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Dropping data at high frequency(50 -100 hz)

asked 2017-05-03 20:20:59 -0500

phivu
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updated 2017-05-04 06:36:49 -0500

Hi every body, I am collecting the data of two drones using vicon bridge. This package is only installed in unbuntu laptop. And I just subscribe the topic /vicon/..., used tf::transformstamped. And this is my major reasons why the drones' data are lost. The tf function cannot publish at the high frequency as in some reference sources. While I tested each of drones alone, the performance is alright and the data I collected is on time. The problem only happens while I run two drones at the same time. The data I collected in one file dropped a lot (occasionally 400 ms to 1 s). I tried to reduce the frequency from 100 hz to 50 hz. The dropping data is reduced but it is still not good as I expect. Any body know how to deal with this problem? Thanks Many thanks,

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answered 2017-05-04 05:46:43 -0500

Stefan Kohlbrecher

24361 ●173 ●299 ●444 https://www.energy-rob...

The quality of a wireless connection (bandwidth, latency, availability) can vary widely due to many factors such as load, other devices in the environment, motion of platforms, shape of the environment etc. There is no silver bullet to fix your problem, some straightforward things to try are:

Optimize aforementioned factors (less distance, less interference..)
Record data onboard the drones
Reduce amount of data transmitted (for instance close rviz, which per default subscribes to tf)
Get better WiFi hardware

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I agree. We using velodyne over a wireless network. When we use a 300M mini router, we only get a publish frequency of 2Hz. Now we are using a dual-band router, we can almost get the original 10Hz data.

Tixiao ( 2017-05-04 07:23:52 -0500 )edit

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Asked: 2017-05-03 20:20:59 -0500

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Last updated: May 04 '17

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