search

ros-controls / ros2_control

Generic and simple controls framework for ROS 2
https://control.ros.org
Apache License 2.0
512 stars 304 forks source link

Is it possible to implement event-driven control within the ROS 2 Control framework? #1578

Open lkx8421 opened 5 months ago

lkx8421 commented 5 months ago

I am currently facing a problem with my feedback control system: the feedback sensor data is obtained through subscribing to topics and is assigned to the hardware interface. When I launch the control, there is a slight delay between the actual control computation start and the sensor timestamp (the control frequency is 500 Hz, which means the control computation may start 0-2ms later than the sensor timestamp). Here is the topic timestamp and control start timestamp. 图片

图片

Have you ever encountered a similar problem? If so, how did you solve it? Looking forward to your reply!

christophfroehlich commented 5 months ago

Can you give more details about the signal paths? You have written a custom hardware component, which is subscribing to topics and publishing them again?

lkx8421 commented 5 months ago

Thank you for your reply. Indeed, I assigned values to the hardware component by subscribing to the motors information. These signals are for displaying the information of the three groups of sensors I subscribed to and the timestamp at the start of control (the blue straight line). I can't specify that the control starts to be executed immediately after the three topics are actually received, it is executed after an uncertain period of delay.