vgwit

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alternative quad motor placement
« on: June 26, 2017, 11:56:50 am »
Have a stupid question. All info I observed tell that front (and rear) pair of propellers should rotate toward each other i.e. front left propeller should rotate CW and front right CCW. Why this way and not the opposite?

My question rises from my last flight that ended with a crash in sand. There is no damage except some tiny nicks  on camera lens that resides in front of my 250 quad. I suspect that during the crash front propellers (with recommended rotation) grabbed sand particles and throwed them to lens. Similar situation happens during graceful landing in a grass - camera lens got covered with green debris.

I expect opposit rotation would throw them out of camera. What do you think?

f5soh

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Re: alternative quad motor placement
« Reply #1 on: June 26, 2017, 12:07:34 pm »
If you want to revert all motors you can simply check the "reverse all motors" in vehicle tab.
This mean you need to swap CW/CCW props and also swap the motors for correct spin direction. (assuming motors are tagged CW/CCW according to the screw used to maintain prop)

In all cases you should avoid crashes and in fact no particles around the lens :)

vgwit

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Re: alternative quad motor placement
« Reply #2 on: June 26, 2017, 12:26:41 pm »
Thanks a lot.

As I understand from your reply there no drawbacks or disadvantages of that inverted motor placement. That's all I need to know.

Mateusz

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Re: alternative quad motor placement
« Reply #3 on: June 26, 2017, 01:52:47 pm »
NASA simulated rotation https://www.nasa.gov/image-feature/ames/exploring-drone-aerodynamics-with-computers
Ok, updating post. Does not matter inwards or outwards depends on view point.
« Last Edit: June 26, 2017, 02:55:34 pm by Mateusz »

ernstock

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Re: alternative quad motor placement
« Reply #4 on: June 26, 2017, 09:45:02 pm »
Interesting question / answer
 If I may - does yaw work out ok / same. .?

Re: alternative quad motor placement
« Reply #5 on: June 27, 2017, 07:43:56 am »

ernstock

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Re: alternative quad motor placement
« Reply #6 on: June 27, 2017, 09:31:03 pm »
Thanks for link.
Excellent article.

My aching brain cell was concerned that such a reversal of all motors as discussed above would result in yaw control being reversed. ?
I suppose that even if it does reverse yaw , then this could be rectified with channel reverse either on gcs or tx. ?

f5soh

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Re: alternative quad motor placement
« Reply #7 on: June 27, 2017, 09:42:55 pm »
Quote
I suppose that even if it does reverse yaw , then this could be rectified with channel reverse either on gcs or tx. ?

The "reverse all motors" checkbox in vehicle tab handle the reverse Yaw in mixer table, not only the drawing in GUI...

ernstock

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Re: alternative quad motor placement
« Reply #8 on: June 29, 2017, 09:03:25 pm »
Ok thanks