ArduCopter: add Copter flight option for requiring position to arm

ArduCopter/AP_Arming.cpp

@@ -444,7 +444,7 @@ bool AP_Arming_Copter::mandatory_gps_checks(bool display_failure)
     fence_requires_gps = (copter.fence.get_enabled_fences() & (AC_FENCE_TYPE_CIRCLE | AC_FENCE_TYPE_POLYGON)) > 0;
     #endif
 
-    if (mode_requires_gps) {
+    if (mode_requires_gps || copter.option_is_enabled(Copter::FlightOption::REQUIRE_POSITION_FOR_ARMING)) {
         if (!copter.position_ok()) {
             // vehicle level position estimate checks
             check_failed(display_failure, "Need Position Estimate");

ArduCopter/Copter.h

@@ -626,6 +626,7 @@ class Copter : public AP_Vehicle {
         DISABLE_THRUST_LOSS_CHECK     = (1<<0),   // 1
         DISABLE_YAW_IMBALANCE_WARNING = (1<<1),   // 2
         RELEASE_GRIPPER_ON_THRUST_LOSS = (1<<2),  // 4
+        REQUIRE_POSITION_FOR_ARMING =   (1<<3),   // 8
     };
     // returns true if option is enabled for this vehicle
     bool option_is_enabled(FlightOption option) const {

ArduCopter/Parameters.cpp

@@ -1000,7 +1000,7 @@ const AP_Param::GroupInfo ParametersG2::var_info[] = {
     // @Param: FLIGHT_OPTIONS
     // @DisplayName: Flight mode options
     // @Description: Flight mode specific options
-    // @Bitmask: 0:Disable thrust loss check, 1:Disable yaw imbalance warning, 2:Release gripper on thrust loss
+    // @Bitmask: 0:Disable thrust loss check, 1:Disable yaw imbalance warning, 2:Release gripper on thrust loss, 3:Require position for arming
     // @User: Advanced
     AP_GROUPINFO("FLIGHT_OPTIONS", 44, ParametersG2, flight_options, 0),
 

Tools/autotest/arducopter.py

@@ -11535,6 +11535,39 @@ def GripperReleaseOnThrustLoss(self):
         self.do_RTL()
         self.reboot_sitl()
 
+    def assert_home_position_not_set(self):
+        try:
+            self.poll_home_position()
+        except NotAchievedException:
+            return
+
+        # if home.lng != 0: etc
+
+        raise NotAchievedException("Home is set when it shouldn't be")
+
+    def REQUIRE_POSITION_FOR_ARMING(self):
+        '''check FlightOption::REQUIRE_POSITION_FOR_ARMING works'''
+        self.context_push()
+        self.set_parameters({
+            "SIM_GPS_NUMSATS": 3,  # EKF does not like < 6
+        })
+        self.reboot_sitl()
+        self.change_mode('STABILIZE')
+        self.wait_prearm_sys_status_healthy()
+        self.assert_home_position_not_set()
+        self.arm_vehicle()
+        self.disarm_vehicle()
+        self.change_mode('LOITER')
+        self.assert_prearm_failure("waiting for home", other_prearm_failures_fatal=False)
+
+        self.change_mode('STABILIZE')
+        self.set_parameters({
+            "FLIGHT_OPTIONS": 8,
+        })
+        self.assert_prearm_failure("Need Position Estimate", other_prearm_failures_fatal=False)
+        self.context_pop()
+        self.reboot_sitl()
+
     def tests2b(self):  # this block currently around 9.5mins here
         '''return list of all tests'''
         ret = ([
@@ -11626,6 +11659,7 @@ def tests2b(self):  # this block currently around 9.5mins here
             self.GuidedWeatherVane,
             self.Clamp,
             self.GripperReleaseOnThrustLoss,
+            self.REQUIRE_POSITION_FOR_ARMING,
         ])
         return ret