Feature Request: CRTK-ROS bridge required interfaces

[htp2]

It would be useful to extend the crtk_cisst_ros_bridge to also allow for easy bridging of required interfaces, similar to the current one-liners for provided interfaces we have currently: (bridge_interface_provided and bridge_all_interface_provided)

I would be able to use this immediately in my work (though I can work without it just fine for now), and would be willing to help with testing and development to the extent that I would be useful. I think it would greatly increase the usability of the cisst-ros bridge for a lot of users and encourage the use of CRTK conventions, both of which are really good things from my perspective.

I understand there would be some challenges regarding handling 'optional' items in cisst required interfaces (i.e. do you try to connect to a ROS topic if optional?, Do you check to see if it exists first?, Do you need a configuration file for the user to tell you what optional ones should be included?, etc.). I'm happy to participate in any brainstorming regarding how to handle these issues.

I spoke with @adeguet1 regarding this, tagging you here for your visibility.

Thanks!

[adeguet1]

I pushed a bare bone version of the code to support this feature. It is not documented nor extensively tested. It also misses code to parse a JSON file to configure the bridge (will be required for dynamic creation). To be consistent, I renamed mts_ros_crtk_bridge to mts_ros_crtk_bridge_provided which is used to bridge to a provided interface. The new class is called mts_ros_crtk_bridge_required which is used to bridge to a required interface.

To populate the bridge, I can think of 3 scenarios:

• Look at a required interface and assume everything will come from ROS. Not great for MTS_OPTIONAL features but might work for some users. This code is written but not tested yet.
• Explicitly list the commands we want to provide. The code is written and somewhat tested using a C++ method. See https://github.com/jhu-dvrk/dvrk-ros/blob/8578cbd716d014d236370b3e01c68a09efaf2e97/dvrk_arms_from_ros/components/src/dvrk_arm_from_ros.cpp#L47. I still have to add code to populate from a configuration file.
• Populate from ROS topics in a namespace. I'm not sure how convenient that is. It would also be dependent of the order nodes are started: if the cisst application is started too early the topics might not exist. I don't plan to implement this.

Use:

• jhu-dvrk/dvrk-ros@8578cbd
• jhu-saw/sawNDITracker@4cdae5c

Todo:

• Documentation
• Maybe some missing CRTK commands
• Add configuration file parsing
• Port same behavior to ROS 2 CRTK bridge

@htp2, thoughts? Usable as is?

[htp2]

@adeguet1 Just wanted to let you know I've seen this - thanks for adding this! I will test it as soon as I can (hopefully Mon or Tue).

[htp2]

Hi Anton,

I am having some trouble getting this built on my machine. I also am using sawNDITracker. I updated to the most recent devel branch there but get this error on catkin build

/home/henry/bigss/catkin_ws/src/cisst-saw/sawNDITracker/ros/mts_ros_crtk_ndi_bridge.cpp: In member function ‘void mts_ros_crtk_ndi_bridge::bridge(const string&, const string&, double, double)’:
/home/henry/bigss/catkin_ws/src/cisst-saw/sawNDITracker/ros/mts_ros_crtk_ndi_bridge.cpp:36:5: error: ‘mts_ros_crtk’ has not been declared
     mts_ros_crtk::clean_namespace(_clean_namespace);

I thought that maybe it should be mts_ros_crtk_bridge, but I get the same error. Am I missing something?

[adeguet1]

That's odd. I don't have access to the computer I used for this code so I can't test until tomorrow. Can you add #include <cisst_ros_crtk/mts_ros_crtk_bridge_provided.h> in: https://github.com/jhu-saw/sawNDITracker/blob/4cdae5c39927e8c9904442e45674366ce4eff03d/ros/mts_ros_crtk_ndi_bridge.h#L22 and see if that helps.

[adeguet1]

I think the issue is now fixed. You will need to pull the latest devel branch for cisst-ros and sawNDITracker. Can you give it a try when you have some spare time?

[htp2]

This did fix the issue - compiled without any problem! I'll keep you updated as I try to integrate this feature into our codebase

[htp2]

Hi Anton, I know it's been a while since you worked on this or we talked about it. I had an application to test it with recently and it worked quite well. I had to make one small addition for the bridge_required to connect appropriately. Additionally, for my application, I wanted to be able to bridge servo_jv so I added that functionality in as well. Both are in a pull request #17