So i've seen loads of these on site so am not even sure i'll get answered but here goes for the hope -
I'm about to upgrade from a coupe of DJI quads to building my first own Hex. It is for professional video and will carry a Canon 7D DSLR.
I am looking at the Tarot MAX6 umbrella folding six-axis aircraft / 16mm LY685.
Before I launch into finding out what motors or ESC's and all that mean and what ones to use i would like to start with the right frame.
Any other advice would be greatly appreciated and direction to go from here would rock.
Replies
So I am looking at Helipal or HobbyKing.
These are the 2 so far. I know one is still the Tarot X6 :(
Tarot X6 Hexacopter Set
- Camera Gimbal No, I don't need it
- ESC 6 X Hobbywing XRotor 40A-OPTO ESC
- Flight Controller 1 X DJI NAZA V2 Flight Controller
- FPV Monitor Mount No, I don't need it
- FPV Package No, I don't need it
- iOSD Mini No, I don't need it
- Motor 6 X Tarot 5008 340kv High Power Brushless Motors
- Propeller Mount 3 X Storm Self-Tightening Propeller Mount (CW + CCW / pack)
- Propellers 3 X Tarot 1855 Carbon Fiber Propellers (CW + CCW / pack)
- RC Controller No, I don't need it
DJI S900
Specifications :Frame
Motor
ESC
Foldable Propeller (1552/1552R)
Flight Parameters
Gain Settings
It should also be noted that given the forum you are on, the Pixhawk is superior to the DJI offerings when comparing flight controllers. ;-)
Again, I am not a expert in heavy lift but both of those options appear to be sufficient for what you want to do.
I would expect better flight time from the Tarot given the larger propeller diameters, but the only way to be certain is with physical testing. DJI indicates that at 6.8Kg it will hover at 1000W, while ecalc.ch indicates the Tarot will hover at 900W (at the same weight), which should indicate ~10% better flight time given the same flight weight.
DJI's numbers above seem slightly inconsistent. They state it will hover at 1000W for 18min (@6.8Kg), but if you do the math that indicates a total battery usage of 13500mAh if you assume average 22.2v (starts at 25.3v and drops to 19.2v - average 22.2v). Either it hovers at less than 1000W or DJI is not accurate about the battery capacity they used for their test. I might also be missing some other detail to explain the discrepancy (non-linearity of voltage drop?).
I like the motor mounting, integrated motor cooling, and angled and twisted mounts on the DJI. The Tarot design seems reasonable, but again this is not my specialty so I don't know if there are "must have" features either one is missing.
As I mentioned in your PM, I am not an expert with heavy lift copters, so use my advise with caution.
A 7D DSLR with lense is heavy... really heavy. The gimbal needed to carry a camera that large is heavy as well. Using back-of-the-envelope numbers the weight for your non-drive components will come out to ~4Kg (camera, gimbal, frame, controllers, transmitters, receivers, and other misc.) The weight of typical drive components (batteries, ESC, motors and propellers) to carry a load this large may be roughly another 4Kg. This brings your flight weight to ~8Kg. These are broad generalizations and will vary, but I believe they're reasonable initial estimates.
With the frame you are looking at the max propeller size you can use is about 330mm (13"). This is really small for the amount of weight you need to carry. I would recommend you look for a frame capable of using 20" propellors (or even larger). As a generalization, larger props will give you more flight time for the same amount of battery usage (assuming the correct motor is used).
That is really good advice, thanks man. So if I go with the DJI S900 Spreading wings I sould get up to a 15" or slightly bigger prop.
What do you think about the rest of the specs on a stock s900?