How to rewrite the examples to get the position of the crazy

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Jun-ichi Toji
Beginner
Posts: 4
Joined: Wed Jul 01, 2020 6:24 am

How to rewrite the examples to get the position of the crazy

Post by Jun-ichi Toji » Thu Jul 16, 2020 12:51 am

I have a question about rewriting the program to get the position of the crazyflie.

I browsed this post
viewtopic.php?t=2867.
I understood that parameters in any example python file need rewriting to stateEstimate.x, stateEstimate.y and stateEstimate.z, but I don’t know which part on files.
The variables list of logTOC tab in the client includes stateEstimate.x, stateEstimate.y and stateEstimate.z.
I’m a program beginner, so I would like to know in detail.

Thank you.



kimberly
Bitcraze
Posts: 456
Joined: Fri Jul 06, 2018 11:13 am

Re: How to rewrite the examples to get the position of the crazy

Post by kimberly » Thu Jul 16, 2020 8:32 am

Hi!

So you need to look at the examples folder of this repository. Make sure that the you follow the readme to install cflib or have done

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pip3 install cflib
You can use both the basiclog.py or basiclogSync.py (the last one is easier to understand I think). Make sure that you try out one of these to check if you can connect to your crazyflie (if you haven't changed your uri yet:

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python3 examples/basiclog.py
In both files you have the following lines:

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        self._lg_stab = LogConfig(name='Stabilizer', period_in_ms=10)
        self._lg_stab.add_variable('stabilizer.roll', 'float')
        self._lg_stab.add_variable('stabilizer.pitch', 'float')
        self._lg_stab.add_variable('stabilizer.yaw', 'float')
You simply change those to:

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        self._lg_stab = LogConfig(name='Position', period_in_ms=10)
        self._lg_stab.add_variable('stateEstimate.x', 'float')
        self._lg_stab.add_variable('stateEstimate.y', 'float')
        self._lg_stab.add_variable('stateEstimate.z', 'float')
hope this is clear enough to get you started!

Jun-ichi Toji
Beginner
Posts: 4
Joined: Wed Jul 01, 2020 6:24 am

Re: How to rewrite the examples to get the position of the crazy

Post by Jun-ichi Toji » Thu Jul 23, 2020 12:35 pm

Thank you for your kind reply.
Thanks to you, we can now see the positions of crazie.

I have additional quastion.
I want to get the flight position at the same time when performing flight control using initial_position.py, but I don't know how to rewrite it.

Could you give me some insight into this?

kimberly
Bitcraze
Posts: 456
Joined: Fri Jul 06, 2018 11:13 am

Re: How to rewrite the examples to get the position of the crazy

Post by kimberly » Fri Jul 24, 2020 7:46 am

You can setup a callback function for your logging variable in that case.

By the way, I would highly suggest you to try out this new tutorial: https://www.bitcraze.io/documentation/r ... log_param/. It is brand new and still tested, so therefore not in the tutorial list yet, but teaches you how to work with the parameters and logging framework, so afterwards you will be able to implement this in your own code.

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