diff --git a/rmf_traffic/CMakeLists.txt b/rmf_traffic/CMakeLists.txt
index d5516187..43e5a092 100644
--- a/rmf_traffic/CMakeLists.txt
+++ b/rmf_traffic/CMakeLists.txt
@@ -76,6 +76,17 @@ if(BUILD_TESTING AND ament_cmake_catch2_FOUND AND rmf_cmake_uncrustify_FOUND)
     CONFIG_FILE ${uncrustify_config_file}
     MAX_LINE_LENGTH 80
   )
+
+  file(GLOB_RECURSE regress_DetectConflict_fail_resources "test/resources/regress_DetectConflict_fail/*")
+  foreach(resource ${regress_DetectConflict_fail_resources})
+    get_filename_component(resource_name ${resource} NAME)
+    configure_file(${resource} "${CMAKE_CURRENT_BINARY_DIR}/resources/${resource_name}" COPYONLY)
+  endforeach()
+
+  target_compile_definitions(test_rmf_traffic
+    PRIVATE
+    "RESOURCES_DIR=\"${CMAKE_CURRENT_BINARY_DIR}/resources/\"")
+
 endif()
 
 if(using_new_fcl)
diff --git a/rmf_traffic/package.xml b/rmf_traffic/package.xml
index 76ebb7bc..3d9ae315 100644
--- a/rmf_traffic/package.xml
+++ b/rmf_traffic/package.xml
@@ -14,7 +14,7 @@
   <build_depend>libccd-dev</build_depend>
   <build_depend>libfcl-dev</build_depend>
   <!-- Uncomment the line below for fcl-0.6 -->
-  <!-- <build_depend>fcl</build_depend> -->
+  <build_depend>fcl</build_depend>
 
   <test_depend>ament_cmake_catch2</test_depend>
   <test_depend>rmf_cmake_uncrustify</test_depend>
diff --git a/rmf_traffic/test/regression/regress_DetectConflict_fail.cpp b/rmf_traffic/test/regression/regress_DetectConflict_fail.cpp
new file mode 100644
index 00000000..b7e5b41d
--- /dev/null
+++ b/rmf_traffic/test/regression/regress_DetectConflict_fail.cpp
@@ -0,0 +1,194 @@
+/*
+ * Copyright (C) 2021 Open Source Robotics Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+*/
+
+#include <rmf_utils/catch.hpp>
+#include <rmf_traffic/agv/VehicleTraits.hpp>
+#include <rmf_traffic/geometry/Circle.hpp>
+#include <rmf_traffic/DetectConflict.hpp>
+
+#include <fstream>
+
+namespace {
+
+class SerializedWaypoint
+{
+public:
+  Eigen::Vector3d position, velocity;
+
+  rmf_traffic::Time time;
+};
+
+SerializedWaypoint read_waypoint(const std::string& file_name)
+{
+  std::ifstream file;
+  file.open(file_name, std::ios::in);
+  SerializedWaypoint serialized_waypoint;
+  file.seekg(0);
+  file.read((char*)&serialized_waypoint, sizeof(SerializedWaypoint));
+  file.close();
+  return serialized_waypoint;
+}
+
+void write_waypoint(const std::string& file_name,
+  SerializedWaypoint& serialized_waypoint)
+{
+  std::ofstream file;
+  file.open(file_name, std::ios::out);
+  file.write((char*) &serialized_waypoint, sizeof(SerializedWaypoint));
+  file.close();
+}
+
+//==============================================================================
+SCENARIO("Failed Detect Conflict")
+{
+  SerializedWaypoint serialized_waypoint[4];
+  serialized_waypoint[0] =
+    read_waypoint(RESOURCES_DIR + std::string("/Waypoint5.txt"));
+  serialized_waypoint[1] =
+    read_waypoint(RESOURCES_DIR + std::string("/Waypoint6.txt"));
+  serialized_waypoint[2] =
+    read_waypoint(RESOURCES_DIR + std::string("/Waypoint7.txt"));
+  serialized_waypoint[3] =
+    read_waypoint(RESOURCES_DIR + std::string("/Waypoint8.txt"));
+
+  rmf_traffic::agv::VehicleTraits traits{
+    {0.5, 2.0}, {0.75, 1.5},
+    rmf_traffic::Profile{
+      rmf_traffic::geometry::make_final_convex(
+        rmf_traffic::geometry::Circle(0.2))
+    }
+  };
+
+  rmf_traffic::Trajectory traj1, traj2;
+  traj1.insert(
+    serialized_waypoint[0].time,
+    serialized_waypoint[0].position,
+    serialized_waypoint[0].velocity);
+  traj1.insert(
+    serialized_waypoint[1].time,
+    serialized_waypoint[1].position,
+    serialized_waypoint[1].velocity);
+
+  traj2.insert(
+    serialized_waypoint[2].time,
+    serialized_waypoint[2].position,
+    serialized_waypoint[2].velocity);
+  traj2.insert(
+    serialized_waypoint[3].time,
+    serialized_waypoint[3].position,
+    serialized_waypoint[3].velocity);
+
+  bool detect_conflict =
+    rmf_traffic::DetectConflict::between(traits.profile(),
+      traj1,
+      traits.profile(),
+      traj2).has_value();
+
+  CHECK(detect_conflict);
+}
+
+//==============================================================================
+SCENARIO("Rotation failure")
+{
+  SerializedWaypoint serialized_waypoint[4];
+  serialized_waypoint[0] =
+    read_waypoint(RESOURCES_DIR + std::string("/Waypoint1.txt"));
+  serialized_waypoint[1] =
+    read_waypoint(RESOURCES_DIR + std::string("/Waypoint2.txt"));
+  serialized_waypoint[2] =
+    read_waypoint(RESOURCES_DIR + std::string("/Waypoint3.txt"));
+  serialized_waypoint[3] =
+    read_waypoint(RESOURCES_DIR + std::string("/Waypoint4.txt"));
+
+  rmf_traffic::agv::VehicleTraits traits{
+    {0.5, 2.0}, {0.75, 1.5},
+    rmf_traffic::Profile{
+      rmf_traffic::geometry::make_final_convex(
+        rmf_traffic::geometry::Circle(0.2))
+    }
+  };
+
+  rmf_traffic::Trajectory traj1, traj2;
+  traj1.insert(
+    serialized_waypoint[0].time,
+    serialized_waypoint[0].position,
+    serialized_waypoint[0].velocity);
+  traj1.insert(
+    serialized_waypoint[1].time,
+    serialized_waypoint[1].position,
+    serialized_waypoint[1].velocity);
+
+  traj2.insert(
+    serialized_waypoint[2].time,
+    serialized_waypoint[2].position,
+    serialized_waypoint[2].velocity);
+  traj2.insert(
+    serialized_waypoint[3].time,
+    serialized_waypoint[3].position,
+    serialized_waypoint[3].velocity);
+
+  bool detect_conflict_with_rotation =
+    rmf_traffic::DetectConflict::between(traits.profile(),
+      traj1,
+      traits.profile(),
+      traj2).has_value();
+
+  rmf_traffic::Trajectory traj3, traj4;
+  traj3.insert(
+    serialized_waypoint[0].time,
+    {serialized_waypoint[0].position.x(),
+      serialized_waypoint[0].position.y(),
+      0.0},
+    {serialized_waypoint[0].velocity.x(),
+      serialized_waypoint[0].velocity.y(),
+      0.0});
+  traj3.insert(
+    serialized_waypoint[1].time,
+    {serialized_waypoint[1].position.x(),
+      serialized_waypoint[1].position.y(),
+      0.0},
+    {serialized_waypoint[1].velocity.x(),
+      serialized_waypoint[1].velocity.y(),
+      0.0});
+
+  traj4.insert(
+    serialized_waypoint[2].time,
+    {serialized_waypoint[2].position.x(),
+      serialized_waypoint[2].position.y(),
+      0.0},
+    {serialized_waypoint[2].velocity.x(),
+      serialized_waypoint[2].velocity.y(),
+      0.0});
+  traj4.insert(
+    serialized_waypoint[3].time,
+    {serialized_waypoint[3].position.x(),
+      serialized_waypoint[3].position.y(),
+      0.0},
+    {serialized_waypoint[3].velocity.x(),
+      serialized_waypoint[3].velocity.y(),
+      0.0});
+
+
+  bool detect_conflict_without_rotation =
+    rmf_traffic::DetectConflict::between(traits.profile(),
+      traj3,
+      traits.profile(),
+      traj4).has_value();
+
+  CHECK(detect_conflict_with_rotation == detect_conflict_without_rotation);
+}
+}
\ No newline at end of file
diff --git a/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint1.txt b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint1.txt
new file mode 100644
index 00000000..2d2e54be
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diff --git a/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint2.txt b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint2.txt
new file mode 100644
index 00000000..20253979
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diff --git a/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint3.txt b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint3.txt
new file mode 100644
index 00000000..4dff3acc
Binary files /dev/null and b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint3.txt differ
diff --git a/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint4.txt b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint4.txt
new file mode 100644
index 00000000..fcbf3f02
Binary files /dev/null and b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint4.txt differ
diff --git a/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint5.txt b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint5.txt
new file mode 100644
index 00000000..83b97b8a
Binary files /dev/null and b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint5.txt differ
diff --git a/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint6.txt b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint6.txt
new file mode 100644
index 00000000..f1090fec
Binary files /dev/null and b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint6.txt differ
diff --git a/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint7.txt b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint7.txt
new file mode 100644
index 00000000..991ff44d
Binary files /dev/null and b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint7.txt differ
diff --git a/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint8.txt b/rmf_traffic/test/resources/regress_DetectConflict_fail/Waypoint8.txt
new file mode 100644
index 00000000..f8e373e2
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