diff --git a/src/processor/processor_imu2d.cpp b/src/processor/processor_imu2d.cpp
index 52633147eeebf61970a0963aa1b43b115ad811c0..5c5e911c1edcf6319946b1d3a095e29317820522 100644
--- a/src/processor/processor_imu2d.cpp
+++ b/src/processor/processor_imu2d.cpp
@@ -179,6 +179,7 @@ namespace wolf {
                                       const double _dt,
                                       VectorComposite& _x_plus_delta) const
   {
+    assert(_x.includesStructure("POV") && "Any key missing in _x");
     assert(_delta.size() == 5 && "Wrong _delta vector size");
     assert(_dt >= 0 && "Time interval _dt is negative!");