Added trajectory tilt angle computed field

src/flightlog.js

@@ -30,7 +30,7 @@ import {
  * Window based smoothing of fields is offered.
  */
 export function FlightLog(logData) {
-  let ADDITIONAL_COMPUTED_FIELD_COUNT = 20 /** attitude + PID_SUM + PID_ERROR + RCCOMMAND_SCALED + GPS coord, distance and azimuth **/,
+  let ADDITIONAL_COMPUTED_FIELD_COUNT = 21 /** attitude + PID_SUM + PID_ERROR + RCCOMMAND_SCALED + GPS coord, distance, azimuth, trajectory tilt angle **/,
     that = this,
     logIndex = 0,
     logIndexes = new FlightLogIndex(logData),
@@ -285,7 +285,8 @@ export function FlightLog(logData) {
       fieldNames.push("axisError[0]", "axisError[1]", "axisError[2]"); // Custom calculated error field
     }
     if (!that.isFieldDisabled().GPS) {
-      fieldNames.push("gpsCartesianCoords[0]", "gpsCartesianCoords[1]", "gpsCartesianCoords[2]", "gpsDistance", "gpsHomeAzimuth"); // GPS coords in cartesian system
+      // GPS coords in cartesian system, trajectory tilt angle
+      fieldNames.push("gpsCartesianCoords[0]", "gpsCartesianCoords[1]", "gpsCartesianCoords[2]", "gpsDistance", "gpsHomeAzimuth", "gpsTrajectoryTiltAngle");
     }
 
     fieldNameToIndex = {};
@@ -636,6 +637,11 @@ export function FlightLog(logData) {
       fieldNameToIndex["GPS_coord[1]"],
       fieldNameToIndex["GPS_altitude"],
     ];
+    let gpsVelNED = [
+      fieldNameToIndex["GPS_velned[0]"],
+      fieldNameToIndex["GPS_velned[1]"],
+      fieldNameToIndex["GPS_velned[2]"],
+    ];
 
     const flightModeFlagsIndex = fieldNameToIndex["flightModeFlags"]; // This points to the flightmode data
 
@@ -705,6 +711,9 @@ export function FlightLog(logData) {
       gpsCoord = false;
     }
 
+    if (!gpsVelNED[0]) {
+      gpsVelNED = false;
+    }
 
     sourceChunkIndex = 0;
     destChunkIndex = 0;
@@ -746,7 +755,7 @@ export function FlightLog(logData) {
             if (m < 1.0) {
                 // reconstruct .w of unit quaternion
                 q.w = Math.sqrt(1.0 - m);
-            } else {                
+            } else {
                 // normalize [0,x,y,z]
                 m = Math.sqrt(m);
                 q.x /= m;
@@ -877,7 +886,7 @@ export function FlightLog(logData) {
             }
           }
 
-          // Calculate cartesian coords by GPS
+          // Calculate cartesian coords, azimuth and trajectory tilt angle by GPS
           if (!that.isFieldDisabled().GPS) {
             if (gpsTransform && gpsCoord && srcFrame[gpsCoord[0]]) {
               const gpsCartesianCoords = gpsTransform.WGS_BS(srcFrame[gpsCoord[0]] / 10000000, srcFrame[gpsCoord[1]] / 10000000, srcFrame[gpsCoord[2]] / 10);
@@ -898,6 +907,23 @@ export function FlightLog(logData) {
               destFrame[fieldIndex++] = 0;
               destFrame[fieldIndex++] = 0;
             }
+
+            // Calculate trajectory tilt angle by NED GPS velocity
+            if (gpsVelNED) {
+              const Vn = srcFrame[gpsVelNED[0]],
+                    Ve = srcFrame[gpsVelNED[1]],
+                    Vd = srcFrame[gpsVelNED[2]];
+              const velocity = Math.hypot(Vn, Ve, Vd);
+              const minVelo = 5;  // 5cm/s limit to prevent division by zero and miss tiny noise values
+              let trajectoryTiltAngle = 0;
+              if (velocity > minVelo) {
+                const angleSin = Math.max(-1, Math.min(1, Vd / velocity));
+                trajectoryTiltAngle = -Math.asin(angleSin) * 180 / Math.PI; // [degree], if velo is up then >0
+              }
+              destFrame[fieldIndex++] = trajectoryTiltAngle;
+            } else {
+              destFrame[fieldIndex++] = 0;
+            }
           }
 
           // Remove empty fields at the end

src/flightlog_fields_presenter.js

@@ -141,6 +141,7 @@ const FRIENDLY_FIELD_NAMES = {
   "gpsCartesianCoords[2]": "GPS Coords [Z]",
   gpsDistance:     "GPS Home distance",
   gpsHomeAzimuth:     "GPS Home azimuth",
+  gpsTrajectoryTiltAngle: "GPS Traject. tilt angle",
 };
 
 const DEBUG_FRIENDLY_FIELD_NAMES_INITIAL = {
@@ -1853,6 +1854,7 @@ FlightLogFieldPresenter.decodeFieldToFriendly = function (
     case "gpsDistance":
       return `${value.toFixed(0)} m`;
     case "gpsHomeAzimuth":
+    case "gpsTrajectoryTiltAngle":
       return `${value.toFixed(1)} °`;
     case "magADC[0]":
     case "magADC[1]":