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High latency images messages

asked 2019-04-30 10:25:56 -0500

Rosbq gravatar image

Hello everyone,

I have a system composed of a robot (android machine using rosjava) and a computer (roscore), both correctly synchronized. The robot publishes rgb-d images over WiFi. The computer subscribes to these images in order to process them and carry out slam and navigation. The robot is also subscribed to these topics, in order to check if the images are correctly sent. My problem is that if the publishing rate in android is set to a value above 1 or 2 FPS, the latency between both systems start increasing. When I check the latency in the images messages in the master machine (using echo --offset), it starts growing quickly, starting at -1 sec, and finally obtaining values of -220 secs. However, if I check the messages received in the android machine, these are correctly received. Both machines are correctly synchronized. If the messages are publishes at a rate=1FPS, the latency is -1 sec approximately. When I start the SLAM node and the navigation module, sometimes this latency also starts growing, producing problems with the algorithms.

The problem is that in order to carry out SLAM and navigation modules, I need a higher frequency.

Anyone knows what causes this problem and a possible solution? Thank you very much in advanced.

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answered 2019-05-02 07:48:51 -0500

Rosbq gravatar image

updated 2019-05-02 07:52:06 -0500

Finally I was able to solve the problem creating a wired connection between the PC and the router. Now everything works!

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Asked: 2019-04-30 10:25:56 -0500

Seen: 344 times

Last updated: May 02 '19