diff --git a/src/examples/maps/map_apriltag_logitech_1234.yaml b/src/examples/maps/map_apriltag_logitech_1234.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..850c04adf9e76e6588cae936acb5086d4caf51e0
--- /dev/null
+++ b/src/examples/maps/map_apriltag_logitech_1234.yaml
@@ -0,0 +1,46 @@
+map name: "4 tags printed on a A4 sheet vertical recorded at IRI with logitech webcam."
+
+nlandmarks: 4          # This must match the number of landmarks in the list that follows. Otherwise it is an error.
+
+######################
+# World frame is considered to be at 75cm from the sheet with RDF convention (like a camera). 
+# Landmarks facing the Z axis (view axis of the camera) have the same orientation as world frame.
+######################
+landmarks:
+
+  - id : 0                    # use same as tag id
+    type: "APRILTAG"          # This must match the KEY used in the LandmarkFactory. Otherwise it is an error.
+    tag id: 0
+    tag width: 0.055
+    position: [-0.061, -0.185, 0.75]
+    orientation: [0, 0, 0]    # roll pitch yaw in degrees
+    position fixed: true
+    orientation fixed: true
+
+  - id : 1                    # use same as tag id
+    type: "APRILTAG"          # This must match the KEY used in the LandmarkFactory. Otherwise it is an error.
+    tag id: 1
+    tag width: 0.055
+    position: [0.061, -0.185, 0.75]
+    orientation: [0, 0, 0]    # roll pitch yaw in degrees
+    position fixed: true
+    orientation fixed: true
+
+  - id : 2                    # use same as tag id
+    type: "APRILTAG"          # This must match the KEY used in the LandmarkFactory. Otherwise it is an error.
+    tag id: 2
+    tag width: 0.055
+    position: [-0.061, 0, 0.75]
+    orientation: [0, 0, 0]    # roll pitch yaw in degrees
+    position fixed: true
+    orientation fixed: true
+
+  - id : 3                    # use same as tag id
+    type: "APRILTAG"          # This must match the KEY used in the LandmarkFactory. Otherwise it is an error.
+    tag id: 3
+    tag width: 0.055
+    position: [0.061, 0, 0.75]
+    orientation: [0, 0, 0]    # roll pitch yaw in degrees
+    position fixed: true
+    orientation fixed: true
+
diff --git a/src/examples/test_apriltag.cpp b/src/examples/test_apriltag.cpp
index 7366b72586df604d5d96fffeba5e1afcf3f3c5e9..b6081b0843aa601bce2ce4862aefdf93a7f43d95 100644
--- a/src/examples/test_apriltag.cpp
+++ b/src/examples/test_apriltag.cpp
@@ -59,14 +59,17 @@ int main(int argc, char *argv[])
     SensorCameraPtr sen_cam = std::static_pointer_cast<SensorCamera>(sen);
     ProcessorBasePtr prc    = problem->installProcessor("TRACKER LANDMARK APRILTAG", "apriltags", "camera", wolf_root + "/src/examples/processor_tracker_landmark_apriltag.yaml");
 
+    std::cout << wolf_root + "/src/examples/maps/map_apriltag_logitech.yaml" << std::endl;
+    problem->loadMap(wolf_root + "/src/examples/maps/map_apriltag_logitech_1234.yaml");
+
     // set prior
     Eigen::Matrix6s covariance = Matrix6s::Identity();
     Scalar stdev_m   = 0.00001;  // standard deviation on original translation
     Scalar stdev_deg = 0.00001;  // standard deviation on original rotation
     covariance.topLeftCorner(3,3)       =  stdev_m*stdev_m * covariance.topLeftCorner(3,3);
     covariance.bottomRightCorner(3,3)   = (M_TORAD*stdev_deg)*(M_TORAD*stdev_deg) * covariance.bottomRightCorner(3,3);
-    FrameBasePtr F1 = problem->setPrior((Vector7s()<<0,0,0,0,0,0,1).finished(), covariance, 0.0, 0.1);
 
+    FrameBasePtr F1 = problem->setPrior((Vector7s()<<0,0,0,0,0,0,1).finished(), covariance, 0.0, 0.1);
 
     // first argument is the name of the program.
     // following arguments are path to image (from wolf_root)