diff --git a/dex_retargeting/optimizer.py b/dex_retargeting/optimizer.py
index fdc606e..f8d3eb7 100644
--- a/dex_retargeting/optimizer.py
+++ b/dex_retargeting/optimizer.py
@@ -314,21 +314,14 @@ def __init__(
         eta2=3e-2,
         scaling=1.0,
     ):
-        # if len(finger_tip_link_names) < 4 or len(finger_tip_link_names) > 5:
-        #     raise ValueError(f"DexPilot optimizer can only be applied to hands with four or five fingers")
+        if len(finger_tip_link_names) < 2 or len(finger_tip_link_names) > 5:
+            raise ValueError(
+                f"DexPilot optimizer can only be applied to hands with 2 to 5 fingers, but got "
+                f"{len(finger_tip_link_names)} fingers."
+            )
         self.num_fingers = len(finger_tip_link_names)
 
-        if self.num_fingers == 2:  # For gripper
-            origin_link_index = [2, 0, 0]
-            task_link_index = [1, 1, 2]
-        elif self.num_fingers == 4:
-            origin_link_index = [2, 3, 4, 3, 4, 4, 0, 0, 0, 0]
-            task_link_index = [1, 1, 1, 2, 2, 3, 1, 2, 3, 4]
-        elif self.num_fingers == 5:
-            origin_link_index = [2, 3, 4, 5, 3, 4, 5, 4, 5, 5, 0, 0, 0, 0, 0]
-            task_link_index = [1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 1, 2, 3, 4, 5]
-        else:
-            raise NotImplementedError(f"Unsupported number of fingers: {self.num_fingers}")
+        origin_link_index, task_link_index = self.generate_link_indices(self.num_fingers)
 
         if target_link_human_indices is None:
             target_link_human_indices = (np.stack([origin_link_index, task_link_index], axis=0) * 4).astype(int)
@@ -363,23 +356,55 @@ def __init__(
         self.opt.set_ftol_abs(1e-6)
 
         # DexPilot cache
-        if self.num_fingers == 2:
-            self.projected = np.zeros(1, dtype=bool)
-            self.s2_project_index_origin = np.array([], dtype=int)
-            self.s2_project_index_task = np.array([], dtype=int)
-            self.projected_dist = np.array([eta1] * 1)
-        elif self.num_fingers == 4:
-            self.projected = np.zeros(6, dtype=bool)
-            self.s2_project_index_origin = np.array([1, 2, 2], dtype=int)
-            self.s2_project_index_task = np.array([0, 0, 1], dtype=int)
-            self.projected_dist = np.array([eta1] * 3 + [eta2] * 3)
-        elif self.num_fingers == 5:
-            self.projected = np.zeros(10, dtype=bool)
-            self.s2_project_index_origin = np.array([1, 2, 3, 2, 3, 3], dtype=int)
-            self.s2_project_index_task = np.array([0, 0, 0, 1, 1, 2], dtype=int)
-            self.projected_dist = np.array([eta1] * 4 + [eta2] * 6)
-        else:
-            raise NotImplementedError(f"Unsupported number of fingers: {self.num_fingers}")
+        self.projected, self.s2_project_index_origin, self.s2_project_index_task, self.projected_dist = (
+            self.set_dexpilot_cache(self.num_fingers, eta1, eta2)
+        )
+
+    @staticmethod
+    def generate_link_indices(num_fingers):
+        """
+        Example:
+        >>> generate_link_indices(4)
+        ([2, 3, 4, 3, 4, 4, 0, 0, 0, 0], [1, 1, 1, 2, 2, 3, 1, 2, 3, 4])
+        """
+        origin_link_index = []
+        task_link_index = []
+
+        # Add indices for connections between fingers
+        for i in range(1, num_fingers):
+            for j in range(i + 1, num_fingers + 1):
+                origin_link_index.append(j)
+                task_link_index.append(i)
+
+        # Add indices for connections to the base (0)
+        for i in range(1, num_fingers + 1):
+            origin_link_index.append(0)
+            task_link_index.append(i)
+
+        return origin_link_index, task_link_index
+
+    @staticmethod
+    def set_dexpilot_cache(num_fingers, eta1, eta2):
+        """
+        Example:
+        >>> set_dexpilot_cache(4, 0.1, 0.2)
+        (array([False, False, False, False, False, False]),
+        [1, 2, 2],
+        [0, 0, 1],
+        array([0.1, 0.1, 0.1, 0.2, 0.2, 0.2]))
+        """
+        projected = np.zeros(num_fingers * (num_fingers - 1) // 2, dtype=bool)
+
+        s2_project_index_origin = []
+        s2_project_index_task = []
+        for i in range(0, num_fingers - 2):
+            for j in range(i + 1, num_fingers - 1):
+                s2_project_index_origin.append(j)
+                s2_project_index_task.append(i)
+
+        projected_dist = np.array([eta1] * (num_fingers - 1) + [eta2] * ((num_fingers - 1) * (num_fingers - 2) // 2))
+
+        return projected, s2_project_index_origin, s2_project_index_task, projected_dist
 
     def get_objective_function(self, target_vector: np.ndarray, fixed_qpos: np.ndarray, last_qpos: np.ndarray):
         qpos = np.zeros(self.num_joints)
diff --git a/example/vector_retargeting/capture_webcam.py b/example/vector_retargeting/capture_webcam.py
index e3de15d..ac09c4b 100644
--- a/example/vector_retargeting/capture_webcam.py
+++ b/example/vector_retargeting/capture_webcam.py
@@ -30,7 +30,7 @@ def main(video_path: str, video_capture_device: Union[str, int] = 0):
         if cv2.waitKey(1) & 0xFF == 27:
             break
 
-    print('Recording finished')
+    print("Recording finished")
     cap.release()
     writer.release()
     cv2.destroyAllWindows()
diff --git a/setup.py b/setup.py
index 910a505..8e5a66d 100644
--- a/setup.py
+++ b/setup.py
@@ -107,7 +107,7 @@ def setup_package():
         python_requires=">=3.7,<3.11",
         zip_safe=True,
         include_package_data=True,
-        package_data={'dex_retargeting': ['configs/**']},
+        package_data={"dex_retargeting": ["configs/**"]},
         install_requires=core_requirements,
         extras_require={
             "dev": dev_requirements,