diff --git a/source/armarx/navigation/core/Trajectory.cpp b/source/armarx/navigation/core/Trajectory.cpp
index cfacb438deb2af1104db457f157b742f0ea6f831..de68a8269865b6503e4469b21cf880d68eb17bf8 100644
--- a/source/armarx/navigation/core/Trajectory.cpp
+++ b/source/armarx/navigation/core/Trajectory.cpp
@@ -26,6 +26,7 @@
 #include <VirtualRobot/math/Helpers.h>
 #include <VirtualRobot/math/LinearInterpolatedPose.h>
 
+#include "ArmarXCore/core/exceptions/LocalException.h"
 #include "ArmarXCore/core/exceptions/local/ExpressionException.h"
 #include <ArmarXCore/core/logging/Logging.h>
 
@@ -566,4 +567,13 @@ namespace armarx::navigation::core
     {
         return pts;
     }
+
+
+    float
+    Trajectory::duration(const core::VelocityInterpolation interpolation) const
+    {
+        throw LocalException("not implemented yet");
+        return 0; // FIXME
+    }
+
 } // namespace armarx::navigation::core
diff --git a/source/armarx/navigation/core/Trajectory.h b/source/armarx/navigation/core/Trajectory.h
index b1c727f35a5be6206c757caef8363bc19109173f..4183d1cc59ce8e1dd4ded356e3f3b3efb6c1cb3e 100644
--- a/source/armarx/navigation/core/Trajectory.h
+++ b/source/armarx/navigation/core/Trajectory.h
@@ -32,7 +32,7 @@ namespace armarx::navigation::core
     struct TrajectoryPoint
     {
         Waypoint waypoint;
-        float velocity;
+        float velocity; // [mm/s]
     };
 
     using TrajectoryPoints = std::vector<TrajectoryPoint>;
@@ -97,6 +97,8 @@ namespace armarx::navigation::core
 
         const std::vector<TrajectoryPoint>& points() const;
 
+        float duration(core::VelocityInterpolation interpolation) const;
+
     private:
         std::vector<TrajectoryPoint> pts;
     };