Action Feedback is not publishing at 1 Hz

[bayodesegun]

Hi @nrjbs87, the Rate object is useless outside a loop:

Proper use of rospy.Rate or ros::Rate

Background I created this topic because I frequently come across the use of rospy.Rate (ROS Python) and ros::Rate (ROS C++) in places where they are not needed. By the way, what is this Rate thingy? According to ROS Wiki, rospy.Rate and ros::Rate are convenience classes that make a best effort at maintaining a particular rate for a loop. For example: // C++ example ros::Rate r(10); // 10 hz while (ros::ok()) { // ... do some work ... r.sleep(); } # Python example r = rospy.Rate(10) # …

For things to work as expected,

• you need to publish the feedback in a loop.
• self.rate.sleep() will need to be in the loop as well.

Something like:

# be careful here: don't use a condition that will never be false
# otherwise your action will never finish!
while some_condition_is_true:  
    self._feedback.feedback = command
    self._as.publish_feedback(self._feedback)
    self.rate.sleep()

That said, I don’t think publishing the feedback every second will work out of the box though, because the whole action will be completed in probably less than a second. Of course, you can intentionally make the action last longer just to have some fun!