SITL: fixed up airspeed parameters

use a separate airspeed structure and separate ratio per sensor

libraries/SITL/SIM_MS5525.cpp

@@ -73,6 +73,6 @@ void MS5525::get_pressure_temperature_readings(float &P_Pa, float &Temp_C)
 
     // To Do: Add a sensor board temperature offset parameter
     Temp_C = (KELVIN_TO_C(SSL_AIR_TEMPERATURE * theta)) + 25.0;
-    const uint8_t sensor_ofs = 0;  // TODO: work out which SITL parameter to use
-    P_Pa = AP::sitl()->state.airspeed_raw_pressure[sensor_ofs] + AP::sitl()->arspd_offset[sensor_ofs];
+    const uint8_t instance = 0;  // TODO: work out which sensor this is
+    P_Pa = AP::sitl()->state.airspeed_raw_pressure[instance] + AP::sitl()->airspeed[instance].offset;
 }

libraries/SITL/SITL.cpp

@@ -66,7 +66,6 @@ const AP_Param::GroupInfo SIM::var_info[] = {
     AP_GROUPINFO("TERRAIN",       34, SIM,  terrain_enable, 1),
     AP_GROUPINFO("FLOW_RATE",     35, SIM,  flow_rate, 10),
     AP_GROUPINFO("FLOW_DELAY",    36, SIM,  flow_delay, 0),
-    AP_GROUPINFO("WIND_DELAY",    40, SIM,  wind_delay, 0),
     AP_GROUPINFO("ADSB_COUNT",    45, SIM,  adsb_plane_count, -1),
     AP_GROUPINFO("ADSB_RADIUS",   46, SIM,  adsb_radius_m, 10000),
     AP_GROUPINFO("ADSB_ALT",      47, SIM,  adsb_altitude_m, 1000),
@@ -282,22 +281,11 @@ const AP_Param::GroupInfo SIM::var_info3[] = {
 
     AP_GROUPINFO("ESC_TELEM", 40, SIM, esc_telem, 1),
 
-    // user settable parameters for the 1st airspeed sensor
-    AP_GROUPINFO("ARSPD_RND",     50, SIM,  arspd_noise[0], 2.0),
-    AP_GROUPINFO("ARSPD_OFS",     51, SIM,  arspd_offset[0], 2013),
-    AP_GROUPINFO("ARSPD_FAIL",    52, SIM,  arspd_fail[0], 0),
-    AP_GROUPINFO("ARSPD_FAILP",   53, SIM,  arspd_fail_pressure[0], 0),
-    AP_GROUPINFO("ARSPD_PITOT",   54, SIM,  arspd_fail_pitot_pressure[0], 0),
-
-    // user settable parameters for the 2nd airspeed sensor
-    AP_GROUPINFO("ARSPD2_RND",    56, SIM,  arspd_noise[1], 2.0),
-    AP_GROUPINFO("ARSPD2_OFS",    57, SIM,  arspd_offset[1], 2013),
-    AP_GROUPINFO("ARSPD2_FAIL",   58, SIM,  arspd_fail[1], 0),
-    AP_GROUPINFO("ARSPD2_FAILP",  59, SIM,  arspd_fail_pressure[1], 0),
-    AP_GROUPINFO("ARSPD2_PITOT",  60, SIM,  arspd_fail_pitot_pressure[1], 0),
+    AP_SUBGROUPINFO(airspeed[0], "ARSPD_", 50, SIM, SIM::AirspeedParm),
+#if AIRSPEED_MAX_SENSORS > 1
+    AP_SUBGROUPINFO(airspeed[1], "ARSPD2_", 51, SIM, SIM::AirspeedParm),
+#endif
 
-    // user settable common airspeed parameters
-    AP_GROUPINFO("ARSPD_SIGN",    62, SIM,  arspd_signflip, 0),
 
 #ifdef SFML_JOYSTICK
     AP_SUBGROUPEXTENSION("",      63, SIM,  var_sfml_joystick),
@@ -323,6 +311,19 @@ const AP_Param::GroupInfo SIM::BaroParm::var_info[] = {
     AP_GROUPEND
 };
 
+// user settable parameters for airspeed sensors
+const AP_Param::GroupInfo SIM::AirspeedParm::var_info[] = {
+        // user settable parameters for the 1st airspeed sensor
+    AP_GROUPINFO("RND",     1, SIM::AirspeedParm,  noise, 2.0),
+    AP_GROUPINFO("OFS",     2, SIM::AirspeedParm,  offset, 2013),
+    AP_GROUPINFO("FAIL",    3, SIM::AirspeedParm,  fail, 0),
+    AP_GROUPINFO("FAILP",   4, SIM::AirspeedParm,  fail_pressure, 0),
+    AP_GROUPINFO("PITOT",   5, SIM::AirspeedParm,  fail_pitot_pressure, 0),
+    AP_GROUPINFO("SIGN",    6, SIM::AirspeedParm,  signflip, 0),
+    AP_GROUPINFO("RATIO",   7, SIM::AirspeedParm,  ratio, 1.99),
+    AP_GROUPEND
+};
+
 #if HAL_SIM_GPS_ENABLED
 // GPS SITL parameters
 const AP_Param::GroupInfo SIM::var_gps[] = {

libraries/SITL/SITL.h

@@ -7,6 +7,7 @@
 #include <AP_Math/AP_Math.h>
 #include <GCS_MAVLink/GCS_MAVLink.h>
 #include <AP_Baro/AP_Baro.h>
+#include <AP_Airspeed/AP_Airspeed.h>
 #include <AP_Common/Location.h>
 #include <AP_Compass/AP_Compass.h>
 #include <AP_InertialSensor/AP_InertialSensor.h>
@@ -78,7 +79,7 @@ struct sitl_fdm {
     } scanner;
 
     float rangefinder_m[RANGEFINDER_MAX_INSTANCES];
-    float airspeed_raw_pressure[2];
+    float airspeed_raw_pressure[AIRSPEED_MAX_SENSORS];
 
     struct {
         float speed;
@@ -113,6 +114,9 @@ public:
         for (uint8_t i=0; i<BARO_MAX_INSTANCES; i++) {
             AP_Param::setup_object_defaults(&baro[i], baro[i].var_info);
         }
+        for (uint8_t i=0; i<AIRSPEED_MAX_SENSORS; i++) {
+            AP_Param::setup_object_defaults(&airspeed[i], airspeed[i].var_info);
+        }
         if (_singleton != nullptr) {
             AP_HAL::panic("Too many SITL instances");
         }
@@ -163,12 +167,6 @@ public:
     Matrix3f ahrs_rotation;
     Matrix3f ahrs_rotation_inv;
 
-    AP_Float arspd_noise[2];  // pressure noise
-    AP_Float arspd_fail[2];   // airspeed value in m/s to fail to
-    AP_Float arspd_fail_pressure[2]; // pitot tube failure pressure in Pa
-    AP_Float arspd_fail_pitot_pressure[2]; // pitot tube failure pressure in Pa
-    AP_Float arspd_offset[2]; // airspeed sensor offset in m/s
-
     AP_Float mag_noise;   // in mag units (earth field is 818)
     AP_Vector3f mag_mot;  // in mag units per amp
     AP_Vector3f mag_ofs[HAL_COMPASS_MAX_SENSORS];  // in mag units
@@ -255,6 +253,20 @@ public:
     };
     BaroParm baro[BARO_MAX_INSTANCES];
 
+    // airspeed parameters
+    class AirspeedParm {
+    public:
+        static const struct AP_Param::GroupInfo var_info[];
+        AP_Float noise;  // pressure noise
+        AP_Float fail;   // airspeed value in m/s to fail to
+        AP_Float fail_pressure; // pitot tube failure pressure in Pa
+        AP_Float fail_pitot_pressure; // pitot tube failure pressure in Pa
+        AP_Float offset; // airspeed sensor offset in m/s
+        AP_Float ratio; // airspeed ratios
+        AP_Int8  signflip;
+    };
+    AirspeedParm airspeed[AIRSPEED_MAX_SENSORS];
+    
     // EFI type
     enum EFIType {
         EFI_TYPE_NONE = 0,
@@ -282,7 +294,6 @@ public:
     AP_Float wind_type_coef;
 
     AP_Int16  mag_delay; // magnetometer data delay in ms
-    AP_Int16  wind_delay; // windspeed data delay in ms
 
     // ADSB related run-time options
     AP_Int16 adsb_plane_count;
@@ -308,9 +319,6 @@ public:
     
     AP_Int8 thermal_scenario;
 
-    // differential pressure sensor tube order
-    AP_Int8 arspd_signflip;
-
     // weight on wheels pin
     AP_Int8 wow_pin;