diff --git a/variants/units/apollo/unit_data.hpp b/variants/units/apollo/unit_data.hpp
index ae1934e..0081a20 100644
--- a/variants/units/apollo/unit_data.hpp
+++ b/variants/units/apollo/unit_data.hpp
@@ -45,6 +45,7 @@ struct UnitData {
              platform.get<Accelerometer>(),
              std::experimental::nullopt,
              std::experimental::make_optional(&platform.get<Magnetometer>()),
+             std::experimental::nullopt,
              world, inputSource, motorMapper, communicator
       ) {
   }
diff --git a/variants/units/zephyrus/unit_data.hpp b/variants/units/zephyrus/unit_data.hpp
index 078fc3c..ff59739 100644
--- a/variants/units/zephyrus/unit_data.hpp
+++ b/variants/units/zephyrus/unit_data.hpp
@@ -53,6 +53,7 @@ struct UnitData {
       world(location, attitude, communicator),
       inputSource(communicator),
       system(platform.get<Gyroscope>(), platform.get<Accelerometer>(),
+             std::experimental::nullopt,
              std::experimental::nullopt,
              std::experimental::nullopt,
              world, inputSource, motorMapper, communicator) {
diff --git a/variants/units/zeus/unit_data.hpp b/variants/units/zeus/unit_data.hpp
index d3920e5..5b3b71d 100644
--- a/variants/units/zeus/unit_data.hpp
+++ b/variants/units/zeus/unit_data.hpp
@@ -41,6 +41,7 @@ struct UnitData {
       world(location, attitude, communicator),
       inputSource(communicator),
       system(platform.get<Gyroscope>(), platform.get<Accelerometer>(),
+             std::experimental::nullopt,
              std::experimental::nullopt,
              std::experimental::nullopt,
              world, inputSource, motorMapper, communicator) {