Why is ROS not a real-time operating system?

Question

ROS is not real-time OS. After reading the architecture of ROS, I am unable to realize why is ROS not real-time? What part of the architecture or what design decision is causing that?

Just as a reference; the same topic on ROS side http://answers.ros.org/question/134551/why-is-ros-not-real-time/ — IsaacS, Mar 01 '14 at 12:43

score 2 · Answer 1 · answered Mar 01 '14 at 01:56

2

Check out this website, http://www.control.com/thread/1026205354 you'll find your answer. The reason I directed you to this website is because ROS is an Operating System to provide Real-Time like operation but not truly. You can also call it as Pseudo-RTOS.

answered Mar 01 '14 at 01:56

Tvaṣṭā

421
2
11

I am expecting an answer particular to the implementation of ROS. – Manas Paldhe Mar 01 '14 at 03:00
1

Implementation as in ? :/ – Tvaṣṭā Mar 01 '14 at 03:03
implementation as in, what particular part of ROS is the cause for it not being RT? – Manas Paldhe Mar 02 '14 at 10:24
I found that it used TCP for communication and so is not RT – Manas Paldhe Mar 02 '14 at 10:25
@Tvaṣṭā Thanks for the very informative link. However, is there a chance you can summarise the most salient points from that discussion? This helps prevent link rot and ensures people take the right answer away from this question. – ThomasH Mar 04 '14 at 19:12

score 2 · Answer 2 · answered Mar 01 '14 at 06:31

ROS isn't even an operating system, it's a framework and it's usually built on top of Ubuntu. First and foremost, it provides a clean way to write several modular programs with inputs and outputs and stitch them together at runtime.

There's no reason you can't run ROS inside a RTOS (however, it was developed on Ubuntu, so it will take effort to get it running on anything else.)

Why is ROS not a real-time operating system?

2 Answers2