Example for airframe file

Add to your firmware section: This example contains all possible configuration options, not all of them are mandatory!

<module name="ground_detect">
  b'<define name="GROUND_DETECT_USE_INDI_THRUST" value="1" />\n    '
  b'<define name="GROUND_DETECT_SPECIFIC_THRUST_THRESHOLD" value="-5.0" />\n\n    '
  b'<define name="GROUND_DETECT_USE_AGL_DIST" value="0" />\n    '
  b'<define name="GROUND_DETECT_AGL_MIN_VALUE" value="0.1" />\n\n    '
  b'<define name="GROUND_DETECT_USE_FORCE_SENSOR" value="0" />\n    '
  b'<define name="GROUND_DETECT_FORCE_SENSOR_THRESHOLD" value="100000" />\n    '
  b'<define name="GROUND_DETECT_FORCE_SENSOR_MEDIAN_FILT_SIZE" value="3" />\n\n    '
  b'<define name="GROUND_DETECT_COUNTER_TRIGGER" value="10" />\n  '
</module>

Module configuration options

Define Options

name: GROUND_DETECT_USE_INDI_THRUST value: 1
Description: Use INDI thrust less than 50 percent as detection
name: GROUND_DETECT_SPECIFIC_THRUST_THRESHOLD value: -5.0
Description: [m/s2] positive down
name: GROUND_DETECT_USE_AGL_DIST value: 0
Description: Use agl_dist_filtered
name: GROUND_DETECT_AGL_MIN_VALUE value: 0.1
Description: AGL value low enough to be used as ground detection [m]
name: GROUND_DETECT_USE_FORCE_SENSOR value: 0
Description: Use FORCE_SENSOR ABI for ground detection
name: GROUND_DETECT_FORCE_SENSOR_THRESHOLD value: 100000
Description: Threshold on filtered force sensor value to detect ground
name: GROUND_DETECT_FORCE_SENSOR_MEDIAN_FILT_SIZE value: 3
Description: Median filter size for force sensor processing
name: GROUND_DETECT_COUNTER_TRIGGER value: 10
Description: Number of times a trigger must be valid to accept ground detection.

Module functions

Init Functions

These initialization functions are called once on startup.

ground_detect_init()

Periodic Functions

These functions are called periodically at the specified frequency from the module periodic loop.

ground_detect_periodic()
- Frequency in Hz: 50
- Autorun: LOCK
  Periodic function automatically starts after init and can't be stopped.
ground_detect_filter_accel()
- Running at maximum module frequency.
- Autorun: LOCK
  Periodic function automatically starts after init and can't be stopped.

Files

Header Files

The following headers are automatically included in modules.h

ground_detect.h

Source Files

modules/nav/ground_detect.c

Raw ground_detect.xml file:

<!DOCTYPE module SYSTEM "module.dtd">
<module name="ground_detect" dir="nav">
  <doc>
    <description>
      Ground detection module to detect ground.
    </description>
    <define name="GROUND_DETECT_USE_INDI_THRUST" value="1" description="Use INDI thrust less than 50 percent as detection"/>
    <define name="GROUND_DETECT_SPECIFIC_THRUST_THRESHOLD" value="-5.0" description="[m/s2] positive down"/>
 
    <define name="GROUND_DETECT_USE_AGL_DIST" value="0" description="Use agl_dist_filtered"/>
    <define name="GROUND_DETECT_AGL_MIN_VALUE" value="0.1" description="AGL value low enough to be used as ground detection [m]"/>
 
    <define name="GROUND_DETECT_USE_FORCE_SENSOR" value="0" description="Use FORCE_SENSOR ABI for ground detection"/>
    <define name="GROUND_DETECT_FORCE_SENSOR_THRESHOLD" value="100000" description="Threshold on filtered force sensor value to detect ground"/>
    <define name="GROUND_DETECT_FORCE_SENSOR_MEDIAN_FILT_SIZE" value="3" description="Median filter size for force sensor processing"/>
 
    <define name="GROUND_DETECT_COUNTER_TRIGGER" value="10" description="Number of times a trigger must be valid to accept ground detection."/>
  </doc>
  <settings>
    <dl_settings>
      <dl_settings name="Ground Detect">
        <dl_setting var="reverse_th_level" min="-9600" max="0" step="1" shortname="Reverse thrust level"/>
        <dl_setting var="set_offset_sensors" min="0" max="1" step="1" values="FALSE|TRUE" type="fun" handler="set_offset_sensors" module="modules/nav/ground_detect"/>
        <dl_setting var="force_sensor_ground_threshold" min="-1000000" max="1000000" step="1000" shortname="ground_threshold"/>
      </dl_settings>
    </dl_settings>
  </settings>
 
  <header>
    <file name="ground_detect.h"/>
  </header>
  <init fun="ground_detect_init()"/>
  <periodic fun="ground_detect_periodic()" freq="50"/>
  <periodic fun="ground_detect_filter_accel()"/>
  <makefile>
    <file name="ground_detect.c"/>
    <test firmware="rotorcraft">
      <define name="PERIODIC_FREQUENCY" value="512"/>
      <define name="GROUND_DETECT_USE_INDI_THRUST" value="1"/>
      <define name="DOWNLINK_TRANSPORT" value="pprz_tp"/>
      <define name="DOWNLINK_DEVICE" value="uart0"/>
      <define name="USE_UART0"/>
      <define name="INDI_OUTPUTS" value="1"/>
      <define name="INDI_NUM_ACT" value="1"/>
    </test>
  </makefile>
</module>