diff --git a/src/arm_pkg/arm_pkg/arm_node.py b/src/arm_pkg/arm_pkg/arm_node.py
index d394e8a..10c7fdc 100644
--- a/src/arm_pkg/arm_pkg/arm_node.py
+++ b/src/arm_pkg/arm_pkg/arm_node.py
@@ -35,12 +35,12 @@ viccan_socket_msg_len_dict = {
     54: 4,
     55: 4,
     58: 4,
-    59: 4
+    59: 4,
 }
 viccan_digit_msg_len_dict = {
     54: 4,
     55: 2,
-    59: 2
+    59: 2,
 }
 
 
@@ -80,10 +80,16 @@ class SerialRelay(Node):
 
         # Feedback
 
-        self.arm_feedback_pub_ = self.create_publisher(ArmFeedback, "/arm/feedback/new_feedback", qos_profile=qos.qos_profile_sensor_data)
+        self.arm_feedback_pub_ = self.create_publisher(
+            ArmFeedback,
+            "/arm/feedback/new_feedback",
+            qos_profile=qos.qos_profile_sensor_data,
+        )
         self.arm_feedback_new = ArmFeedback()
         # IK: /joint_states is published from here to topic_based_control
-        self.joint_state_pub_ = self.create_publisher(JointState, "joint_states", qos_profile=qos.qos_profile_sensor_data)
+        self.joint_state_pub_ = self.create_publisher(
+            JointState, "joint_states", qos_profile=qos.qos_profile_sensor_data
+        )
         self.saved_joint_state = JointState()
         self.saved_joint_state.name = [
             "Axis_0_Joint",
@@ -202,13 +208,15 @@ class SerialRelay(Node):
             pass
 
     def joint_command_callback(self, msg: JointState):
-        if len(msg.position) < 7 and len(msg.velocity) < 7:  # one or the other needs to be filled
-            return
+        if len(msg.position) < 7 and len(msg.velocity) < 7:
+            return  # command needs either position or velocity for all 7 joints
 
         # Assumed order: Axis0, Axis1, Axis2, Axis3, Wrist_Yaw, Wrist_Roll, Gripper
         # TODO: formalize joint names in URDF, refactor here to depend on joint names
         # Embedded takes deg*10, ROS2 uses Radians
-        velocities = [math.degrees(vel) * 10 if abs(vel) > 0.05 else 0.0 for vel in msg.velocity]
+        velocities = [
+            math.degrees(vel) * 10 if abs(vel) > 0.05 else 0.0 for vel in msg.velocity
+        ]
         # Axis 2 & 3 URDF direction is inverted
         velocities[2] = -velocities[2]
         velocities[3] = -velocities[3]
@@ -289,7 +297,7 @@ class SerialRelay(Node):
             self.process_fromvic_arm(msg)
         elif msg.mcu_name == "digit":
             self.process_fromvic_digit(msg)
-    
+
     def process_fromvic_arm(self, msg: VicCAN):
         if msg.mcu_name != "arm":
             return
@@ -322,7 +330,7 @@ class SerialRelay(Node):
                     motor.voltage = float(msg.data[2]) / 10.0
                     motor.current = float(msg.data[3]) / 10.0
                     motor.header.stamp = msg.header.stamp
-                
+
                 self.arm_feedback_pub_.publish(self.arm_feedback_new)
             case 54:  # Board voltages
                 self.arm_feedback_new.socket_voltage.vbatt = float(msg.data[0]) / 100.0
@@ -334,8 +342,12 @@ class SerialRelay(Node):
                 # Joint state publisher for URDF visualization
                 self.saved_joint_state.position[0] = math.radians(angles[0])  # Axis 0
                 self.saved_joint_state.position[1] = math.radians(angles[1])  # Axis 1
-                self.saved_joint_state.position[2] = math.radians(-angles[2])  # Axis 2 (inverted)
-                self.saved_joint_state.position[3] = math.radians(-angles[3])  # Axis 3 (inverted)
+                self.saved_joint_state.position[2] = math.radians(
+                    -angles[2]
+                )  # Axis 2 (inverted)
+                self.saved_joint_state.position[3] = math.radians(
+                    -angles[3]
+                )  # Axis 3 (inverted)
                 # Wrist is handled by digit feedback
                 self.saved_joint_state.header.stamp = msg.header.stamp
                 self.joint_state_pub_.publish(self.saved_joint_state)
@@ -351,7 +363,7 @@ class SerialRelay(Node):
                         motor = self.arm_feedback_new.axis3_motor
                     case 4:
                         motor = self.arm_feedback_new.axis0_motor
-                
+
                 if motor:
                     motor.position = float(msg.data[1])
                     motor.velocity = float(msg.data[2])
@@ -360,10 +372,18 @@ class SerialRelay(Node):
                 self.arm_feedback_pub_.publish(self.arm_feedback_new)
             case 59:  # Arm joint velocities
                 velocities = [vel / 100.0 for vel in msg.data]  # VicCAN sends deg/s*100
-                self.saved_joint_state.velocity[0] = math.radians(velocities[0])  # Axis 0
-                self.saved_joint_state.velocity[1] = math.radians(velocities[1])  # Axis 1
-                self.saved_joint_state.velocity[2] = math.radians(-velocities[2])  # Axis 2 (-)
-                self.saved_joint_state.velocity[3] = math.radians(-velocities[3])  # Axis 3 (-)
+                self.saved_joint_state.velocity[0] = math.radians(
+                    velocities[0]
+                )  # Axis 0
+                self.saved_joint_state.velocity[1] = math.radians(
+                    velocities[1]
+                )  # Axis 1
+                self.saved_joint_state.velocity[2] = math.radians(
+                    -velocities[2]
+                )  # Axis 2 (-)
+                self.saved_joint_state.velocity[3] = math.radians(
+                    -velocities[3]
+                )  # Axis 3 (-)
                 # Wrist is handled by digit feedback
                 self.saved_joint_state.header.stamp = msg.header.stamp
                 self.joint_state_pub_.publish(self.saved_joint_state)
@@ -387,8 +407,12 @@ class SerialRelay(Node):
                 self.arm_feedback_new.digit_voltage.v12 = float(msg.data[1]) / 100.0
                 self.arm_feedback_new.digit_voltage.v5 = float(msg.data[2]) / 100.0
             case 55:  # Arm joint positions
-                self.saved_joint_state.position[4] = math.radians(msg.data[0])  # Wrist roll
-                self.saved_joint_state.position[5] = math.radians(msg.data[1])  # Wrist yaw
+                self.saved_joint_state.position[4] = math.radians(
+                    msg.data[0]
+                )  # Wrist roll
+                self.saved_joint_state.position[5] = math.radians(
+                    msg.data[1]
+                )  # Wrist yaw
 
     def publish_feedback(self):
         self.socket_pub.publish(self.arm_feedback)