From 66a1ae97044853f603e216e343b5d987208ed246 Mon Sep 17 00:00:00 2001 From: gguidone Date: Wed, 15 Apr 2026 11:18:21 +0200 Subject: [PATCH] docs: add parachute health failsafe documentation Update safety.md, peripherals/parachute.md, and releases/main.md to document the extended COM_PARACHUTE parameter and the new configurable in-flight failsafe behaviour. --- docs/en/config/safety.md | 13 +++++++++++++ docs/en/peripherals/parachute.md | 3 ++- docs/en/releases/main.md | 1 + 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/docs/en/config/safety.md b/docs/en/config/safety.md index 80c47833a5..9171260685 100644 --- a/docs/en/config/safety.md +++ b/docs/en/config/safety.md @@ -280,6 +280,19 @@ The failsafe action and arming behaviour are both configured by the `COM_ARM_ODI | ----------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [COM_ARM_ODID](../advanced_config/parameter_reference.md#COM_ARM_ODID) | Remote ID arming check and in-flight failsafe. `0`: Disabled (default), `1`: Warning only, `2`: Error only (prevents arming), `3`: Return, `4`: Land, `5`: Terminate.

On failsafe:
- `Error`, `Return`, `Land` and `Terminate` prevent arming.
- `Return`, `Land` and `Terminate` start the associated action/mode when airborne. | +## Parachute Health Failsafe + + + +The parachute health failsafe is triggered when a [MAVLink parachute](../peripherals/parachute.md) system is missing or unhealthy while the vehicle is armed and airborne. + +| Parameter | Description | +| -------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- | +| [COM_PARACHUTE](../advanced_config/parameter_reference.md#COM_PARACHUTE) | Parachute system monitoring and failsafe action. `0`: Disabled (default), `1`: Warning only, `2`: Error only, `3`: Return, `4`: Land. | + +Values `2`–`4` prevent arming when the parachute system is not present and healthy. +Values `3`–`4` also trigger the configured failsafe action if the parachute system is missing or unhealthy while airborne. + ## Quad-chute Failsafe Failsafe for when a VTOL vehicle can no longer fly in fixed-wing mode, perhaps due to the failure of a pusher motor, airspeed sensor, or control surface. diff --git a/docs/en/peripherals/parachute.md b/docs/en/peripherals/parachute.md index 9487d8e3a1..6e8572a738 100644 --- a/docs/en/peripherals/parachute.md +++ b/docs/en/peripherals/parachute.md @@ -74,7 +74,8 @@ You then need to ensure that the parachute pin will be set to a value that will PX4 will trigger a connected and healthy parachute on failsafe by sending the command [MAV_CMD_DO_PARACHUTE](https://mavlink.io/en/messages/common.html#MAV_CMD_DO_PARACHUTE) with the [PARACHUTE_RELEASE](https://mavlink.io/en/messages/common.html#PARACHUTE_ACTION) action. -MAVLink parachute support is enabled by setting the parameter [COM_PARACHUTE=1](../advanced_config/parameter_reference.md#COM_PARACHUTE). +MAVLink parachute support is enabled by setting the parameter [COM_PARACHUTE](../advanced_config/parameter_reference.md#COM_PARACHUTE) to a non-zero value. +The parameter also configures the arming check and in-flight failsafe action when the parachute system is missing or unhealthy (see [Parachute Health Failsafe](../config/safety.md#parachute-health-failsafe)). PX4 will then indicate parachute status using the [MAV_SYS_STATUS_RECOVERY_SYSTEM](https://mavlink.io/en/messages/common.html#MAV_SYS_STATUS_RECOVERY_SYSTEM) bit in the [SYS_STATUS](https://mavlink.io/en/messages/common.html#SYS_STATUS) extended onboard control sensors fields: - `SYS_STATUS.onboard_control_sensors_present_extended`: MAVLink parachute present (based on heartbeat detection). diff --git a/docs/en/releases/main.md b/docs/en/releases/main.md index e55f0158bb..1ae7f524e0 100644 --- a/docs/en/releases/main.md +++ b/docs/en/releases/main.md @@ -44,6 +44,7 @@ Please continue reading for [upgrade instructions](#upgrade-guide). - [Remote ID (Open Drone ID) in-flight failsafe](../peripherals/remote_id.md): extended [COM_ARM_ODID](../advanced_config/parameter_reference.md#COM_ARM_ODID) to also trigger a configurable failsafe action (Return, Land, or Terminate) if the Remote ID heartbeat is lost while airborne. Users previously on `COM_ARM_ODID=2` retain the same arming behaviour; set to `3` or higher to enable the in-flight action. ([PX4-Autopilot#27029](https://github.com/PX4/PX4-Autopilot/pull/27029)) - [QGroundControl Bootloader Update](../advanced_config/bootloader_update.md#qgc-bootloader-update-sys-bl-update) via the [SYS_BL_UPDATE](../advanced_config/parameter_reference.md#SYS_BL_UPDATE) parameter has been re-enabled after being broken for a number of releases. ([PX4-Autopilot#25032: build: romf: fix generation of rc.board_bootloader_upgrade](https://github.com/PX4/PX4-Autopilot/pull/25032)). - [Feature: Allow prioritization of manual control inputs based on their instance number in ascending or descending order](../config/manual_control.md#px4-configuration). ([PX4-Autopilot#25602: Ascending and descending manual control input priorities](https://github.com/PX4/PX4-Autopilot/pull/25602)). +- [Parachute health failsafe](../peripherals/parachute.md): extended [COM_PARACHUTE](../advanced_config/parameter_reference.md#COM_PARACHUTE) from a boolean into a configurable failsafe parameter. The in-flight action is now selectable (Return or Land). Users previously on `COM_PARACHUTE=1` (block arming) must update to `2` to retain that behaviour; set to `3` or higher to also enable the in-flight failsafe action. ([PX4-Autopilot#26918](https://github.com/PX4/PX4-Autopilot/pull/26918)) ### Control