ROS Interfacing Issue

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gebotics
Posts: 4
Joined: Mon Nov 26, 2018 10:32 pm

ROS Interfacing Issue

Postby gebotics » Mon Nov 26, 2018 10:43 pm

I'm trying to integrate the Marvelminds with ROS on a Linux machine, but nothing happens.

I start the roscore, then follow the instructions found at: https://marvelmind.com/pics/marvelmind_ ... 09_11a.pdf.

I use the rosrun marvelmind_nav hedge_rcv_bin command (my port is /dev/ttyACM0) and it says that it opened the serial port with baudrate 9600, but then nothing else prints to the screen. I also tried to run the subscriber test and it starts, but nothing prints to the screen. It appears that ROS isn't receiving any data from the hedgehog, but I can't figure out why.

My map is setup with the modem running on a Windows computer, and my hedgehog is setup on that computer, and is plugged into the Linux computer.

Any help would be greatly appreciated.

smoker77
Posts: 230
Joined: Sat Feb 06, 2016 4:03 pm

Re: ROS Interfacing Issue

Postby smoker77 » Sun Dec 02, 2018 8:13 pm

Hello,

You should freeze the submap to get coordinates data from hedgehog.
Please check the submap is frozen and hedgehog updates its position in dashboard.
If this will not help, please share screenshot of dashboard and file of settings generated after pressing 'save map' button on bottom part of dashboard.

gebotics
Posts: 4
Joined: Mon Nov 26, 2018 10:32 pm

Re: ROS Interfacing Issue

Postby gebotics » Mon Dec 03, 2018 7:38 pm

The submap was frozen and the hedgehog updates it's position in the dashboard just fine, but it won't print out to ROS.
I attached the screenshot of my dashboard, but it tells me the map I saved has the wrong file extension (.ini) and won't attach it.
Attachments
dashboard_2018_12_03_000.png

gebotics
Posts: 4
Joined: Mon Nov 26, 2018 10:32 pm

Re: ROS Interfacing Issue

Postby gebotics » Mon Dec 03, 2018 8:05 pm

I put the map information into a github gist, try the link below for that information.

https://gist.github.com/mollystieber/6e ... 7ef84f137b

smoker77
Posts: 230
Joined: Sat Feb 06, 2016 4:03 pm

Re: ROS Interfacing Issue

Postby smoker77 » Sun Dec 09, 2018 8:41 pm

Hello,
It seems your tracking is not very good. I see 2.1 Hz update rate on the bottom of the screenshot, but the setting is 16 Hz. Normal update rate should be at least 8 Hz for your map. Try to remove unused submap 1. Also try to rebuild the map - unfreeze submap 0 and freeze it again after several seconds.
We just tested and ROS reading is working in our case.
For testing you can also try to get data via C example in Windows or Linux without using ROS:
http://www.marvelmind.com/pics/2018_03_15_C_example.zip


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