diff --git a/robomaster_pi/conn_vel.py b/robomaster_pi/conn_vel.py
index 9b10ec18226ec30c69c8ab5ab32d17584e1af79f..96ef07915004714dc4e1ee5e9858d1ff59d393a6 100644
--- a/robomaster_pi/conn_vel.py
+++ b/robomaster_pi/conn_vel.py
@@ -2,7 +2,7 @@ import robomaster
 from robomaster import robot
 import math
 import time
-from threading 
+import threading 
 import numpy as np
 import rclpy
 from rclpy.node import Node