Allow arming with unhealthy visodom in non-gps modes

Author: Vabe7

ArduCopter/AP_Arming_Copter.cpp

@@ -399,6 +399,31 @@ bool AP_Arming_Copter::gps_checks(bool display_failure)
     return true;
 }
 
+#if HAL_VISUALODOM_ENABLED
+// performs pre_arm visodom related checks and returns true if passed
+bool AP_Arming_Copter::visodom_checks(bool display_failure)
+{
+    // check if fence requires GPS/position
+    bool fence_requires_pos = false;
+#if AP_FENCE_ENABLED
+    // if circular or polygon fence is enabled we need GPS/position
+    fence_requires_pos = (copter.fence.get_enabled_fences() & (AC_FENCE_TYPE_CIRCLE | AC_FENCE_TYPE_POLYGON)) > 0;
+#endif
+
+    // check if flight mode requires GPS/position
+    bool mode_requires_pos = copter.flightmode->requires_GPS() || fence_requires_pos || (copter.simple_mode == Copter::SimpleMode::SUPERSIMPLE);
+
+    // return true if position is not required
+    if (!mode_requires_pos) {
+        return true;
+    } else {
+        // call parent visodom checks
+        return AP_Arming::visodom_checks(display_failure);
+    }
+
+}
+#endif
+
 // check ekf attitude is acceptable
 bool AP_Arming_Copter::pre_arm_ekf_attitude_check()
 {

ArduCopter/AP_Arming_Copter.h

@@ -40,6 +40,9 @@ class AP_Arming_Copter : public AP_Arming
     bool gps_checks(bool display_failure) override;
     bool barometer_checks(bool display_failure) override;
     bool board_voltage_checks(bool display_failure) override;
+#if HAL_VISUALODOM_ENABLED
+    bool visodom_checks(bool display_failure) override;
+#endif
 
     // NOTE! the following check functions *DO NOT* call into AP_Arming!
     bool parameter_checks(bool display_failure);

libraries/AP_Arming/AP_Arming.cpp

@@ -1930,7 +1930,7 @@ bool AP_Arming::rc_checks_copter_sub(const bool display_failure, const RC_Channe
 
 #if HAL_VISUALODOM_ENABLED
 // check visual odometry is working
-bool AP_Arming::visodom_checks(bool display_failure) const
+bool AP_Arming::visodom_checks(bool display_failure)
 {
     if (!check_enabled(ARMING_CHECK_VISION)) {
         return true;

libraries/AP_Arming/AP_Arming.h

@@ -9,6 +9,7 @@
 #include "AP_Arming_config.h"
 #include "AP_InertialSensor/AP_InertialSensor_config.h"
 #include "AP_Proximity/AP_Proximity_config.h"
+#include "AP_VisualOdom/AP_VisualOdom_config.h"
 
 class AP_Arming {
 public:
@@ -257,7 +258,9 @@ class AP_Arming {
     bool servo_checks(bool report) const;
     bool rc_checks_copter_sub(bool display_failure, const class RC_Channel *channels[4]) const;
 
-    bool visodom_checks(bool report) const;
+#if HAL_VISUALODOM_ENABLED
+    virtual bool visodom_checks(bool report);
+#endif
     bool disarm_switch_checks(bool report) const;
 
     // mandatory checks that cannot be bypassed.  This function will only be called if ARMING_CHECK is zero or arming forced