[ros-users] launch node at runtime

I have a large system with many nodes for specific purposes. At any
given time, many nodes do not need to be running. I would like to be
able to start a node from my master rospy code when it determines it
needs that node up. I think actually launching the node is as easy as
an os.system call. However, I would like to interface with the newly
started node, and would like it if I did not have to list every package
in the master's manifest. Basically, I would like to take a string
names for a package / node / etc., then at runtime load it into my
manifest, then be able to set up a publisher and subscriber to it.



Here are some questions.

1.      Has anyone done this type of thing before?

2.      Do you have any input on best practices?

3.      It seems like part of the answer is some sort of standard
interface (or a standard interface to determine what the actual
interface to that node is).  Any ideas on this?

4.      Is there anything more elegant that a bunch of eval() statements
(to turn string names into message types)?

5.      What would I need to do to load a package into my manifest at
runtime?  Do the dependencies in a manifest simply get turned into paths
in the PYTHONPATH?

Thanks,

-Ben



Ben Axelrod

Research Scientist

iRobot Corporation

8 Crosby Drive, Mail Stop 8-1

Bedford, MA 01730

(781) 430-3315 (Tel)

(781) 960-2628 (Fax)

baxelrod@irobot.com <mailto:ofitch@irobot.com>