TypeError: unsupported operand type(s) for -: 'NoneType' and 'int'**

[1991dhanraj]

Hi,
When i run the roboclaw ros package to control the speed of the motor i get the following error.

File "/home/dhanraj/catkin_ws/src/roboclaw_ros/roboclaw_node/nodes/roboclaw_node.py", line 77, in ## update_publish
if abs(enc_left - self.last_enc_left) > 20000:
TypeError: unsupported operand type(s) for -: 'NoneType' and 'int'
[roboclaw_node-1] process has died [pid 10701, exit code 1, cmd /home/dhanraj/catkin_ws/src/roboclaw_ros/roboclaw_node/nodes/roboclaw_node.py __name:=roboclaw_node __log:=/home/dhanraj/.ros/log/576dcfaa-ebe6-11e7-9751-74e543172118/roboclaw_node-1.log].
log file: /home/dhanraj/.ros/log/576dcfaa-ebe6-11e7-9751-74e543172118/roboclaw_node-1*.log

When i run the scripts the motors does not movie at all and i get the above error after the script has run for couple of minutes. Any help on this is appreciated.

regards
Dhanraj

[vishu2287]

@1991dhanraj . did you solve this? if so can you share your solution?

[DariusStu]

Has any solution been found for this?