Plane: remove all threat logic in adsb lib in favor of avoidance lib

ArduPlane/Plane.h

@@ -630,17 +630,6 @@ private:
 #endif
 
     AP_ADSB adsb {ahrs};
-    struct {
-
-        // flag to signify the current mode is set by ADSB evasion logic
-        bool is_evading:1;
-
-        // generic timestamp for evasion algorithms
-        uint32_t timestamp_ms;
-
-        // previous wp to restore to when switching between modes back to AUTO
-        Location prev_wp;
-    } adsb_state;
 
     // Outback Challenge Failsafe Support
 #if OBC_FAILSAFE == ENABLED
@@ -1017,9 +1006,6 @@ private:
     void update_logging2(void);
     void terrain_update(void);
     void adsb_update(void);
-    bool adsb_evasion_start(void);
-    void adsb_evasion_stop(void);
-    void adsb_evasion_ongoing(void);
     void update_flight_mode(void);
     void stabilize();
     void set_servos_idle(void);

ArduPlane/adsb.cpp

@@ -27,100 +27,10 @@
  */
 
 /*
-  handle periodic adsb database maintenance and handle threats
+  handle periodic adsb database maintenance
  */
 void Plane::adsb_update(void)
 {
     adsb.update();
-
-    if (!adsb.get_is_evading_threat()) {
-        if (adsb.get_possible_threat()) {
-            bool evasion_start_success = adsb_evasion_start();
-            adsb.set_is_evading_threat(evasion_start_success);
-        }
-    } else if (adsb_state.is_evading) {
-        // there has been no manual override, handle an auto-evasion
-        if (!adsb.get_possible_threat()) {
-                adsb.set_is_evading_threat(false);
-                adsb_evasion_stop();
-                adsb_state.is_evading = false;
-        } else {
-            adsb_evasion_ongoing();
-        }
-    }
-}
-
-/*
- * This fires once at the moment we realize there is a threat
- */
-bool Plane::adsb_evasion_start(void)
-{
-    if (control_mode != AUTO) {
-        // evasion is only supported while in AUTO mode
-        return false;
-    }
-    if (mission.get_current_nav_cmd().id == MAV_CMD_NAV_TAKEOFF ||
-        mission.get_current_nav_cmd().id == MAV_CMD_NAV_LAND) {
-        // evasion during a plane take-off or land can result in a crash. Ignore ADS-B traffic
-        return false;
-    }
-
-    adsb_state.timestamp_ms =  millis();
-    adsb_state.prev_wp = prev_WP_loc; // must be done BEFORE set_mode()
-
-    switch(adsb.get_behavior()) {
-    case AP_ADSB::ADSB_BEHAVIOR_NONE:
-    default:
-        gcs_send_text(MAV_SEVERITY_CRITICAL, "ADS-B threat found, no action taken");
-        break;
-
-    case AP_ADSB::ADSB_BEHAVIOR_GUIDED:
-        gcs_send_text(MAV_SEVERITY_CRITICAL, "ADS-B threat found, switching to GUIDED mode");
-        set_mode(GUIDED);
-        adsb_state.is_evading = true; // must be done AFTER set_mode()
-        break;
-
-    case AP_ADSB::ADSB_BEHAVIOR_LOITER:
-    case AP_ADSB::ADSB_BEHAVIOR_LOITER_AND_DESCEND:
-        gcs_send_text(MAV_SEVERITY_CRITICAL, "ADS-B threat found, performing LOITER");
-        set_mode(LOITER);
-        adsb_state.is_evading = true; // must be done after set_mode()
-        break;
-    } // switch behavior
-
-    return true;
 }
 
-/*
- * This fires once at the moment we realize there is no longer a threat
- */
-void Plane::adsb_evasion_stop(void)
-{
-    gcs_send_text(MAV_SEVERITY_CRITICAL, "ADS-B threat gone, continuing mission");
-
-    FlightMode prev_control_mode = control_mode;
-    set_mode(AUTO);
-    if (prev_control_mode == LOITER)
-    {
-        // if resuming from loiter, smoothly get back on track
-        prev_WP_loc = adsb_state.prev_wp;
-        auto_state.no_crosstrack = false;
-    }
-}
-
-/*
- * This fires once per second while evading a threat
- */
-void Plane::adsb_evasion_ongoing(void)
-{
-    uint32_t now = millis();
-
-    if (control_mode == LOITER &&
-        adsb.get_behavior() == AP_ADSB::ADSB_BEHAVIOR_LOITER_AND_DESCEND &&
-        now - adsb_state.timestamp_ms >= 1000)
-    {
-        // slowly reduce altitude 100 cm/s while loitering. Drive into the ground if threat persists
-         adsb_state.timestamp_ms = now;
-         next_WP_loc.alt -= 100;
-    }
-}

ArduPlane/system.cpp

@@ -344,13 +344,6 @@ void Plane::set_mode(enum FlightMode mode)
     guided_state.last_forced_rpy_ms.zero();
     guided_state.last_forced_throttle_ms = 0;
 
-    // always reset this because we don't know who called set_mode. In evasion
-    // behavior you should set this flag after set_mode so you know the evasion
-    // logic is controlling the mode. This allows manual override of the mode
-    // to exit evasion behavior automatically but if the mode is manually switched
-    // then we won't resume AUTO after an evasion
-    adsb_state.is_evading = false;
-
     // set mode
     previous_mode = control_mode;
     control_mode = mode;