ROS GPS node - trying to get gpsd_client to work (accept suggestions)

Question

Hey there,

I have been trying to get a ROS node to work with my GPS (Garmin GPS18x-5hz).

I found the gpsd_client and although I'm using indigo and not hydro, I installed it anyway and tried to run it. I was following the tutorial on their page but I'm unable to get the GPS data on the topic /fix. When I try to echo the topic I don't get anything, and when I try to use gpscat to check what's coming from the GPS port I get some not human readable data, that is, it's not in the NMEA protocol.

On the other hand when I run the gpsd daemon and telnet the port selected, I have to send the command: ?WATCH={"enable":true,"nmea":true} in order to start receiving data in the nmea protocol.

Can you help me out? I'm rather new to the ROS environment and never used a GPS before.

EDIT: The type of data I receive when I use gpscat is the following:

$ gpscat -s 19200 /dev/ttyUSB0

P!\xb6f\xae>\x1aF\xe64\xdf\x10!\x96 ~\x18zH \xe0HR.ck\xfc*\x08&N\xce\x07\x88\x8c-\xcaO\xa04 X6\x1a^\x08\xa8\xc8\x0er\x13 \xffP!\xb6f\xee>\x1a\x06\xe64\xdf\x10!\x96L~\x18zH\x8c\xe0\x08R.ck\xfc*\x08&N\xce\x07\x88\x8c-\xcaO\xa04 X6\x1a\x1e\x08\xa8\xc8N2\x11 \xffP!\xb4f\xee>\x1aF\xe64\xdf\x10!\x94 ~\x18:H \xe4\x08R\xbeck\xfc*\x08&\x0e\xce'\x08\x8c-\xcaO\xa04 X6\x9a^\x08(\xc8\x0e2\x10 \xffP!\xb4f\xae>\x1aF\xe6t\xdf\x10!\x94 ~\x18\x1aH\x8c\xe4HR.ck\xfc*\x08&\x0e\xce\x07\x08\x8c-\xcaO\xa0e X6\x1a\x1e\x08(\xc8\x0e2\x10 \xffP!\xb4fn>\x1a\x06\xe64\xef\x10!\x94L~\x18\x1aH\x8c\xe4\x08R.ck\xfc*\x08&N\xce\x07\x88\x8c-\xcaO\xa04 X6\x1a\x1e\x08(\xc8\x0e2\x10 \xffP!\xb6f\xee>\x1aF\xe64\xef\x10!\x96 ~\x18:H \xe4\x08R.ck\xfc*\x08&N\xce\x07\x88\x8c-\xcaO\xa04 X6\x1a\x1e\x08(\xc8\x0e2\x11 \xffP!\xb6f\xae>\x1aF\xe6\xf4\xef\x10!\x96 ~\x18:H \xe4\x08R.ck\xfc*\x08&N\xce\x07\x88\x8c-\xcaO\xa04 X6\x1a\x1e\x08(\xc8\x0e2\x10 \xffP!\xb4fn>\x1a\x06\xe64\xdf\x10!\x94\x8c~\x18:H\x8c\xe4\x08R.ck\xfc*\x08&N\xce\x07\x88\x8c-\xcaO\xa04 X6\x1a\x1e\x08(\xc8N2\x11 \xffP!\xb4f\xae>\x1aF\xe6\xf4\xcf\x10!\x94

(Not exactly like this it has spaces between messages)

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Originally posted by nvoltex on ROS Answers with karma: 131 on 2014-12-15

Post score: 0

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Original comments

Comment by Tom Moore on 2014-12-16:
Have you tried different baud rates in gpscat? If not, try 9600, 38400, etc. Also, if you have a Windows installation somewhere, have you tried downloading its official software to see if the unit is functioning correctly?

Comment by nvoltex on 2014-12-16:
From the documentation this is the correct baud rate. In fact, through the gpsd I was able to retrieve data from the GPS with the nmea protocol. But, although it was supposed to be the protocol used by default, I don't get it if I simply try to gpscat the port to which the gps is connected.

Answer 1

I've had better luck with nmea_navsat_driver: http://wiki.ros.org/nmea_navsat_driver. Give that a shot and see if you get better results.

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Originally posted by Tom Moore with karma: 13689 on 2014-12-15

This answer was NOT ACCEPTED on the original site

Post score: 1

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Original comments

Comment by nvoltex on 2014-12-16:
In fact I already tried the nmea_navsat_driver, however I get the same problem, that is, no messages on the topic. EDIT: After testing again it seems to receive the data from the GPS (although the topics are blank), the problem is that it is receiving the information in that strange format.

Answer 2

I ended up being able to get the GPS coordinates with the gpsd_client package. And if I'm outdoors the topic /fix actually outputs the correct GPS coordinates. However this means that I always need to use gpsd in order to work with the gps. I was unable to get the nmea_navsat_driver to work.

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Originally posted by nvoltex with karma: 131 on 2014-12-16

This answer was ACCEPTED on the original site

Post score: 0