Why hasnt Japan or the USA produced a competitive drone?

[Former Member]

And really why would they? If you have a golden goose willing to buy everything you can make and more with 30 year contracts paid before the product is even on the assembly line why would you do anything else? Sounds like a good gig to me

Sad but true. Hey but think of things like night vision goggles, Hummer H-1's, and other military and similar items that were watered down for civilian use.

 

[Kilrah]

What feature would be so great that you would be willing to try out an untested company’s product? Idk to tell you the truth. DJI has eared a lot of trust points with me

That's indeed a problem. I believe the tech for this kind of product has reached a plateau, and there isn't really any more to add to it to give a competitive advantage to anyone wanting to enter the market. All they could do is either offer it cheaper (good luck) or do minor improvements that won't have much convincing power.

 

[WithTheBirds]

That's a good catch. I believe the tech for this kind of product has reached a plateau, and there isn't really any more to add to it to give a competitive advantage to anyone wanting to enter the market. All they could do is either offer it cheaper (good luck) or do minor improvements that won't have much convincing power.

This observation would seem to be evidenced by DJI's own statements about future directions. Make their consumer products smaller and focus on tailoring models to meet the demands of specific industry use cases. The technology enabling obstacle avoidance/computer vision, power train efficiency, battery capacity etc are all bought in and presumably available to competitors.

No doubt a few entities would be able to match or better DJI in the manufacturing component. Being first to market with a great product has a lot going for it though it seems.

 

[AnzacJack]

I agree. Really only thing to improve is endurance, cameras and weight for this class of drone, and DJI has squeezed as much as available.
I remember having to update my computer almost yearly, to be able to run latest software. These days my rig is prob 3 years old and still running all the latest software

 

[brett8883]

I think somebody is gonna have to find a higher energy dense power source or somehow find a way to recycle some energy(I’m thinking Tesla regenerative braking) to get the flight time up substantially and then tick all the same boxes as DJI at approximately the same price point to really get me to think about switching. Pretty tall order

 

[WithTheBirds]

I think somebody is gonna have to find a higher energy dense power source or somehow find a way to recycle some energy(I’m thinking Tesla regenerative braking) to get the flight time up substantially and then tick all the same boxes as DJI at approximately the same price point to really get me to think about switching. Pretty tall order

DJI already employs regenerative braking switching the motors to generator mode to rapidly decelerate them- at least that is one of the claimed benefits or what they call "active braking".

Higher power density solutions currently exist- problem is cost. You probably wouldn't be comfortable paying the premium until price and reliability/convenience issues are resolved.

 

[Former Member]

All they could do is either offer it cheaper (good luck) or do minor improvements that won't have much convincing power.

Do you mean... someone would do a knockoff of DJI? A knockoff of a Chinese company? Interesting.

 

[brett8883]

DJI already employs regenerative braking switching the motors to generator mode to rapidly decelerate them- at least that is one of the claimed benefits or what they call "active braking".

Higher power density solutions currently exist- problem is cost. You probably wouldn't be comfortable paying the premium until price and reliability/convenience issues are resolved.

Active braking just means it doesn’t have to rapidly tilt the other way to brake. I was just using it as an example but in a Tesla (probably other electric cars too but it’s the only one so I know anything about) when you pull your foot off the accelerator the car doesn’t coast it actually resists the forward momentum and the rotational energy is converted back into electricity, like a turbine, and recharges the battery with that energy which otherwise is lost due to applying the brake. Tesla’s almost don’t need brakes. Almost

 

[Kilrah]

I remember having to update my computer almost yearly, to be able to run latest software. These days my rig is prob 3 years old and still running all the latest software

Same, my PC renewing cycle used to be 2-3 years, now both my main desktop and laptop are 4.5 years old and there's little interest in replacing them. I bought computers since, but it precisely was for the form factor and not performance (my current job has me travelling about half of the year so I built myself a small but powerful 4.5kg mini-ITX rig I can take with me).
Heck I still even have my i7-970 build from back in 2010 stationed at a friend's, and use it there for the occasional game with him, still perfectly up to the task of running the latest games (2014 GTX970 though).

 

[Kilrah]

Do you mean... someone would do a knockoff of DJI? A knockoff of a Chinese company? Interesting.

No, what I said is that someone willing to compete with DJI would likely have to beat them on pricing for equivalent performance since there isn't much leeway to improve performance anymore.

But yes, that happens too. In the RC world you have one company called Jumper, and all their products are precisely based on those of other Chinese companies (Walkera and FrSky).

 

[Kilrah]

Active braking just means it doesn’t have to rapidly tilt the other way to brake.

No, active braking refers to actively slowing down the prop (and recovering the energy since at the same time another prop has to be accelerated anyway) instead of just removing power and letting it slow down on its own. Just like your Tesla example.

The aircraft cannot physically slow down without tilting in the first place...

 

[WithTheBirds]

Active braking just means it doesn’t have to rapidly tilt the other way to brake. I was just using it as an example but in a Tesla (probably other electric cars too but it’s the only one so I know anything about) when you pull your foot off the accelerator the car doesn’t coast it actually resists the forward momentum and the rotational energy is converted back into electricity, like a turbine, and recharges the battery with that energy which otherwise is lost due to applying the brake. Tesla’s almost don’t need brakes. Almost

So far as the drone braking in flight pay attention- it brakes by reversing pitch, often violently.

The regenerative braking I referred to, as described in certain of DJI's claims about sinusoidal drive ESC's (phantom 3 onwards) is substantially similar to the TESLA in principal. It has nothing to do with turbines. It simply switches the drive inverter to rectify the back emf from the motors.

 

[Former Member]

So far as the drone braking in flight pay attention- it brakes by reversing pitch, often violently.

How can a prop be reversed if it is fixed pitch?

 

[WithTheBirds]

How can a prop be reversed if it is fixed pitch?

LOL- I know your stirring but I will play along.... I never suggested the prop reverses. The pitch of the aircraft (often referred to as tilt angle) reverses. If it’s leaning forward to go forwards and you let go of the elevator abruptly it tilts backwards.

 

[Former Member]

LOL- I know your stirring but I will play along.... I never suggested the prop reverses. The pitch of the aircraft (often deferred to as tilt angle) reverses. If it’s leaning forward to go forwards and you let go if the elevator abruptly it tilts backwards.

Nah I dont stir just for the pleasure of it. Just asking for clarification.

 

[WithTheBirds]

Nah I dont stir just for the pleasure of it. Just asking for clarification.

Do you know off hand which motor drive SOC and inverter mosfets are used in the M2?

 

[Former Member]

Do you know off hand which motor drive SOC and inverter mosfets are used in the M2?

Want some pictures?

 

[WithTheBirds]

Want some pictures?

I will see how I go looking for teardown pics/videos but yes, if I have no joy pics will be appreciated. thanks.

 

[brett8883]

LOL- I know your stirring but I will play along.... I never suggested the prop reverses. The pitch of the aircraft (often referred to as tilt angle) reverses. If it’s leaning forward to go forwards and you let go of the elevator abruptly it tilts backwards.

Now we could be talking about two different things but what I thought you were talking about was the active braking on the Takyon SOC which the documentation goes into some detail about and says “Active Braking: The motor actively provides a reverse torque when decelerating, recovering some of the rotational energy. Normal braking mainly relies on air resistance.” https://dl.djicdn.com/downloads/tak...eed_Controller_User_Manual_v1.0_en_160331.pdf

Now I’ve never flown a drone with a Takyon SOC but I took that to mean that, say the AC is pitched forward at -15 degrees with the thrust angle pointed directly down through the body of the drone just like normal. But when it wants to brake it reverses the props momentarily to slow it’s forward motion with the thrust angle pointing directly up through the craft and then levels the craft and reverses the props again to come back to the normal direction. Maybe it still needs to reverse tilt just less? If you look at the props they are a lot like the M1 OG props which are more like blades. The M2 props with the winglet are clearly only designed to rotate in one direction.

But yea I guess that’s kinda what I had in mind actually but it doesn’t sound like the battery actually gets recharged it just uses less energy to brake. With a Tesla you could potentially charge an almost dead Tesla battery by rolling it down a large enough hill

 

[WithTheBirds]

Now we could be talking about two different things but what I thought you were talking about was the active braking on the Takyon SOC which the documentation goes into some detail about and says “Active Braking: The motor actively provides a reverse torque when decelerating, recovering some of the rotational energy. Normal braking mainly relies on air resistance.” https://dl.djicdn.com/downloads/tak...eed_Controller_User_Manual_v1.0_en_160331.pdf

Now I’ve never flown a drone with a Takyon SOC but I took that to mean that, say the AC is pitched forward at -15 degrees with the thrust angle pointed directly down through the body of the drone just like normal. But when it wants to brake it reverses the props momentarily to slow it’s forward motion with the thrust angle pointing directly up through the craft and then levels the craft and reverses the props again to come back to the normal direction. Maybe it still needs to reverse tilt just less? If you look at the props they are a lot like the M1 OG props which are more like blades. The M2 props with the winglet are clearly only designed to rotate in one direction.

But yea I guess that’s kinda what I had in mind actually but it doesn’t sound like the battery actually gets recharged it just uses less energy to brake. With a Tesla you could potentially charge an almost dead Tesla battery by rolling it down a large enough hill

Im not sure what your talking about- I was responding directly to your suggestion that you would like to see regenerative braking on DJI drones. I simply shared the seemingly relevant observation that DJI claims their drones already include this feature.

You don't need to imagine what is happing or guess anything- here it is in DJI's words "While the braking is happening, the motor is automatically put into generator mode so that instead of its mechanical energy being turned into heat energy and going to waste, it is turned into electric energy that is sent back to the battery, charging it up." Inside a Drone - ESC

To the extent DJI ESC are in fact implemented as advertised the operation is substantially similar to the principal employed in the Tesla.