Theory of Operation - Revision history

Simmis: Added link to Youtube video explaining PID.

2016-04-15T18:51:11Z

Added link to Youtube video explaining PID.

← Older revision		Revision as of 12:51, 15 April 2016
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	See more on Wikipedia: [http://en.wikipedia.org/wiki/PID_controller PID Controller]		See more on Wikipedia: [http://en.wikipedia.org/wiki/PID_controller PID Controller]

			PID explained by RC Model Reviews: [https://youtu.be/0vqWyramGy8 What PIDs do and how they do it]

	Paparazzi uses PID controllers on all loops but many of the I and D terms are not fully implemented as they are often unnecessary or difficult to tune. Below are some examples of the PID implementations in Paparazzi. There is a [[Control Loops\|graphical description of the control loops]] as well.		Paparazzi uses PID controllers on all loops but many of the I and D terms are not fully implemented as they are often unnecessary or difficult to tune. Below are some examples of the PID implementations in Paparazzi. There is a [[Control Loops\|graphical description of the control loops]] as well.

Ghattenb at 11:07, 18 May 2012

2012-05-18T11:07:36Z

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   float v_ctl_pitch_of_vz <nowiki>=</nowiki> v_ctl_climb_setpoint * v_ctl_auto_throttle_pitch_of_vz_pgain;
 }}
 [[Category:Software]] [[Category:User_Documentation]]

Ijimenez: /* Climb Rate */

2012-04-02T15:25:09Z

Climb Rate

← Older revision		Revision as of 09:25, 2 April 2012
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	}}		}}
	Here we only use the Proportional term though a Derivative would be useful as climb rate is not well damped. An integral term may prove useful if well-implemented. The last term <b><tt>v_ctl_altitude_pre_climb</tt></b> represents the desired constant climb rate needed to follow a 3-dimensional navigation path. This term is zero for level flight, altitude maintenance, and commanded altitude changes.		Here we only use the Proportional term though a Derivative would be useful as climb rate is not well damped. An integral term may prove useful if well-implemented. The last term <b><tt>v_ctl_altitude_pre_climb</tt></b> represents the desired constant climb rate needed to follow a 3-dimensional navigation path. This term is zero for level flight, altitude maintenance, and commanded altitude changes.
	{{Box Code\| ~~\|In <b>sw/airborne/firmwares/fixedwing/guidance/guidance_v_n.c</b>~~ Then we compute the throttle response:\|		{{Box Code\| Then we compute the throttle response:\|
	float err <nowiki>=</nowiki> estimator_z_dot - v_ctl_climb_setpoint;		float err <nowiki>=</nowiki> estimator_z_dot - v_ctl_climb_setpoint;
	float controlled_throttle <nowiki>=</nowiki> v_ctl_auto_throttle_cruise_throttle + v_ctl_auto_throttle_climb_throttle_increment * v_ctl_climb_setpoint		float controlled_throttle <nowiki>=</nowiki> v_ctl_auto_throttle_cruise_throttle + v_ctl_auto_throttle_climb_throttle_increment * v_ctl_climb_setpoint

Ijimenez: /* Climb Rate */

2012-04-02T15:24:45Z

Climb Rate

← Older revision		Revision as of 09:24, 2 April 2012
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	}}		}}
	Here we only use the Proportional term though a Derivative would be useful as climb rate is not well damped. An integral term may prove useful if well-implemented. The last term <b><tt>v_ctl_altitude_pre_climb</tt></b> represents the desired constant climb rate needed to follow a 3-dimensional navigation path. This term is zero for level flight, altitude maintenance, and commanded altitude changes.		Here we only use the Proportional term though a Derivative would be useful as climb rate is not well damped. An integral term may prove useful if well-implemented. The last term <b><tt>v_ctl_altitude_pre_climb</tt></b> represents the desired constant climb rate needed to follow a 3-dimensional navigation path. This term is zero for level flight, altitude maintenance, and commanded altitude changes.
	{{Box Code\| Then we compute the throttle response:\|		{{Box Code\| \|In <b>sw/airborne/firmwares/fixedwing/guidance/guidance_v_n.c</b> Then we compute the throttle response:\|
	float err <nowiki>=</nowiki> estimator_z_dot - v_ctl_climb_setpoint;		float err <nowiki>=</nowiki> estimator_z_dot - v_ctl_climb_setpoint;
	float controlled_throttle <nowiki>=</nowiki> v_ctl_auto_throttle_cruise_throttle + v_ctl_auto_throttle_climb_throttle_increment * v_ctl_climb_setpoint		float controlled_throttle <nowiki>=</nowiki> v_ctl_auto_throttle_cruise_throttle + v_ctl_auto_throttle_climb_throttle_increment * v_ctl_climb_setpoint

Ijimenez: /* Climb Rate */

2012-04-02T15:24:15Z

Climb Rate

← Older revision		Revision as of 09:24, 2 April 2012
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	}}		}}
	Here we only use the Proportional term though a Derivative would be useful as climb rate is not well damped. An integral term may prove useful if well-implemented. The last term <b><tt>v_ctl_altitude_pre_climb</tt></b> represents the desired constant climb rate needed to follow a 3-dimensional navigation path. This term is zero for level flight, altitude maintenance, and commanded altitude changes.		Here we only use the Proportional term though a Derivative would be useful as climb rate is not well damped. An integral term may prove useful if well-implemented. The last term <b><tt>v_ctl_altitude_pre_climb</tt></b> represents the desired constant climb rate needed to follow a 3-dimensional navigation path. This term is zero for level flight, altitude maintenance, and commanded altitude changes.
	{{Box Code\|~~\|In <b>sw/airborne/firmwares/fixedwing/guidance/guidance_v_n.c</b>~~ Then we compute the throttle response:\|		{{Box Code\| Then we compute the throttle response:\|
	float err <nowiki>=</nowiki> estimator_z_dot - v_ctl_climb_setpoint;		float err <nowiki>=</nowiki> estimator_z_dot - v_ctl_climb_setpoint;
	float controlled_throttle <nowiki>=</nowiki> v_ctl_auto_throttle_cruise_throttle + v_ctl_auto_throttle_climb_throttle_increment * v_ctl_climb_setpoint		float controlled_throttle <nowiki>=</nowiki> v_ctl_auto_throttle_cruise_throttle + v_ctl_auto_throttle_climb_throttle_increment * v_ctl_climb_setpoint

Ijimenez: /* Climb Rate */

2012-04-02T15:23:52Z

Climb Rate

← Older revision		Revision as of 09:23, 2 April 2012
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	}}		}}
	Here we only use the Proportional term though a Derivative would be useful as climb rate is not well damped. An integral term may prove useful if well-implemented. The last term <b><tt>v_ctl_altitude_pre_climb</tt></b> represents the desired constant climb rate needed to follow a 3-dimensional navigation path. This term is zero for level flight, altitude maintenance, and commanded altitude changes.		Here we only use the Proportional term though a Derivative would be useful as climb rate is not well damped. An integral term may prove useful if well-implemented. The last term <b><tt>v_ctl_altitude_pre_climb</tt></b> represents the desired constant climb rate needed to follow a 3-dimensional navigation path. This term is zero for level flight, altitude maintenance, and commanded altitude changes.
	{{Box Code\|Then we compute the throttle response:\|		{{Box Code\|\|In <b>sw/airborne/firmwares/fixedwing/guidance/guidance_v_n.c</b> Then we compute the throttle response:\|
	float err <nowiki>=</nowiki> estimator_z_dot - v_ctl_climb_setpoint;		float err <nowiki>=</nowiki> estimator_z_dot - v_ctl_climb_setpoint;
	float controlled_throttle <nowiki>=</nowiki> v_ctl_auto_throttle_cruise_throttle + v_ctl_auto_throttle_climb_throttle_increment * v_ctl_climb_setpoint		float controlled_throttle <nowiki>=</nowiki> v_ctl_auto_throttle_cruise_throttle + v_ctl_auto_throttle_climb_throttle_increment * v_ctl_climb_setpoint

Ijimenez: /* Climb Rate */

2012-04-02T15:22:03Z

Climb Rate

← Older revision		Revision as of 09:22, 2 April 2012
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	=== Climb Rate ===		=== Climb Rate ===
	{{Box Code\|In <b>sw/airborne/~~fw_v_ctl~~.c</b> we compute the desired climb rate:\|		{{Box Code\|In <b>sw/airborne/firmwares/fixedwing/guidance/guidance_v_n.c</b> we compute the desired climb rate:\|
	v_ctl_altitude_error <nowiki>=</nowiki> estimator_z - v_ctl_altitude_setpoint;		v_ctl_altitude_error <nowiki>=</nowiki> estimator_z - v_ctl_altitude_setpoint;
	v_ctl_climb_setpoint <nowiki>=</nowiki> v_ctl_altitude_pgain * v_ctl_altitude_error + v_ctl_altitude_pre_climb;		v_ctl_climb_setpoint <nowiki>=</nowiki> v_ctl_altitude_pgain * v_ctl_altitude_error + v_ctl_altitude_pre_climb;

Ijimenez: /* Navigation */

2012-04-02T13:47:49Z

Navigation

← Older revision		Revision as of 07:47, 2 April 2012
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	=== Navigation ===		=== Navigation ===
	{{Box Code\|In <b>sw/airborne/~~fw_h_ctl~~.c</b> we define the navigation loop:\|		{{Box Code\|In <b>sw/airborne/firmwares/fixedwing/stabilization/stabilization_attitude.c</b> we define the navigation loop:\|
	float err <nowiki>=</nowiki> estimator_hspeed_dir - h_ctl_course_setpoint;		float err <nowiki>=</nowiki> estimator_hspeed_dir - h_ctl_course_setpoint;
	NormRadAngle(err);		NormRadAngle(err);

Ijimenez: /* Pitch Angle */

2012-04-02T13:33:30Z

Pitch Angle

← Older revision		Revision as of 07:33, 2 April 2012
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	=== Pitch Angle ===		=== Pitch Angle ===
	{{Box Code\|In <b>sw/airborne/~~fw_h_ctl~~.c</b> we define the pitch angle loop:\|		{{Box Code\|In <b>sw/airborne/firmwares/fixedwing/stabilization/stabilization_attitude.c</b> we define the pitch angle loop:\|
	float err <nowiki>=</nowiki> estimator_theta - h_ctl_pitch_setpoint;		float err <nowiki>=</nowiki> estimator_theta - h_ctl_pitch_setpoint;
	float d_err <nowiki>=</nowiki> err - last_err;		float d_err <nowiki>=</nowiki> err - last_err;

Ijimenez: /* Roll Attitude */

2012-04-02T13:30:29Z

Roll Attitude

← Older revision		Revision as of 07:30, 2 April 2012
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	=== Roll Attitude ===		=== Roll Attitude ===
	{{Box Code\|In <b>sw/airborne/~~fw_h_ctl~~.c</b> we define the roll attitude gain loop:\|		{{Box Code\|In <b>sw/airborne/firmwares/fixedwing/stabilization/stabilization_attitude.c</b> we define the roll attitude gain loop:\|
	float err <nowiki>=</nowiki> estimator_phi - h_ctl_roll_setpoint;		float err <nowiki>=</nowiki> estimator_phi - h_ctl_roll_setpoint;
	float cmd <nowiki>=</nowiki> - h_ctl_roll_attitude_gain * err- h_ctl_roll_rate_gain * estimator_p+ v_ctl_throttle_setpoint * h_ctl_aileron_of_throttle;		float cmd <nowiki>=</nowiki> - h_ctl_roll_attitude_gain * err- h_ctl_roll_rate_gain * estimator_p+ v_ctl_throttle_setpoint * h_ctl_aileron_of_throttle;
	}}		}}


	=== Pitch Angle ===		=== Pitch Angle ===