Mavic Pro Motor Mod

[chazz]

You wanted airflow Lolo, here's your airflow

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Nice dude! i think you're the engineer!

 

[beanbubba]

Well I think Sir Lolo is right again. I do believe the additional fan has made this mod real and repeatable.

I am not an expert on the csviewer output, but this looks pretty darn good to me. Feedback is welcome on the data.

This flight was just under 45 minutes with a 7800mAh/4s+4000mAh/4s and 1750 grams.

EDIT: I suspected I fried something from previous tests, so I built a brand new mavic (#11) with all new parts for this mod to rule out any other potential unknown issues.

 

[lolo780]

Graphs look great, especially the ESC temps. Is it nose heavy?
Could you show total motor power? From roughly calculating it seems like around 6.5g/W?

 

[beanbubba]

Graphs look great, especially the ESC temps. Is it nose heavy?
Could you show total motor power? From roughly calculating it seems like around 6.5g/W?

Remember I am a csviewer noob. I don't see anything labeled total motor power, can you throw a dog a bone here??

 

[lolo780]

Remember I am a csviewer noob. I don't see anything labeled total motor power, can you throw a dog a bone here??

Motor watts avg total I think.

 

[beanbubba]

Motor watts avg total I think.

This is the closet chart I could find with that description:

 

[beanbubba]

Maybe this one??

 

[beanbubba]

Graphs look great, especially the ESC temps. Is it nose heavy?
Could you show total motor power? From roughly calculating it seems like around 6.5g/W?

Yes it is nose heavy. Need to figure out a new attachment method.

 

[beanbubba]

Here is Mavic11 in all her newly minted glory!

I am thinking this mod might actually work... knock on wood

 

[lolo780]

Looks like 240W to hover 1750g. 7.3g/W.

 

[beanbubba]

BTW - the second knock off battery controller is the one to get (the LEDs are triangles instead of circles and there are stripes along the topside). This one has no special startup procedure like all the others. If you are going to do this battery controller mod get this one and not any of the others.

1) connect battery case to the bird.
2) connect the balance cable to your battery.
3) connect the battery power to the birds external power connector.
4) DONE (controller auto powers on).

All the other controllers have convoluted startup procedures, this one rocks.

 

[beanbubba]

Looks like 240W to hover 1750g. 7.3g/W.

Please speak English

I do not know what to compare this against.

 

[beanbubba]

@BudWalker i am new to your software this week and all I can say is a giant thank you for contributing this to the community. It is evident that you put a lot of time and effort producing this product and it is awesome. Thanks again.

 

[beanbubba]

This is the real test and next on my docket today.

 

[beanbubba]

I have tweaked the rotor arm design many times. This is the final version that is perfect.

In the beginning I hesitated to make the arms too strong (to save weight). But with 2 kilos strapped to the bird, I don't think anything less would hold up.

If you do try this mod, discard all the previous 3d print files and use this one:

 

[beanbubba]

If you want to try the battery controller + fan mod, here is the 3d print file:

 

[beanbubba]

I think we might have a winner. Numbers went up as to be expected, but last time I did this same weight test without the second fan, crashed and burned around 10 minutes.

I limited this flight to 10 minutes to get the following data readings. AUW was 2.1 kilos.

EDIT: all four motors were noticeably hotter, but I could touch and hold them still.

 

[beanbubba]

I think we might have a winner. Numbers went up as to be expected, but last time I did this same weight test without the second fan, crashed and burned around 10 minutes.

I limited this flight to 10 minutes to get the following data readings. AUW was 2.1 kilos.

EDIT: all four motors were noticeably hotter, but I could touch and hold them still.

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I estimate 310w avg to hover and that’s 6.8g per w. I still don’t know what to compare this against. Do you have any examples of good versus bad??

 

[lolo780]

I estimate 310w avg to hover and that’s 6.8g per w. I still don’t know what to compare this against. Do you have any examples of good versus bad??

If you compare watt hours of battery capacity to g/W, at a certain point you'll be at the top of the flight time curve where adding more battery past that will lose flight time due to reduced power system efficiency.

If your hover wattage is up 30%, how many % did you add in battery capacity.

Also worth noting that as you reduce the C draw on your batteries the effective useable power goes up.

 

[chazz]

I think we might have a winner. Numbers went up as to be expected, but last time I did this same weight test without the second fan, crashed and burned around 10 minutes.

I limited this flight to 10 minutes to get the following data readings. AUW was 2.1 kilos.

EDIT: all four motors were noticeably hotter, but I could touch and hold them still.

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Can have a copy of that data file?