diff --git a/source/armarx/navigation/human/types.cpp b/source/armarx/navigation/human/types.cpp
index 5b6d3d88a790e05090f038b86a5c83e391a09b19..6296ba6e4c974706ab957fd9229291694ec7d5a9 100644
--- a/source/armarx/navigation/human/types.cpp
+++ b/source/armarx/navigation/human/types.cpp
@@ -3,7 +3,7 @@
 namespace armarx::navigation::human
 {
     core::Pose2D
-    Human::estimateAt(DateTime& time) const
+    Human::estimateAt(const DateTime& time) const
     {
         double dt = (time - detectionTime).toSecondsDouble();
         core::Pose2D estimation{pose};
diff --git a/source/armarx/navigation/human/types.h b/source/armarx/navigation/human/types.h
index 6b66e7c6eda19641d632a278ae886458fee24e15..625fa764837ed5194ce884970e027bf92504ac00 100644
--- a/source/armarx/navigation/human/types.h
+++ b/source/armarx/navigation/human/types.h
@@ -34,7 +34,7 @@ namespace armarx::navigation::human
         Eigen::Vector2f linearVelocity;
         DateTime detectionTime;
 
-        core::Pose2D estimateAt(DateTime& time) const;
+        core::Pose2D estimateAt(const DateTime& time) const;
     };
 
     struct HumanGroup