Quadcopter is not lifting off high enough

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sunnyB
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Joined: Wed Apr 22, 2015 4:44 am

Quadcopter is not lifting off high enough

Post by sunnyB »

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Last edited by sunnyB on Sat May 02, 2015 3:07 pm, edited 1 time in total.

FengShuiDrone
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Location: ......

Re: Quadcopter is not lifting off high enough

Post by FengShuiDrone »

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Last edited by FengShuiDrone on Fri Aug 07, 2015 11:45 pm, edited 1 time in total.

sunnyB
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Joined: Wed Apr 22, 2015 4:44 am

Re: Quadcopter is not lifting off high enough

Post by sunnyB »

There is a failsafe on there that i have tested.
Loss of Radio will tell make all inputs go to Zero to avoid crash.

My LiPo battery was fully charged during that video.
Perhaps i should get 30c batteries?

FengShuiDrone
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Re: Quadcopter is not lifting off high enough

Post by FengShuiDrone »

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Last edited by FengShuiDrone on Fri Aug 07, 2015 11:46 pm, edited 1 time in total.

Cereal_Killer
Posts: 221
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Re: Quadcopter is not lifting off high enough

Post by Cereal_Killer »

Can you post some more details on your "radio"? Is it PPM SUM or a standard receiver? What radio is it actually using (just guessing an NRF24L01+)? Why did you want to do it like that, just to save money? You can get an orange Tx or a Devo 7E for around $65 and a <$10 DSMX rx and be WAY BETTER off as far as range and safety and features. Can you take a video showing the RC input's on the GUI so we can see they're all normal?


There isnt enough data here to make any real observations but I too an leery of the 20C battery. Is it atleast new? Do you have a more powerful cell you can test with (or a second one of those you can parallel in for testing)? That one there, in perfect condition, is only capable of about 40A and that's probably just not enough power for a 525 size quad. What's your AUW?

QuadBow
Posts: 532
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Re: Quadcopter is not lifting off high enough

Post by QuadBow »

What about your ESCs?
Have you checked the overall performance via http://ecalc.ch/xcoptercalc.php?ecalc&lang=en?

FengShuiDrone
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Re: Quadcopter is not lifting off high enough

Post by FengShuiDrone »

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Last edited by FengShuiDrone on Fri Aug 07, 2015 11:48 pm, edited 1 time in total.

sunnyB
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Re: Quadcopter is not lifting off high enough

Post by sunnyB »

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Last edited by sunnyB on Sat May 02, 2015 3:08 pm, edited 1 time in total.

Cereal_Killer
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Re: Quadcopter is not lifting off high enough

Post by Cereal_Killer »

I'd still advice, especially with current public opinion of "drones" that you use a real, proven radio system, if for nothing more than liability concerns... Are you at least using PA'd NRF modules on both the "tx" and the quad?

Back to your problem, I do think the input's look ok (tho the closer to 1500 dead even you can get the better, but anyway) I think I would be suspicious of your battery first. Have you used a calculator to figure out your power consumption? I bet it'd tell you the 42A your cell can do isnt enough power.

Have you balanced the props? Do the motors sound like they / the props are balanced well when spun up?


Edit:
What's your AUW? Also have you actually measured the props to ensure they're 10 inchers? I went back to your first video and, tho you never see them not spinning they look tiny to me against the frame / your body.

FengShuiDrone
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Re: Quadcopter is not lifting off high enough

Post by FengShuiDrone »

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Last edited by FengShuiDrone on Fri Aug 07, 2015 11:48 pm, edited 1 time in total.

sunnyB
Posts: 5
Joined: Wed Apr 22, 2015 4:44 am

Re: Quadcopter is not lifting off high enough

Post by sunnyB »

Yes im using the nrf240l01 pa'd versions.
During testing, i have experienced no packet transmission loss (atleast within 50 ft because that is what i have tested multiple times). Currently, i do not plan sending my quadcopter out very far from me right now. Just trying to do something that has been relatively cheap (under $110 for everything so far since i have receive parts from friends and such other than the motor and esc's.)


i have not balanced my props but the motors sound relatively normal (after comparing it to other youtube video audio). They aren't all whacky or anything.

I do not know my AUW (noob? Yes i am a noob). But i will do that soon.

I have not measured my props (will do that soon too and reply with update) but it says online that the 1045 propellors are 10 inches.


Ya i have noticed my motors are not spinning as fast as they should because they are freakin' 1000 kv but they are spinning as if they were 100 kv (overexaggeration). Without calculating anything else, i am positve at this point the battery is not sufficient because the motors are not screaming like they should be. Do you guys agree?


And yes, it is that easy adjust the max throttle (unless you were being sarcastic, then i understand). I have it set to 2000. I have also had it at 1850 and 1900 before.


How would i adjust the throttle curve? In the MultiWii GUI?

FengShuiDrone
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Re: Quadcopter is not lifting off high enough

Post by FengShuiDrone »

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Last edited by FengShuiDrone on Fri Aug 07, 2015 11:47 pm, edited 1 time in total.

Cereal_Killer
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Re: Quadcopter is not lifting off high enough

Post by Cereal_Killer »

sunnyB wrote:I do not know my AUW (noob? Yes i am a noob). But i will do that soon...
...I have not measured my props (will do that soon too and reply with update) but it says online that the 1045 propellors are 10 inches...


I think before we try any more random guessing I'll wait till you get back to all of the questions so far before contemplating more but to clear a few things up for you...

AUW = All Up Weight, the total weight at take off (including all equipment / the battery)

If you dont know your AUW it's pretty clear you have not used a prop / motor / battery calculator (not to be hard on you, its understandable, especially with you young guys. Why do the hard stuff and run the numbers when you can just buy parts someone else told you about and try first, I get it, been there, done that lol...) since AUW is like the number one thing you have to put in to those to get the best solution out. Even tho you've already bought the parts and built it I'd recommend you go back and plug all the numbers into a calculator (ecalc is good but it costs $0.99 to use [tho that's a single fee for life] and it pretty accurate). I'd run the numbers man, even if you dont understand or care, it's still very useful data to have and will help you learn in general, plus once you know how to do it you'll be able to come up with your own parts combo's, not just ask your buddies for spare parts that'll work together for your next one.


Then about the props, yes a 1045 is a 10" prop, that's why I asked if you measured, cause like I mention they look small compared to the quad (and also your feet in the video). I was thinking maybe the kit could have accidentally been shipped with 8" props, that would definitely keep you on the ground with those motors / that battery (8" props could fly that size quad but you'd need higher kV motors and you'd really have to try and cut weight everywhere possible).

BTW the first number is the size, the second number is the pitch so for e.g. a 1045 is 10" long and [in a theoretical perfect fluid with zero losses] it will move forward 4.5" for every full rotation (but again DO NOT expect this in real life, in air fighting turbulence and gravity, that's just a way to spec them)



One final thought (just giving you a hard time about your radio still). You may not think so now but I promise you, once it's up and running well and you've got some stick time you will VERY QUICKLY outgrow that radio. 100' (even 100 yards) is NOTHING, especially with a 550, heck I fly my 120 size (that's tiny) mini-tricopter 100' out and on my 250-300 size modes I use the full range! BTW "full range" on DSMX equipment is 2km and it quickly becomes not enough, especially with trees and terrain and wifi networks screwing the signal up. I'll drop it after this but dude, you've have to get something better eventually! I imagine this it true with a lot of us- my Tx is the SINGLE MOST EXPENSIVE piece of equipment I own for the hobby! The completed quad costs more sure, but the single most expensive piece of equipment on said quad doesnt come to 1/4 the cost of my Tx, that's just how it is, you gotta pay to play.
I highly advise you check out the devo line of open source transmitters, join up at DeviationTX.com and show off your current setup. I'm sure it's cool, and it obviously works, it's just not really appropriate for the size MR you're flying, an indoor toy sure, but like mentioned if something happens with that thing you've got and it goes down into someone / something it's gonna do serious damage. I'm an electrical engineer by trade and with all the stuff I've worked with before EVEN STILL I wouldnt trust something I built from an arduino to fly a 500+ gram aircraft with 4 10" super fast SPINNING BLADES above people's head's with a questionable radio link. But again I get it, you're young, you've probably never been sued before...

my $0.02
/subject dropped tho, I'll stick around to try and get you flying.


Man to be young again...

sunnyB
Posts: 5
Joined: Wed Apr 22, 2015 4:44 am

Re: Quadcopter is not lifting off high enough

Post by sunnyB »

Do you know why the motors are spinning as fast as they should be though? I have parked my quadcopter for the time being until i i get a proper radio transmitter and receiver.
But i am afraid i will get the same problem as i am now, which is that the motors do not spin as fast they should.

When i am testing the motors at my desk (i do remove all props and such) and when i run full throttle, the motors spin quite fast with the 20C (i can hear the motors scream!)
But once the propellors are on, it seems they are spinning at around 60% or maybe even less throttle (because the motors seem really shy and not loud). Any possible conclusions on why that happens?

waltr
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Location: Near Philadelphia, Pennsyvania, USA

Re: Quadcopter is not lifting off high enough

Post by waltr »

Do what Cereal_Killer suggested, use a Copter calculator (Ecalc) and plug in all the parts and numbers.
Until you do all of us are out of this discussion and you are on your own.

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