Folding props

Yup, there is plenty of documentation on this elsewhere as well.
The Best Drones
"Overall, the Phantom 3 is a much better flyer than its predecessor. The new ESC motors use what DJI calls “active braking” (when you reduce throttle, the drone actively reduces motor speed instead of just cutting power and letting the props slow down); in practice this means that at full tilt the Phantom 3 can stop on a dime, which prevented us from crashing it headfirst into a window or two."

Do a web search... ;-)

RedHotPoker

yes, but this example again proves my point instead. Think about it, a quad moving forward at 50KmH, how do you stop it on a dime ? Not by slowing down, let alone stopping the propellers, but instead by providing thrust in the opposite direction. Newtons first law. What the active braking setting in the app seems to do, you can do in attitude mode with your sticks too, instead of letting the quad coast, just give full opposite control until the forward velocity is bled off. This "braking" requires extra thrust from all 4 props.

In fairness, motor braking does improve responsiveness overall, so there could be a marginal benefit even in the described scenario, the quad may be marginally quicker to transition from forward to backward pitch angle, but stopping on a dime in GPS mode is certainly not the main attraction of motor braking. Perhaps DJI chose to market this as something its not, because it would otherwise be too confusing, but as a result, its certainly confusing to me.
 
To stop it on a dime you need to do exactly what you said, force in the opposite direction of flight, otherwise active breaking by itself does not stop it on a dime.

yes, but this example again proves my point instead. Think about it, a quad moving forward at 50KmH, how do you stop it on a dime ? Not by slowing down, let alone stopping the propellers, but instead by providing thrust in the opposite direction. Newtons first law. What the active braking setting in the app seems to do, you can do in attitude mode with your sticks too, instead of letting the quad coast, just give full opposite control until the forward velocity is bled off. This "braking" requires extra thrust from all 4 props.

In fairness, motor braking does improve responsiveness overall, so there could be a marginal benefit even in the described scenario, the quad may be marginally quicker to transition from forward to backward pitch angle, but stopping on a dime in GPS mode is certainly not the main attraction of motor braking. Perhaps DJI chose to market this as something its not, because it would otherwise be too confusing, but as a result, its certainly confusing to me.




Sent from my iPad using PhantomPilots
 
I think putting on your props is the least of your worries in geting set up to fly.
I think setting up your controller with your choice of screen could be far more challenging in a difficult environment, and I haven't seen a case that fits a controller with a screen already mounted.

I'm not going to be using a case so much as padded bags within my backpack. Hopefully I'll be able to find a way to keep it all as attached as possible.
 
I know the phantom will in general work best with what it's supplied with, but the people who stuck those props in the case aren't there up the mountain with me to help me put the props on.


One quick observation - you mentioned that you probably won't have a place to set the Phantom down, and will be on a mountain side... How do you plan on launching the bird? The Phantoms NEED a flat level surface to launch and land, not to mention it needs to me level for instruments to calibrate and initiate. This is a Professional Grade precision aircraft, and not a simple TOY that can be hand launched by throwing it into the air. Plus I really wouldn't advise hand-holding it while the props are running.


As for the folding props - when I first got my P3, which was my first DJI (I _did_ have other hobby grade drones beforehand), I thought the folding props would be cool, so I ordered a set. Well, after a long battle with the overseas online seller trying to rip me off, I finally got my props. I assembled them, checked balance, and put them on my P3P. Took it outside for a test flight. Lifted off the ground about 10 ft, and it had a lot of wobble and vibration to it, but otherwise handled ok. Went up to about 65ft (to clear nearby trees) and flew out about 50ft away. Turned around to return back, but then- all of a sudden, one side seemed to drop, almost like starting a roll, and then my $1000 craft went crashing 65 feet to the parking lot below! Apparently, like another poster described, the Phantom's motor braking system probably caused a blade to fold in, therefore no longer creating lift.

I know one poster was confusing motor braking with active braking or something. Motor Braking is the system used to control flight in general. All attitudes: elevate, descend, roll and yaw, are all controlled by the motors, and how fast each is spinning.


57138b31fd6607c30cea76cc56ec76fc.jpg




Sent from my iPhone using Tapatalk
 
There seem to be plenty of cases of people happily launching and landing drones from their hands. It doesn't worry me much. The thought of setting it down on the sheet ice of a glacier just to see if slide of down a 100m crevass makes launching it from, and landing it in, my hands, preferable.

As previously asked, is there any way to disable this motor breaking? Clearly some quads, including those setup with DJI gear, happily fly with folding props. This will be used for sedate cinematic footage in the open mountains, so rapid change of direction is not much of a worry for me.
 
Your intended flying 'style' makes no difference.

Mr. Radford above gave you first-hand experience.

If you fly with anything other than DJI props you risk damage or loss... period.
It's told here over and over again.
 
  • Like
Reactions: BigAl07
One quick observation - you mentioned that you probably won't have a place to set the Phantom down, and will be on a mountain side... How do you plan on launching the bird? The Phantoms NEED a flat level surface to launch and land, not to mention it needs to me level for instruments to calibrate and initiate. This is a Professional Grade precision aircraft, and not a simple TOY that can be hand launched by throwing it into the air. Plus I really wouldn't advise hand-holding it while the props are running.
...
Sent from my iPhone using Tapatalk

Sorry but trying to launch my P3P with a 360 cam bellow fixed with a semi-rigid suspension, I had no other way to do hand launching and hand catching. There was no way to really put it on some structure, I had nothing to do that during that trip.
The point is to get the P3 almost leveled and stable for a few seconds at start so it can be initialized correctly. Then you need to go full power vertically for the launch.
 
Still watching to see if his original question gets answered. Are there any that anyone would recommend?

The answer so far seems to be a resounding NO. Folding Props are NOT recommended. But then again, it's not MY $1000 aircraft that risks failing and falling hundreds of feet to the bottom of the mountain you're on. If you'd rather risk that for just a few extra seconds of convenience, then go for it.

I'm my own experience with them, it failed after only 2 minutes in the air, and I was simply flying forward at a moderately slow speed when the prop failed.


Sent from my iPhone using Tapatalk
 
Your intended flying 'style' makes no difference.

Mr. Radford above gave you first-hand experience.

If you fly with anything other than DJI props you risk damage or loss... period.
It's told here over and over again.

Yes, and the reason is given as some sort of motor braking. I'm not saying my style will stop it crashing, I'm saying my style will not need motor braking, so surely I can turn it off and get rid of the cause of the crashes.
 
There seem to be plenty of cases of people happily launching and landing drones from their hands. It doesn't worry me much. The thought of setting it down on the sheet ice of a glacier just to see if slide of down a 100m crevass makes launching it from, and landing it in, my hands, preferable.

As previously asked, is there any way to disable this motor breaking? Clearly some quads, including those setup with DJI gear, happily fly with folding props. This will be used for sedate cinematic footage in the open mountains, so rapid change of direction is not much of a worry for me.

I do not think there is a way to disable, as it seems to be the operational design of a counter-rotational propeller system... That seems to be the basis of control for this type of aircraft, as there are no rudders, elevators, ailerons, stabilators, etc...


Sent from my iPhone using Tapatalk
 
Thanks for the suggestion. Unfortunately I also need to be carrying crampons, ice axes, food, clothing, ropes, climbing gear, a helmet. The conditions I might find myself in also require that the drone is inside something.
Seeing your list of other material, did you thought about issue of operating battery at low temperature? You will maybe need a heater for the batteries.
Sorry having no experience about folding props, good luck, seems that it will be an interesting experience you are planning.
 
I do not think there is a way to disable, as it seems to be the operational design of a counter-rotational propeller system... That seems to be the basis of control for this type of aircraft, as there are no rudders, elevators, ailerons, stabilators, etc...


Sent from my iPhone using Tapatalk

I'm slightly puzzled then. If folding props can't be used with motor braking, yet motor braking is necessary for the control of quadcopters, then why do even DJI sell folding props for quadcopters?
 
This is making me want to try the folding props to see if they really are as bad as everyone thinks. If I do, I'll definitely spend a few $'s on a balancer before I fly them.
 
As mentioned before, each motor speeds up or slows down corresponding to the control attitude applied, or computer adjustments to compensate for drift, breeze, speed, or what have you.

The "Active Braking" mentioned before as well is the method used for speed control. If you're moving in a particular direction, and change direction or thrust all together, the craft briefly applies the opposite "direction" to reduce the forward momentum. Simple physics- to come to a stop, you utilize an equal opposite action.


Sent from my iPhone using Tapatalk
 
Seeing your list of other material, did you thought about issue of operating battery at low temperature? You will maybe need a heater for the batteries.
Sorry having no experience about folding props, good luck, seems that it will be an interesting experience you are planning.

The temperature does worry me a bit, I know digital cameras I've taken up there don't last as long if I leave it sitting in my bag. Been considering various options, from having it in a chest pocket if not too big, to hand warmers in the camera bag, to maybe even sticking it in a black dry-bag on the outside to hopefully stay warm in the sun. Will have a play around when I get the chance and will be sure to make a thread about what I find works best.
 
Yes, and the reason is given as some sort of motor braking. I'm not saying my style will stop it crashing, I'm saying my style will not need motor braking, so surely I can turn it off and get rid of the cause of the crashes.

Braking, no braking, plastic or CF reinforced...Phantoms fly best with DJI props.

Please share your vids upon return.

Cheers.
 
As mentioned before, each motor speeds up or slows down corresponding to the control attitude applied, or computer adjustments to compensate for drift, breeze, speed, or what have you.

The "Active Braking" mentioned before as well is the method used for speed control. If you're moving in a particular direction, and change direction or thrust all together, the craft briefly applies the opposite "direction" to reduce the forward momentum. Simple physics- to come to a stop, you utilize an equal opposite action.


Sent from my iPhone using Tapatalk

Then how do folding props work fine on other quadcopters? If it's something that isn't necessary for flight it annoys me it can't be disabled on the phantoms.
 
Braking, no braking, plastic or CF reinforced...Phantoms fly best with DJI props.

Please share your vids upon return.

Cheers.

I'll make sure I do, along with details as to working with them in the cold etc.
 

Members online

Forum statistics

Threads
143,066
Messages
1,467,354
Members
104,933
Latest member
mactechnic