diff --git a/ArmNavigation/n_joint_arm_3d/NLinkArm3d.py b/ArmNavigation/n_joint_arm_3d/NLinkArm3d.py
index 0cea963168..0459e234b2 100644
--- a/ArmNavigation/n_joint_arm_3d/NLinkArm3d.py
+++ b/ArmNavigation/n_joint_arm_3d/NLinkArm3d.py
@@ -127,7 +127,8 @@ def inverse_kinematics(self, ref_ee_pose, plot=False):
 
         if plot:
             self.fig = plt.figure()
-            self.ax = Axes3D(self.fig)
+            self.ax = Axes3D(self.fig, auto_add_to_figure=False)
+            self.fig.add_axes(self.ax)
 
             x_list = []
             y_list = []
diff --git a/Localization/particle_filter/particle_filter.py b/Localization/particle_filter/particle_filter.py
index 17051623ca..ba54a3d12b 100644
--- a/Localization/particle_filter/particle_filter.py
+++ b/Localization/particle_filter/particle_filter.py
@@ -96,10 +96,10 @@ def calc_covariance(x_est, px, pw):
     calculate covariance matrix
     see ipynb doc
     """
-    cov = np.zeros((3, 3))
+    cov = np.zeros((4, 4))
     n_particle = px.shape[1]
     for i in range(n_particle):
-        dx = (px[:, i:i + 1] - x_est)[0:3]
+        dx = (px[:, i:i + 1] - x_est)
         cov += pw[0, i] * dx @ dx.T
     cov *= 1.0 / (1.0 - pw @ pw.T)
 
diff --git a/requirements/requirements.txt b/requirements/requirements.txt
index 8e4d166c4e..0575353a11 100644
--- a/requirements/requirements.txt
+++ b/requirements/requirements.txt
@@ -2,7 +2,7 @@ numpy == 1.26.4
 scipy == 1.13.0
 matplotlib == 3.8.4
 cvxpy == 1.4.3
-pytest == 8.1.1 # For unit test
-pytest-xdist == 3.5.0 # For unit test
-mypy == 1.9.0 # For unit test
-ruff == 0.4.1 # For unit test
+pytest == 8.2.0 # For unit test
+pytest-xdist == 3.6.1 # For unit test
+mypy == 1.10.0 # For unit test
+ruff == 0.4.2 # For unit test