diff --git a/conf/airframes/examples/quadrotor_lisa_mx.xml b/conf/airframes/examples/quadrotor_lisa_mx.xml
index 30341971ab..f9bb619787 100644
--- a/conf/airframes/examples/quadrotor_lisa_mx.xml
+++ b/conf/airframes/examples/quadrotor_lisa_mx.xml
@@ -17,6 +17,7 @@
 
     <target name="nps" board="pc">
       <module name="fdm" type="jsbsim"/>
+      <module name="gps" type="nps"/>
     </target>
 
     <module name="radio_control" type="spektrum">
diff --git a/conf/modules/gps_furuno.xml b/conf/modules/gps_furuno.xml
index b7d9f792ab..dc5c3d84d8 100644
--- a/conf/modules/gps_furuno.xml
+++ b/conf/modules/gps_furuno.xml
@@ -49,16 +49,4 @@
       endif
     </raw>
   </makefile>
-  <makefile target="nps">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
-  </makefile>
-  <makefile target="sim">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
-  </makefile>
 </module>
diff --git a/conf/modules/gps_mediatek_diy.xml b/conf/modules/gps_mediatek_diy.xml
index 3c9a8c8973..b79ef51fec 100644
--- a/conf/modules/gps_mediatek_diy.xml
+++ b/conf/modules/gps_mediatek_diy.xml
@@ -45,16 +45,4 @@
       endif
     </raw>
   </makefile>
-  <makefile target="nps">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
-  </makefile>
-  <makefile target="sim">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
-  </makefile>
 </module>
diff --git a/conf/modules/gps_nmea.xml b/conf/modules/gps_nmea.xml
index 5e4d8a18ce..367c53d977 100644
--- a/conf/modules/gps_nmea.xml
+++ b/conf/modules/gps_nmea.xml
@@ -45,16 +45,4 @@
       endif
     </raw>
   </makefile>
-  <makefile target="nps">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
-  </makefile>
-  <makefile target="sim">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
-  </makefile>
 </module>
diff --git a/conf/modules/gps_nps.xml b/conf/modules/gps_nps.xml
new file mode 100644
index 0000000000..5ebd63cd07
--- /dev/null
+++ b/conf/modules/gps_nps.xml
@@ -0,0 +1,22 @@
+<!DOCTYPE module SYSTEM "module.dtd">
+
+<module name="gps_nps">
+  <doc>
+    <description>
+      Simulated GPS for NPS.
+      For NPS simulator. Can model GPS noise, bias and latency.
+      The GPS sensor configuration is done in the header file referenced by NPS_SENSORS_PARAMS.
+    </description>
+  </doc>
+  <header>
+    <file name="gps.h" dir="subsystems"/>
+  </header>
+  <init fun="gps_nps_init()"/>
+  <!--periodic fun="gps_periodic_check()" freq="1." autorun="TRUE"/-->
+  <makefile target="nps">
+    <file name="gps.c" dir="subsystems"/>
+    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
+    <define name="USE_GPS"/>
+    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
+  </makefile>
+</module>
diff --git a/conf/modules/gps_piksi.xml b/conf/modules/gps_piksi.xml
index e5e269ea70..3970c27794 100644
--- a/conf/modules/gps_piksi.xml
+++ b/conf/modules/gps_piksi.xml
@@ -49,16 +49,4 @@
       endif
     </raw>
   </makefile>
-  <makefile target="nps">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
-  </makefile>
-  <makefile target="sim">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
-  </makefile>
 </module>
diff --git a/conf/modules/gps_sim.xml b/conf/modules/gps_sim.xml
new file mode 100644
index 0000000000..ff98572b9b
--- /dev/null
+++ b/conf/modules/gps_sim.xml
@@ -0,0 +1,21 @@
+<!DOCTYPE module SYSTEM "module.dtd">
+
+<module name="gps_sim">
+  <doc>
+    <description>
+      Simulated GPS
+      For simple fixedwing OCaml simulator. Does not model any GPS inaccuracies/noise.
+    </description>
+  </doc>
+  <header>
+    <file name="gps.h" dir="subsystems"/>
+  </header>
+  <init fun="gps_sim_init()"/>
+  <!--periodic fun="gps_periodic_check()" freq="1." autorun="TRUE"/-->
+  <makefile target="sim">
+    <file name="gps.c" dir="subsystems"/>
+    <file name="gps_sim.c" dir="subsystems/gps"/>
+    <define name="USE_GPS"/>
+    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
+  </makefile>
+</module>
diff --git a/conf/modules/gps_sim_hitl.xml b/conf/modules/gps_sim_hitl.xml
new file mode 100644
index 0000000000..e92f600904
--- /dev/null
+++ b/conf/modules/gps_sim_hitl.xml
@@ -0,0 +1,28 @@
+<!DOCTYPE module SYSTEM "module.dtd">
+
+<module name="gps_sim_hitl">
+  <doc>
+    <description>
+      Sim HITL GPS
+      Simulate GPS for HITL (HardwareInTheLoop) from rotorcrafts horizontal/vertical reference system.
+    </description>
+    <configure name="GPS_LED" value="2" description="LED number to indicate fix or none"/>
+  </doc>
+  <header>
+    <file name="gps.h" dir="subsystems"/>
+  </header>
+  <init fun="gps_sim_hitl_init()"/>
+  <!--periodic fun="gps_periodic_check()" freq="1." autorun="TRUE"/-->
+  <event fun="gps_sim_hitl_event()"/>
+  <makefile target="ap" firmware="rotorcraft">
+    <configure name="GPS_LED" default="none"/>
+
+    <file name="gps.c" dir="subsystems"/>
+    <file name="gps_sim_hitl.c" dir="subsystems/gps"/>
+
+    <define name="HITL"/>
+    <define name="USE_GPS"/>
+    <define name="GPS_LED" value="$(GPS_LED)" cond="ifneq ($(GPS_LED),none)"/>
+    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_hitl.h" type="string"/>
+  </makefile>
+</module>
diff --git a/conf/modules/gps_sirf.xml b/conf/modules/gps_sirf.xml
index b892f1652d..dca29eadfc 100644
--- a/conf/modules/gps_sirf.xml
+++ b/conf/modules/gps_sirf.xml
@@ -45,16 +45,4 @@
       endif
     </raw>
   </makefile>
-  <makefile target="nps">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
-  </makefile>
-  <makefile target="sim">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
-  </makefile>
 </module>
diff --git a/conf/modules/gps_skytraq.xml b/conf/modules/gps_skytraq.xml
index 969710ebf8..cb26f6bec8 100644
--- a/conf/modules/gps_skytraq.xml
+++ b/conf/modules/gps_skytraq.xml
@@ -45,16 +45,4 @@
       endif
     </raw>
   </makefile>
-  <makefile target="nps">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
-  </makefile>
-  <makefile target="sim">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
-  </makefile>
 </module>
diff --git a/conf/modules/gps_ublox.xml b/conf/modules/gps_ublox.xml
index 71ff25105b..988437c20b 100644
--- a/conf/modules/gps_ublox.xml
+++ b/conf/modules/gps_ublox.xml
@@ -46,17 +46,5 @@
       endif
     </raw>
   </makefile>
-  <makefile target="nps">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
-  </makefile>
-  <makefile target="sim">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
-  </makefile>
 </module>
 
diff --git a/conf/modules/gps_ubx_i2c.xml b/conf/modules/gps_ubx_i2c.xml
index ab1e733f3c..760231411c 100644
--- a/conf/modules/gps_ubx_i2c.xml
+++ b/conf/modules/gps_ubx_i2c.xml
@@ -4,6 +4,7 @@
   <doc>
     <description>
       U-blox GPS (I2C)
+      Extends the gps_ublox to provide I2C connectivity.
     </description>
     <configure name="GPS_UBX_I2C_DEV" value="i2cX" description="set i2c peripheral (default: i2c1)"/>
   </doc>
@@ -17,7 +18,7 @@
   <periodic fun="gps_ubx_i2c_periodic()" freq="10."/>
   <event fun="GpsUbxi2cEvent()"/>
 
-  <makefile>
+  <makefile target="ap">
     <configure name="GPS_UBX_I2C_DEV" default="i2c1" case="upper|lower"/>
     <define name="USE_$(GPS_UBX_I2C_DEV_UPPER)"/>
     <define name="GPS_UBX_I2C_DEV" value="$(GPS_UBX_I2C_DEV_LOWER)"/>
diff --git a/conf/modules/gps_udp.xml b/conf/modules/gps_udp.xml
index 241f64ce8b..3bde0c132d 100644
--- a/conf/modules/gps_udp.xml
+++ b/conf/modules/gps_udp.xml
@@ -38,16 +38,4 @@
       endif
     </raw>
   </makefile>
-  <makefile target="nps">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim_nps.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim_nps.h" type="string"/>
-  </makefile>
-  <makefile target="sim">
-    <file name="gps.c" dir="subsystems"/>
-    <file name="gps_sim.c" dir="subsystems/gps"/>
-    <define name="USE_GPS"/>
-    <define name="GPS_TYPE_H" value="subsystems/gps/gps_sim.h" type="string"/>
-  </makefile>
 </module>
diff --git a/sw/airborne/subsystems/gps/gps_sim_nps.h b/sw/airborne/subsystems/gps/gps_sim_nps.h
index d4fc18bbe8..c1de3eee0d 100644
--- a/sw/airborne/subsystems/gps/gps_sim_nps.h
+++ b/sw/airborne/subsystems/gps/gps_sim_nps.h
@@ -11,6 +11,6 @@ extern bool gps_has_fix;
 
 extern void gps_feed_value();
 
-extern void gps_nps_impl_init();
+extern void gps_nps_init();
 
 #endif /* GPS_SIM_NPS_H */