UnicodeEncodeError while running roslaunch (kinetic)

Hi there, I'm very new to ROS. I'm trying to connect my lidar (EAI ydlidar X4) with hector mapping, and downloaded from git clone https://github.com/tu-darmstadt-ros-pkg/hector_slam I've created a launch file (from tutorial online): however, when I roslaunch it, I got: Checking log directory for disk usage. This may take awhile. Press Ctrl-C to interrupt Done checking log file disk usage. Usage is <1GB. 'ascii' codec can't encode character u'\xa0' in position 0: ordinal not in range(128) The traceback for the exception was written to the log file and in the log: ....... File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/substitution_args.py", line 365, in resolve_args resolved = _resolve_args(arg_str, context, resolve_anon, commands) File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/substitution_args.py", line 376, in _resolve_args for a in _collect_args(arg_str): File "/opt/ros/kinetic/lib/python2.7/dist-packages/roslaunch/substitution_args.py", line 434, in _collect_args buff.write(c) UnicodeEncodeError: 'ascii' codec can't encode character u'\xa0' in position 0: ordinal not in range(128) [rospy.core][INFO] 2018-10-03 12:28:17,248: signal_shutdown [atexit] Anyone knows how to solve this?