mode: control auto set home from an external mode

The mode executor can run land mode which updates the home position to the landing location. This
can be not the desirable behavior and the home position should stay at the original location.

A flag is added to the configuration overrides to control if the home position is updated or not.

Author: eyeam3

msg/px4_msgs_old/msg/ConfigOverridesV0.msg

@@ -0,0 +1,21 @@
+# Configurable overrides by (external) modes or mode executors
+
+uint32 MESSAGE_VERSION = 0
+
+uint64 timestamp		# time since system start (microseconds)
+
+bool disable_auto_disarm         # Prevent the drone from automatically disarming after landing (if configured)
+
+bool defer_failsafes             # Defer all failsafes that can be deferred (until the flag is cleared)
+int16 defer_failsafes_timeout_s  # Maximum time a failsafe can be deferred. 0 = system default, -1 = no timeout
+
+
+int8 SOURCE_TYPE_MODE = 0
+int8 SOURCE_TYPE_MODE_EXECUTOR = 1
+int8 source_type
+
+uint8 source_id                  # ID depending on source_type
+
+uint8 ORB_QUEUE_LENGTH = 4
+
+# TOPICS config_overrides config_overrides_request

msg/translation_node/translations/all_translations.h

@@ -10,6 +10,7 @@
 #include "translation_arming_check_reply_v1.h"
 #include "translation_arming_check_request_v1.h"
 #include "translation_battery_status_v1.h"
+#include "translation_config_overrides_v1.h"
 #include "translation_event_v1.h"
 #include "translation_home_position_v1.h"
 #include "translation_register_ext_component_reply_v1.h"

msg/translation_node/translations/translation_config_overrides_v1.h

@@ -0,0 +1,41 @@
+/****************************************************************************
+ * Copyright (c) 2025 PX4 Development Team.
+ * SPDX-License-Identifier: BSD-3-Clause
+ ****************************************************************************/
+#pragma once
+
+// Translate ConfigOverrides v0 <--> v1
+#include <px4_msgs_old/msg/config_overrides_v0.hpp>
+#include <px4_msgs/msg/config_overrides.hpp>
+
+class ConfigOverridesV1Translation {
+public:
+	using MessageOlder = px4_msgs_old::msg::ConfigOverridesV0;
+	static_assert(MessageOlder::MESSAGE_VERSION == 0);
+
+	using MessageNewer = px4_msgs::msg::ConfigOverrides;
+	static_assert(MessageNewer::MESSAGE_VERSION == 1);
+
+	static constexpr const char* kTopic = "fmu/in/config_overrides_request";
+
+	static void fromOlder(const MessageOlder &msg_older, MessageNewer &msg_newer) {
+		msg_newer.timestamp = msg_older.timestamp;
+		msg_newer.disable_auto_disarm = msg_older.disable_auto_disarm;
+		msg_newer.defer_failsafes = msg_older.defer_failsafes;
+		msg_newer.defer_failsafes_timeout_s = msg_older.defer_failsafes_timeout_s;
+		msg_newer.disable_auto_set_home = false;
+		msg_newer.source_type = msg_older.source_type;
+		msg_newer.source_id = msg_older.source_id;
+	}
+
+	static void toOlder(const MessageNewer &msg_newer, MessageOlder &msg_older) {
+		msg_older.timestamp = msg_newer.timestamp;
+		msg_older.disable_auto_disarm = msg_newer.disable_auto_disarm;
+		msg_older.defer_failsafes = msg_newer.defer_failsafes;
+		msg_older.defer_failsafes_timeout_s = msg_newer.defer_failsafes_timeout_s;
+		msg_older.source_type = msg_newer.source_type;
+		msg_older.source_id = msg_newer.source_id;
+	}
+};
+
+REGISTER_TOPIC_TRANSLATION_DIRECT(ConfigOverridesV1Translation);

msg/versioned/ConfigOverrides.msg

@@ -1,14 +1,14 @@
 # Configurable overrides by (external) modes or mode executors
 
-uint32 MESSAGE_VERSION = 0
+uint32 MESSAGE_VERSION = 1
 
 uint64 timestamp		# time since system start (microseconds)
 
 bool disable_auto_disarm         # Prevent the drone from automatically disarming after landing (if configured)
 
 bool defer_failsafes             # Defer all failsafes that can be deferred (until the flag is cleared)
 int16 defer_failsafes_timeout_s  # Maximum time a failsafe can be deferred. 0 = system default, -1 = no timeout
-
+bool disable_auto_set_home       # Prevent the drone from automatically setting the home position on arm or takeoff
 
 int8 SOURCE_TYPE_MODE = 0
 int8 SOURCE_TYPE_MODE_EXECUTOR = 1

src/modules/commander/Commander.cpp

@@ -638,7 +638,7 @@ transition_result_t Commander::arm(arm_disarm_reason_t calling_reason, bool run_
 	events::send<events::px4::enums::arm_disarm_reason_t>(events::ID("commander_armed_by"), events::Log::Info,
 			"Armed by {1}", calling_reason);
 
-	if (_param_com_home_en.get() && !_mission_in_progress) {
+	if (_param_com_home_en.get() && !_mission_in_progress && !_config_overrides.disable_auto_set_home) {
 		_home_position.setHomePosition();
 	}
 
@@ -1850,7 +1850,8 @@ void Commander::run()
 		_mission_in_progress = (_vehicle_status.nav_state == vehicle_status_s::NAVIGATION_STATE_AUTO_MISSION)
 				       && !_mission_result_sub.get().finished;
 
-		_home_position.update(_param_com_home_en.get(), !isArmed() && _vehicle_land_detected.landed && !_mission_in_progress);
+		_home_position.update(_param_com_home_en.get(), !isArmed() && _vehicle_land_detected.landed && !_mission_in_progress
+				      && !_config_overrides.disable_auto_set_home);
 
 		handleAutoDisarm();
 
@@ -2140,7 +2141,7 @@ void Commander::landDetectorUpdate()
 			}
 
 			// automatically set or update home position
-			if (_param_com_home_en.get() && !_mission_in_progress) {
+			if (_param_com_home_en.get() && !_mission_in_progress && !_config_overrides.disable_auto_set_home) {
 				// set the home position when taking off
 				if (!_vehicle_land_detected.landed) {
 					if (was_landed) {

src/modules/commander/ModeManagement.cpp

@@ -563,6 +563,10 @@ void ModeManagement::updateActiveConfigOverrides(uint8_t nav_state, config_overr
 			current_overrides.disable_auto_disarm = true;
 		}
 
+		if (executor_overrides.disable_auto_set_home) {
+			current_overrides.disable_auto_set_home = true;
+		}
+
 		if (executor_overrides.defer_failsafes) {
 			current_overrides.defer_failsafes = true;
 			current_overrides.defer_failsafes_timeout_s = executor_overrides.defer_failsafes_timeout_s;