diff --git a/rednose/__init__.py b/rednose/__init__.py
index a221424..447100a 100644
--- a/rednose/__init__.py
+++ b/rednose/__init__.py
@@ -4,12 +4,18 @@ from rednose.helpers.ekf_sym import EKF_sym
 
 
 class KalmanFilter:
+  name = None
+  initial_x = None
+  initial_P_diag = None
+  Q = None
+  obs_noise = None
+
   def __init__(self, generated_dir):
-    self.dim_state = self.initial_x.shape[0]
-    self.dim_state_err = self.initial_P_diag.shape[0]
+    dim_state = self.initial_x.shape[0]
+    dim_state_err = self.initial_P_diag.shape[0]
 
     # init filter
-    self.filter = EKF_sym(generated_dir, self.name, self.Q, self.initial_x, np.diag(self.initial_P_diag), self.dim_state, self.dim_state_err)
+    self.filter = EKF_sym(generated_dir, self.name, self.Q, self.initial_x, np.diag(self.initial_P_diag), dim_state, dim_state_err)
 
   @property
   def x(self):