosf(att->pitch);
+	// }
+
+	float motor_thrust = 0.0f;
+
+	motor_thrust = rate_sp->thrust;
+
+	/* compensate thrust vector for roll / pitch contributions */
+	motor_thrust *= zcompensation;
+
+	/* limit yaw rate output */
+	if (yaw_rate_control > p.yawrate_lim) {
+		yaw_rate_control = p.yawrate_lim;
+		yaw_speed_controller.saturated = 1;
+	}
+
+	if (yaw_rate_control < -p.yawrate_lim) {
+		yaw_rate_control = -p.yawrate_lim;
+		yaw_speed_controller.saturated = 1;
+	}
+
+	if (pitch_control > p.attrate_lim) {
+		pitch_control = p.attrate_lim;
+		pitch_controller.saturated = 1;
+	}
+
+	if (pitch_control < -p.attrate_lim) {
+		pitch_control = -p.attrate_lim;
+		pitch_controller.saturated = 1;
+	}
+
+
+	if (roll_control > p.attrate_lim) {
+		roll_control = p.attrate_lim;
+		roll_controller.saturated = 1;
+	}
+
+	if (roll_control < -p.attrate_lim) {
+		roll_control = -p.attrate_lim;
+		roll_controller.saturated = 1;
+	}
+
+	actuators->control[0] = roll_control;
+	actuators->control[1] = pitch_control;
+	actuators->control[2] = yaw_rate_control;
+	actuators->control[3] = motor_thrust;
+
+	motor_skip_counter++;
+}