Localisation technology

[LukasJames]

Hello everyone, just ordered a CF and waiting for it to be delivered.. In the meantime I thought I would join and start reading up.

I'm very interested in autonomous flight and found the following video during my research:
http://www.ted.com/talks/raffaello_d_an ... e#t-471092

I would be keen to hear your thoughts on the localisation technology that he mentions in relation to the swarming effect produced and how these might be being controlled. He says that each unit knows where it is in space and is self controlled there is no limit to the number in the swarm.

Luke

[chad]

I'm not sure if you have seen the following Bitcraze blog posts, but the team is busy creating a local positioning system that will help the Crazyflie know where it is in space.

Crazyflie autonomous with DWM1000-based local positioning system
Local positioning system alpha program launch
Producing the Alpha LPS DWM1000 boards

Also, Wolfgang Hoenig, a community member here has been working academically with swarms using the Crazyflie.

Maybe these are good candidates for your further reading?

[whoenig]

For the video they used a VICON motion capture system I believe (http://vicon.com/). Those systems are *very* expensive, however you can find them at universities which specialize in those kinds of things. With an optical motion capture, you can achieve sub-mm accuracy at >100 Hz update rate.

The new bitcraze localization system will be much more affordable, but less accurate. However, it hopefully will be sufficient for non-aggressive maneuvers.

Those techniques don't scale too well: the largest swarm I've seen flying was 20 quadcopters using VICON (not Crazyflies though).

Wolfgang

[LukasJames]

Thanks for your responses.

Chad, thanks for the links you sent, I have taken a look and I'm interested to see how the DWM1000 boards progress and how scaleable they can be.

Wolfgang, regarding the localisation tech, I am not sure they are using a motion capture system, at the beginning of the talk he explains that they are using a new localisation technology developed by Verity Studios and that no external cameras are used in the demos. I have taken a look on the Vicon website and looks like they have some interesting products though.

He also mentions that each device is able to know where it is in space and can work autonomously meaning there is no limit to the number of devices that would be able to be part of the swarm.

If there is some type of sensors embedded on the device, its difficult to see anything in the video, I have taken a still and attached this to see if you guys can spot anything?

Thanks again for your input!

Luke

Edit:
I found some more info on the research these guys have been doing which could give some clues as to which technology they are using:
http://flyingmachinearena.org/research/
http://ieeexplore.ieee.org/xpl/articleD ... er=7353810

[derf]

Hi,

Two of the publications contain references to "Ultra-wideband ranging radios", which sounds very similar to what Bitcraze is developing with the LPS.

Anton Ledergerber, Michael Hamer, and Raffaello D’Andrea, “A Robot Self-Localization System Using One-Way Ultra-Wideband Communication”, IEEE/RSJ International Conference on Intelligent Robots and Systems, 2015.
DOI

Mark W. Mueller, Michael Hamer, Raffaello D’Andrea, “Fusing ultra-wideband range measurements with accelerometers and rate gyroscopes for quadrocopter state estimation”, IEEE International Conference on Robotics and Automation, 2015.
DOI

To bad the publications cost money (33$!! for a PDF).

Maybe the Bitcraze team can ask the ETH Zürich researchers for some insights.

Regards,

Fred

[arnaud]

This is very interesting!

They seems to be using the same radio module as we are, the DWM1000. If so, it is really nice to see what the module and the UWB system is capable of.

I got the papers, now let see what can be implemented (these things tend to be full of math ... ).