Difference between revisions of "Control Loops"

From PaparazziUAV
Jump to navigation Jump to search
Line 61: Line 61:
== Control loops using Airspeed Sensor ==
== Control loops using Airspeed Sensor ==


The control loops using an airspeed sensor are described [[Airspeed_sensor|here]].
Adding an airspeed sensor measures actual airspeed resulting in better throttle control and aircraft performance especially in windy conditions. The control loops using an airspeed sensor are described [[Airspeed_sensor|here]].


= Multi-rotor (Booz) autopilot =
= Multi-rotor (Booz) autopilot =

Revision as of 05:28, 11 October 2010

This page presents the default control loops used by the Paparazzi airborne code for navigation, guidance and control.

General Information

All the possible combinations of control loops might not be fully detailed.

In the following diagrams, the block s is used for the derivative function and 1/s is used for the integrator function.

The variables' names are the one used in the airborne code (written in C). Most of this name can the used capitalized in the Airframe Configuration file in order to define the default value of these variables. If in capital letters in the diagrams, the value is fixed and cannot be changed using Settings mechanism.

Fixed-wing autopilot

Global view

General overview

The elements servos, rc_commands, commands and command_laws correspond to specific section of the Airframe Configuration file. Most of the code located in these blocks is generated from the xml of th configuration file.

The value +/-9600 correspond to +/-MAX_PPRZ. This pprz unit is used as a normalized internal unit for input and output values of the control_laws block.

Navigation loop

The navigation loop is located in sw/airborne/nav.*. The navigation routines are called from the Flight Plans.

Course loop

Course loop

The course loop is the upper stage of the horizontal control. It is located in sw/airborne/fw_h_ctl.c.

Roll loop

Roll loop

The roll loop is the lower stage of the horizontal control and is used for lateral attitude stabilization. It is located in sw/airborne/fw_h_ctl.c.

Altitude loop

Altitude loop

The altitude loop is the upper stage of the vertical control. It is located in sw/airborne/fw_v_ctl.c.

Auto Throttle and Auto Pitch climb loops

Two climb loops are available. The are called from the flight plan by changing the vertical navigation mode. The default mode is Auto Throttle.


Auto Throttle climb loop


Auto Pitch climb loop

The climb loop is the intermediate stage of the vertical control. It is located in sw/airborne/fw_v_ctl.c.

Pitch loop

Pitch loop

The pitch loop is the lower stage of the vertical control and is used for longitudinal attitude stabilization. It is located in sw/airborne/fw_h_ctl.c (!).

Control loops using Airspeed Sensor

Adding an airspeed sensor measures actual airspeed resulting in better throttle control and aircraft performance especially in windy conditions. The control loops using an airspeed sensor are described here.

Multi-rotor (Booz) autopilot