ros_arduino_bridge reconnection error

edit

Hi, when I

• launch the "ros_arduino_python/arduino.launch"

I can perfectly control the base using "teleop_twist_keyboard" which is publishing the cmd_vel topic.

But When I shutdown the arduino.launch by pressing ctrl+c *and try to launch the ros_arduino_python/arduino.launch again, *I see the connection Exception. as below:

===============

Connecting to Arduino on port /dev/ARDUINOBASE ...
Serial Exception:
(<class 'serial.serialutil.SerialException'>, SerialException(), <traceback object at 0xb5f57a80>)
Traceback follows:
Traceback (most recent call last):
File "/root/catkin_ws/src/ros_arduino_bridge/ros_arduino_python/src/ros_arduino_python/arduino_driver.py", line 73, in connect
raise SerialException
SerialException
Cannot connect to Arduino!

=================

The error log is below:

root@pirobot:~# roslaunch ros_arduino_python arduino.launch
... logging to /root/.ros/log/8e8d6d00-9f12-11e6-b069-28f3667b4dc0/roslaunch-pirobot-2919.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://pirobot:37235/

SUMMARY
========

PARAMETERS
 * /arduino/Kd: 12
 * /arduino/Ki: 0
 * /arduino/Ko: 50
 * /arduino/Kp: 10
 * /arduino/accel_limit: 1.0
 * /arduino/base_controller_rate: 10
 * /arduino/base_frame: base_link
 * /arduino/baud: 57600
  * /arduino/encoder_resolution: 2200
  * /arduino/gear_reduction: 1.0
  * /arduino/motors_reversed: False
  * /arduino/port: /dev/ARDUINOBASE
  * /arduino/rate: 50
  * /arduino/sensors/arduino_led/direction: output
  * /arduino/sensors/arduino_led/pin: 13
  * /arduino/sensors/arduino_led/rate: 5
  * /arduino/sensors/arduino_led/type: Digital
  * /arduino/sensorstate_rate: 10
  * /arduino/timeout: 0.1
  * /arduino/use_base_controller: True
  * /arduino/wheel_diameter: 0.08
  * /arduino/wheel_track: 0.36
  * /rosdistro: indigo
  * /rosversion: 1.11.20

 NODES
 /
 arduino (ros_arduino_python/arduino_node.py)

 ROS_MASTER_URI=http://pirobot:11311

 core service [/rosout] found
 process[arduino-1]: started with pid [2937]
 Connecting to Arduino on port /dev/ARDUINOBASE ...
 Serial Exception:
 (<class 'serial.serialutil.SerialException'>, SerialException(), <traceback object at 0xb5f57a80>)
 Traceback follows:
 Traceback (most recent call last):
 File "/root/catkin_ws/src/ros_arduino_bridge/ros_arduino_python/src/ros_arduino_python/arduino_driver.py", line 73, in connect
 raise SerialException
 SerialException
 Cannot connect to Arduino!
 [arduino-1] process has died [pid 2937, exit code 1, cmd /root/catkin_ws/src/ros_arduino_bridge/ros_arduino_python/nodes/arduino_node.py __name:=arduino __log:=/root/.ros/log/8e8d6d00-9f12-11e6-b069-28f3667b4dc0/arduino-1.log].
 log file: /root/.ros/log/8e8d6d00-9f12-11e6-b069-28f3667b4dc0/arduino-1*.log
 all processes on machine have died, roslaunch will exit
 shutting down processing monitor...
 ... shutting down processing monitor complete
 done