checked out attitude fw folder from master

attitude_fw/ecl_controller.h

@@ -75,6 +75,8 @@ struct ECL_ControlData {
 	float airspeed_max;
 	float airspeed;
 	float scaler;
+	float groundspeed;
+	float groundspeed_scaler;
 	bool lock_integrator;
 };
 

attitude_fw/ecl_wheel_controller.cpp

@@ -0,0 +1,153 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013 Estimation and Control Library (ECL). 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 ECL 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 ecl_wheel_controller.cpp
+ * Implementation of a simple PID wheel controller for heading tracking.
+ *
+ * Authors and acknowledgements in header.
+ */
+
+#include "ecl_wheel_controller.h"
+#include <stdint.h>
+#include <float.h>
+#include <geo/geo.h>
+#include <ecl/ecl.h>
+#include <mathlib/mathlib.h>
+#include <systemlib/err.h>
+#include <ecl/ecl.h>
+
+ECL_WheelController::ECL_WheelController() :
+    ECL_Controller("wheel")
+{
+}
+
+ECL_WheelController::~ECL_WheelController()
+{
+}
+
+float ECL_WheelController::control_bodyrate(const struct ECL_ControlData &ctl_data)
+{
+    /* Do not calculate control signal with bad inputs */
+    if (!(PX4_ISFINITE(ctl_data.yaw_rate) &&
+          PX4_ISFINITE(ctl_data.groundspeed) &&
+          PX4_ISFINITE(ctl_data.groundspeed_scaler))) {
+        perf_count(_nonfinite_input_perf);
+        return math::constrain(_last_output, -1.0f, 1.0f);
+    }
+
+    /* get the usual dt estimate */
+    uint64_t dt_micros = ecl_elapsed_time(&_last_run);
+    _last_run = ecl_absolute_time();
+    float dt = (float)dt_micros * 1e-6f;
+
+    /* lock integral for long intervals */
+    bool lock_integrator = ctl_data.lock_integrator;
+
+    if (dt_micros > 500000) {
+        lock_integrator = true;
+    }
+
+    /* input conditioning */
+    float min_speed = 1.0f;
+
+    /* Calculate body angular rate error */
+    _rate_error = _rate_setpoint - ctl_data.yaw_rate; //body angular rate error
+
+    if (!lock_integrator && _k_i > 0.0f && ctl_data.groundspeed > min_speed) {
+
+        float id = _rate_error * dt * ctl_data.groundspeed_scaler;
+
+        /*
+         * anti-windup: do not allow integrator to increase if actuator is at limit
+         */
+        if (_last_output < -1.0f) {
+            /* only allow motion to center: increase value */
+            id = math::max(id, 0.0f);
+
+        } else if (_last_output > 1.0f) {
+            /* only allow motion to center: decrease value */
+            id = math::min(id, 0.0f);
+        }
+
+        _integrator += id;
+    }
+
+    /* integrator limit */
+    //xxx: until start detection is available: integral part in control signal is limited here
+    float integrator_constrained = math::constrain(_integrator * _k_i, -_integrator_max, _integrator_max);
+
+    /* Apply PI rate controller and store non-limited output */
+    _last_output = _rate_setpoint * _k_ff * ctl_data.groundspeed_scaler +
+            _rate_error * _k_p * ctl_data.groundspeed_scaler * ctl_data.groundspeed_scaler +
+            integrator_constrained;
+    /*warnx("wheel: _last_output: %.4f, _integrator: %.4f, scaler %.4f",
+            (double)_last_output, (double)_integrator, (double)ctl_data.groundspeed_scaler);*/
+
+
+    return math::constrain(_last_output, -1.0f, 1.0f);
+}
+
+
+float ECL_WheelController::control_attitude(const struct ECL_ControlData &ctl_data)
+{
+    /* Do not calculate control signal with bad inputs */
+    if (!(PX4_ISFINITE(ctl_data.yaw_setpoint) &&
+          PX4_ISFINITE(ctl_data.yaw))) {
+        perf_count(_nonfinite_input_perf);
+        warnx("not controlling wheel");
+        return _rate_setpoint;
+    }
+
+    /* Calculate the error */
+    float yaw_error = ctl_data.yaw_setpoint - ctl_data.yaw;
+    /* shortest angle (wrap around) */
+    yaw_error = (float)fmod((float)fmod((yaw_error + M_PI_F), M_TWOPI_F) + M_TWOPI_F, M_TWOPI_F) - M_PI_F;
+    /*warnx("yaw_error: %.4f", (double)yaw_error);*/
+
+    /*  Apply P controller: rate setpoint from current error and time constant */
+    _rate_setpoint =  yaw_error / _tc;
+
+    /* limit the rate */
+    if (_max_rate > 0.01f) {
+        if (_rate_setpoint > 0.0f) {
+            _rate_setpoint = (_rate_setpoint > _max_rate) ? _max_rate : _rate_setpoint;
+
+        } else {
+            _rate_setpoint = (_rate_setpoint < -_max_rate) ? -_max_rate : _rate_setpoint;
+        }
+
+    }
+
+    return _rate_setpoint;
+}

attitude_fw/ecl_wheel_controller.h

@@ -0,0 +1,70 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2013 Estimation and Control Library (ECL). 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 ECL 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 ecl_wheel_controller.h
+ * Definition of a simple orthogonal coordinated turn yaw PID controller.
+ *
+ * @author Lorenz Meier <lm@inf.ethz.ch>
+ * @author Thomas Gubler <thomasgubler@gmail.com>
+ * @author Andreas Antener <andreas@uaventure.com>
+ *
+ * Acknowledgements:
+ *
+ *   The control design is based on a design
+ *   by Paul Riseborough and Andrew Tridgell, 2013,
+ *   which in turn is based on initial work of
+ *   Jonathan Challinger, 2012.
+ */
+#ifndef ECL_HEADING_CONTROLLER_H
+#define ECL_HEADING_CONTROLLER_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "ecl_controller.h"
+
+class __EXPORT ECL_WheelController :
+    public ECL_Controller
+{
+public:
+    ECL_WheelController();
+
+    ~ECL_WheelController();
+
+    float control_attitude(const struct ECL_ControlData &ctl_data);
+
+    float control_bodyrate(const struct ECL_ControlData &ctl_data);
+};
+
+#endif // ECL_HEADING_CONTROLLER_H

attitude_fw/ecl_yaw_controller.h

@@ -76,14 +76,15 @@ public:
 		_coordinated_method = coordinated_method;
 	}
 
-protected:
-	float _coordinated_min_speed;
-
 	enum {
 		COORD_METHOD_OPEN = 0,
-		COORD_METHOD_CLOSEACC = 1,
+		COORD_METHOD_CLOSEACC = 1
 	};
 
+protected:
+	float _coordinated_min_speed;
+	float _max_rate;
+
 	int32_t _coordinated_method;
 
 	float control_bodyrate_impl(const struct ECL_ControlData &ctl_data);