diff --git a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_100hector_mpi_test.world b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_100hector_mpi_test.world
index 203a8ec..8fbf8dd 100644
--- a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_100hector_mpi_test.world
+++ b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_100hector_mpi_test.world
@@ -141,6 +141,13 @@
       </ode> -->
     </physics>
 
+<exercise_opt>
+      <event_signal parallel_type=0 threads=8 />
+	  <collide_space>0</collide_space>
+      <dxhashspace_collide threads=0 />
+      <updatephysics_dxprocessislands parallel_type=0 threads=4 />
+    </exercise_opt>
+
     <!-- <model name="bebop_0">
       <pose>0 0 0.186 0 0 0</pose>
       <include>
diff --git a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_10hector_mpi_test.world b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_10hector_mpi_test.world
index 920af50..968f08b 100644
--- a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_10hector_mpi_test.world
+++ b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_10hector_mpi_test.world
@@ -51,6 +51,13 @@
       </ode> -->
     </physics>
 
+<exercise_opt>
+      <event_signal parallel_type=0 threads=8 />
+	  <collide_space>0</collide_space>
+      <dxhashspace_collide threads=0 />
+      <updatephysics_dxprocessislands parallel_type=0 threads=4 />
+    </exercise_opt>
+
     <!-- <model name="bebop_0">
       <pose>0 0 0.186 0 0 0</pose>
       <include>
diff --git a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_2hector_mpi_test.world b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_2hector_mpi_test.world
index 2bb7518..0184b47 100644
--- a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_2hector_mpi_test.world
+++ b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_2hector_mpi_test.world
@@ -43,6 +43,13 @@
       </ode> -->
     </physics>
 
+<exercise_opt>
+      <event_signal parallel_type=0 threads=8 />
+	  <collide_space>0</collide_space>
+      <dxhashspace_collide threads=0 />
+      <updatephysics_dxprocessislands parallel_type=0 threads=4 />
+    </exercise_opt>
+
     <!-- <model name="bebop_0">
       <pose>0 5 0.186 0 0 0</pose>
       <include>
diff --git a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_30hector_mpi_test.world b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_30hector_mpi_test.world
index 62b7df2..c6c5323 100644
--- a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_30hector_mpi_test.world
+++ b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_30hector_mpi_test.world
@@ -71,6 +71,13 @@
       </ode> -->
     </physics>
 
+<exercise_opt>
+      <event_signal parallel_type=0 threads=8 />
+	  <collide_space>0</collide_space>
+      <dxhashspace_collide threads=0 />
+      <updatephysics_dxprocessislands parallel_type=0 threads=4 />
+    </exercise_opt>
+
     <!-- <model name="bebop_0">
       <pose>0 0 0.186 0 0 0</pose>
       <include>
diff --git a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_4hector_mpi_test.world b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_4hector_mpi_test.world
index 2cff547..42d0019 100644
--- a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_4hector_mpi_test.world
+++ b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_4hector_mpi_test.world
@@ -45,6 +45,13 @@
       </ode> -->
     </physics>
 
+<exercise_opt>
+      <event_signal parallel_type=0 threads=8 />
+	  <collide_space>0</collide_space>
+      <dxhashspace_collide threads=0 />
+      <updatephysics_dxprocessislands parallel_type=0 threads=4 />
+    </exercise_opt>
+
     <!-- <model name="bebop_0">
       <pose>0 5 0.186 0 0 0</pose>
       <include>
diff --git a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_60hector_mpi_test.world b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_60hector_mpi_test.world
index b307780..158b47b 100644
--- a/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_60hector_mpi_test.world
+++ b/Gazebo_Hector_Test/src/hector_quadrotor/hector_quadrotor_gazebo/worlds/kunming_airport_distribution_60hector_mpi_test.world
@@ -101,6 +101,13 @@
       </ode> -->
     </physics>
 
+<exercise_opt>
+      <event_signal parallel_type=0 threads=8 />
+	  <collide_space>0</collide_space>
+      <dxhashspace_collide threads=0 />
+      <updatephysics_dxprocessislands parallel_type=0 threads=4 />
+    </exercise_opt>
+
     <!-- <model name="bebop_0">
       <pose>0 0 0.186 0 0 0</pose>
       <include>