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Miracle Blades for Mavic (Platinum)

Not being rude or trying to annoy anyone but I can't believe the number of people that don't know one of the main parts in an rc aircraft... an ESC .. Electronic Speed Controller.
Surely people should be understanding each part of a system theyre flying in the air.
Perhaps back in the days when we "enjoyed" tweaking our early Phantoms, it was useful to know subsystems like the ESCs. In fact, I recall seeing one YT video where a small fly worked itself inside the quadcopter arm and shorted out the ESC, causing what initially appeared to be a flyaway when crashing. But as systems mature, more and more subsystems are abstracted from users, gone are the days of adjusting our car's distributor "x" degrees before TDC, re-generating the CP/M operating system when adding a 8KB board, using a degausser on the magnetic head of our reel-to-reel recorders (or Phantom compass), etc.

And we can't even get "down and dirty" tweaking our beloved IMUs like the good ol' days - how dare they ;)

Then again, even with cool new tools like image transmission setting readings, I doubt many of us are aware of external microwave propagation factors to consider when making adjustments, potentially the biggest risk mitigation factor to avoid aircraft but has never been discussed by the FAA, etc. But I'll be the first to admit when I point a finger at someone else, three more are point back at me!
 
ESCs cannot be reprogrammed. The change from the former square-wave output to power the motors, to a sine-wave output to the motors requires a hardware change. This power efficiency change in the Mavic hints at things to come for P5.

ESC's cant be reprogrammed? You sure about that?
 
They are already, they have discovered by adding diamond dust/particles to the lithium they can use more pure lithium there by increasing the amount of energy it can store and still be more stable and also able to be fast charged. They found that the diamond particles stop the lithium from forming spears or sharp platelets called dendrites that short between cells that cause cell interactions and fire.
At present all lithium polymer cells only contain less than 50% lithium, rest is a polymer to hold the lithium in stability and this restricts the amount of energy the lithium can hold. By using diamond particles they can increase battery to near 100% lithium and therby double the energy and stability.
Something to look forward to in near future. Lithium diamond batterys.
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That is way too cool. Now if they can just find something less expensive than diamonds that will have the same effect!
 
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That is way too cool. Now if they can just find something less expensive than diamonds that will have the same effect!

Remember I said this earlier? lol

"Of course when they do, they'll be on sale for the low price of $199.99 per pack :eek:"
 
Remember I said this earlier? lol

"Of course when they do, they'll be on sale for the low price of $199.99 per pack :eek:"

D'oh, you *did* beat me to it. :)

As much as we lust for better batteries, we should also be glad we're not still using the Ni-Cd batteries that were the "latest and greatest" back in the '70's. We've got it pretty good, and it's still getting better.
 
ESCs cannot be reprogrammed. The change from the former square-wave output to power the motors, to a sine-wave output to the motors requires a hardware change. This power efficiency change in the Mavic hints at things to come for P5.

ESC's cant be reprogrammed? You sure about that?

Kate, I thought the same thing when I also read what John Locke said.
 
...But as systems mature, more and more subsystems are abstracted from users, gone are the days of adjusting our car's distributor "x" degrees before TDC, re-generating the CP/M operating system when adding a 8KB board,
Dude! You're like the only other person I've known that has mentioned generating a new master CP/M disk.
Gawd we're old...
 
I suspect the latest DJI update installs a new profile in the ESC's.
In any case I noticed that the MP rebooted 5 times. After each reboot a different motor "twitched" which may or may not mean a danged thing but there it is.
 
Amazon has several different manufacturers claiming to sell 8331 props...at premium prices of course.

Amazon.com: mavic 8331
 
D'oh, you *did* beat me to it. :)

As much as we lust for better batteries, we should also be glad we're not still using the Ni-Cd batteries that were the "latest and greatest" back in the '70's. We've got it pretty good, and it's still getting better.

God Ni-Cad packs are so crappy and heavy compared to modern Lithium stuff. You'd get 5 minutes of flight time! lol
Had those as a kid on RC Cars. LIPO wasn't out yet. As an adult buying a hobby grade RC Car from Traxxas and lipo 3S packs on brushless motors I was blown away. Crashed that thing a couple times and stripped out gears trying to use 3S packs on grass with a 4WD truck.
 
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1. 4dB is a tremendous improvement. 3dB is 50% reduction 4dB is 60% reduction in noise you dont think that is an improvement??
2. Agree, you need a hardware change. You can not go from squarewave PWM signal to sinewave by just changing the pulse width. The statement is totally incorrect. You are right, you need a hardware change.

You are wrong in both cases.

1. Human ear is logarithmic, 60% reduction means almost nothing on log scale.
Read here, there is a test you can check yourself
2. Sine-wave ESCs are switch-on/switch-off. Sine wave is emulated with Pulse Width Modulation. Otherwise power dissipation on the transistors will be too high. So ESC is just powerful transistors working in on- and off- mode, the moments of on- and off- is determined by firmware. In Mavic Pro these are rectangular pulses, Platinum firmware make them "smooth" by approximation of sine-wave with different "density" of rectangular pulses.
Read here
 
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You are wrong in both cases.

1. Human ear is logarithmic, 60% reduction means almost nothing on log scale.
Read here, there is a test you can check yourself
2. Sine-wave ESCs are switch-on/switch-off. Sine wave is emulated with Pulse Width Modulation. Otherwise power dissipation on the transistors will be too high. So ESC is just powerful transistors working in on- and off- mode, the moments of on- and off- is determined by firmware. In Mavic Pro these are rectangular pulses, Platinum firmware make them "smooth" by approximation of sine-wave with different "density" of rectangular pulses.
Read here
The article you reference makes the square waves look like trapezoids due to exaggerated rise and fall times.
They call these sine wave controllers because if you plot the integral over time it will resemble a sine wave - the thinner pulses result in lower voltages than the wider ones since it's on a shorter length of time. The inductive load of the motors tends to "smooth" the square waves as it opposes the positive change and as the magnetic field collapses it actually adds back to it.
In practice this helps in the sine approximation - note the lengthened "tail" of the pulse waveform. In actual operation it's likely the waves run into each other. The shape can be "tuned" by mathematical modeling of the inductive load.
As noted the drivers only dealing with on and off is more efficient operation from a power dissipation and power conservation standpoint.

rc8.gif
 
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The article you reference makes the square waves look like trapezoids due to exaggerated rise and fall times.
They call these sine wave controllers because if you plot the integral over time it will resemble a sine wave - the thinner pulses result in lower voltages than the wider ones since it's on a shorter length of time. The inductive load of the motors tends to "smooth" the square waves as it opposes the positive change and as the magnetic field collapses it actually adds back to it.
In practice this helps in the sine approximation - note the lengthened "tail" of the pulse waveform. In actual operation it's likely the waves run into each other. The shape can be "tuned" by mathematical modeling of the inductive load.
As noted the drivers only dealing with on and off is more efficient operation from a power dissipation and power conservation standpoint.

rc8.gif

$2 question...Would these Sine waves reduce noise?
I cant see how?? The only thing i can think of that can reduce noise the bell housing shape of the motors or maybe how the stator is built.
 
Well...somewhat. Think of the old way as twacking a bell with a baseball bat faster and slower.
Now use a thinner stick and hit much faster but lighter.
lol - sorry for the poor analogy but I'm in teh middle of a software synth and that's the filter on my thoughts right now...
 
$2 question...Would these Sine waves reduce noise?
I cant see how?? The only thing i can think of that can reduce noise the bell housing shape of the motors or maybe how the stator is built.
Imagine you move some heavy brick with hummer impacts and compare it with gentle push with hand. In other words, less acceleration with each current pulse produces less noise, because energy of sharp acceleration is partly goes to sound, not to the rotor movement. From spectral point of view, sharp pulses produce wide spectrum of harmonics, while for motor movement only one harmonic (rpm) is useful.
Sine wave controllers are widely used in e-bikes and noise improvement is noticeable.
 
Disclaimer: Yes I ordered the new ones

4db difference is ok but 10db difference that would be a major significance in sound reduction. But alas I am a sucker for any improvements in My Mavic. For not just the look alone.
 
According to DJIs engineer the gains are about 50% ESC and 50% propeller design. Small changes in blade design can have noticeable difference in noise. What will be interesting to see is if those noise gains equate to any losses in performance/speed. One interesting thing in DJIs description is they seem to be carefully saying that the noise reductions are at take off and landing. Either way i'll try a set of the new ones when available. I used to love testing out different blades on my 3D helis where you feel the blades and what they are doing much more than on a camera drone. Blades are like tires and can make an aircraft feel completely different in the air.
Absolutely!!! on a 3d heli blades made a huge difference for me as well, tail and main rotor. I have a feeling these will have a different feel too. I used to love trying everything and I will try these too.
 
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