Why no Bluetooth connection to RC from phone?

[Wanbli]

It seems to me that connecting the phone/tablet to the Remote Controller via Bluetooth or Wifi would be much simpler and would eliminate all the connection issues that we experiance with bad cables and connection ports. the Phone/Tablet is always inches away from the rc, so it should stay connected. The connection from the "Motion Controller" is wireless, why not the Remote Controller? We DO have the technology to make this a reality. Can someone tell me why we aren't using it?

 

[MA2 317]

It seems to me that connecting the phone/tablet to the Remote Controller via Bluetooth or Wifi would be much simpler and would eliminate all the connection issues that we experiance with bad cables and connection ports.

I started with a DJI Spark in 2017 and it was a wireless Wi-Fi system.

No cables.

Bluetooth signals had an adverse effect on the operations of the Spark connection between the device and remote.

The Go4 app would tell you about it when BT was detected.

Part of the checklist before the flight was to eliminate BT and other Wi-Fi related stuff so the Spark could perform better.


If you flew in a Wi-Fi / BT congested area, the Spark may encounter connection issues due to the other signals in the air.

Fun times trying to fly at a resort when everybody is wearing a smart watch, fit bit, headphones, etc.


Then somebody stuck an OTG cable in and it helped having a hard wire connection verses the wireless.



That was 2017 wireless tech and it had drawbacks back then.
May be similar today?

.

 

[Droning on and on...]

I think @MA2 317 misunderstood. The question was about the connection between phone –running Fly or GO4 – and the remote controller/transceiver with the physical control sticks.

This has always been via a physical cable.

The reason neither BT or WiFi are used is because no matter how close the two devices, the environment can still cause disconnects noise and other reliability issues.

Bluetooth further has latency problems that would cause unacceptable delay in control response.

The connection between the phone and the RC is too critical to take any chances.

 

[MA2 317]

I think @MA2 317 misunderstood. The question was about the connection between phone –running Fly or GO4 – and the remote controller/transceiver with the physical control sticks.

Not misunderstood at all.

It was wireless.

The Spark used two Wi-Fi signals.

1, Between device / remote.
2, Between remote / Spark.

It was the local BT interference that would interrupt the wireless connection between the device and remote that would be the problem.

This has always been via a physical cable.

No. It was not wired.

DJI refused to accommodate the use of an OTG cable on the Spark for the longest time because it was the portable selfie aircraft that didn't need a remote. You could fly with just the phone.

DJI gave in because a hard wire was much better between the device and remote, eliminating one of the Wi-Fi signals.

Visit the Spark Pilots forum about the history of the Spark.

It was a cool little flying brick back then.

DJI Spark Drone Forum

DJI Spark Drone Discussions, Support, Forum and Online Community

sparkpilots.com

.

 

[Yorkshire_Pud]

It seems to me that connecting the phone/tablet to the Remote Controller via Bluetooth or Wifi would be much simpler and would eliminate all the connection issues that we experiance with bad cables and connection ports. the Phone/Tablet is always inches away from the rc, so it should stay connected. The connection from the "Motion Controller" is wireless, why not the Remote Controller? We DO have the technology to make this a reality. Can someone tell me why we aren't using it?

I'd go with a wired connection every single time.
Given the number of complaints one reads about establishing suitable wireless connections for "quick transfer" etc. wireless seems to be a nightmare.

 

[Wanbli]

Thanks for the quick responses!
Seems there's little to no problems with the Motion controller.
I repair the 1st gen dji drones, and one of the most common issues is related to the micro-USB port or cable. Today I had one with the usb-c connector on the Air2s controller and there seems to be major issues with the usb-c port and the cable that connects to it. That's what made me think of this question?

 

[Droning on and on...]

Thanks for the quick responses!
Seems there's little to no problems with the Motion controller.

The MC doesn't use BT or wifi.

 

[Wanbli]

Ok, I think you are missing the point, I used those two as examples. The point being it's a wireless connection. In fact, all connections, video, Control and data are wireless over extreme distances, except for the phone to controller. Which is the shortest distance...

 

[Droning on and on...]

No, I get your point.

There is so much more in play than just "wireless". In particular in this case, transmission protocol.

BT and wifi are not reliable protocols for real-time control applications. So they don't do that very well. They're designed to move data, so they're engineered to deal gracefully with packet loss and recovery, distinctly non-real-time operations.

This is why DJI developed Occusync. Engineered with real-time control in mind. A lost packet now and then isn't recovered by the system, you don't care. What you care about is the next packet(s) being transmitted are received and acted upon immediately (control data) or displayed (video).

Occusync will ignore lost packets to the degree it doesn't compromise control. For video, there's no reason to recover anything that didn't make it to display in real time.

 

[Wanbli]

Excuse me for asking, I'm just a stupid Moron.

 

[Cafguy]

If you have ever had the chance to fly a D.J.I. Ryze TELLO With a Gamesir bluetooth controller you will see pretty much what a controller connected via bluetooth is like ( It lags ALOT) Not really an issue with a little cheap drone but I wouldn't pay for a More expensive drone with this type of setup its not reliable at all

 

[Felix le Chat]

Ok, I think you are missing the point, I used those two as examples. The point being it's a wireless connection. In fact, all connections, video, Control and data are wireless over extreme distances, except for the phone to controller. Which is the shortest distance...

The shortest distance will give the strongest signal between Bluetooth devices. The same RX signal (Bluetooth) between the drone and the controller is weaker because the drone has to transmit it back to the controller over a considerably longer range. The signal between the screen device and the controller swamps the control transmission beyond a certain distance.

 

[DARKSeifer]

Obviously because it would generate massive interference with the drone signal. Phone in airplane mode connected through a cable to the controller will give you the best signal performance at the lowest input lag and the highest bandwith possible.

The phone is literally clamped with the antennas and if you use Wi-Fi, BT, or LTE drone signal performance decreases heavily, lagging even at close range because all those antennas work at about the same frequencies.

 

[Wanbli]

Perhaps I should have said "wireless" instead of Bluetooth or wifi in my OP. Obviously everyone responding is happy with the current phone to controller connection and the associated issues.
Thanks for your time and responses.

 

[MavicAir2Marc]

Video transmission is a data hog (especially at higher resolutions). For reasons stated earlier, bluetooth or wifi have lag compared to a wired system. Video signal will drop out before your control signal just because of how much data is being transmitted and the quality of the signal required. If BT or wifi were better for that, then DJI would have implemented it long ago. Not to mention it would cut down on the phone compatibility excluding lower powered devices because they wouldn't have the power.

 

[Droning on and on...]

Excuse me for asking, I'm just a stupid Moron.

Huh?

If directed at me, I certainly don't think so.

 

[Droning on and on...]

Video transmission is a data hog (especially at higher resolutions). For reasons stated earlier, bluetooth or wifi have lag compared to a wired system. Video signal will drop out before your control signal just because of how much data is being transmitted and the quality of the signal required. If BT or wifi were better for that, then DJI would have implemented it long ago. Not to mention it would cut down on the phone compatibility excluding lower powered devices because they wouldn't have the power.

If DJI could make your phone do Occusync, they could get rid of the wired connection. And like the goggles with DJI FPV systems, DJI Fly could receive and display the live video stream directly on the phone without having to go through the RC.

One problem (among many) with either BT or wifi for this application is it doesn't prioritize telemetry and control signals over the video stream in the protocol design – it's all just data.

I don't know the internals of Occusync, but id bet money telemetry is wrapped in all sorts of error recovery that the video stream is not, explaining why you can completely lose the video feed but stil be receiving telemetry, something I've experienced more than once. I expect control signals going the other way are made similarly robust.

Alas, DJI would have to have low-level access to the SDR in the phone hardware, which ain't gonna happen, and it's impractical anyway with the plethora of phone models out there.

So, cables.

 

[Fort Worth Boy]

It seems to me that connecting the phone/tablet to the Remote Controller via Bluetooth or Wifi would be much simpler and would eliminate all the connection issues that we experiance with bad cables and connection ports. the Phone/Tablet is always inches away from the rc, so it should stay connected. The connection from the "Motion Controller" is wireless, why not the Remote Controller? We DO have the technology to make this a reality. Can someone tell me why we aren't using it?

I am only ashamed of myself for not wondering those same things. I just bought a stupid pouch to hold my cell phone so I can fly my Avata. (has to be connected all the time) With more and more remote ID on the horizon we are going to wind up hanging ourselves in our cables.

 

[hiflyer201]

MA2 317" data-source="post: 1544907" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch">

DJI refused to accommodate the use of an OTG cable on the Spark for the longest time because it was the portable selfie aircraft that didn't need a remote. You could fly with just the phone.

DJI gave in because a hard wire was much better between the device and remote, eliminating one of the Wi-Fi signals.

Hey Indiana, I'd forgotten the big deal with the OTG cable. I still have my spark and I fly it in the house with my phone occasionally. It sharpens up the stick skills without fancy levers. I always have to get the manual out when switching between the phone and the controller. It was a nifty little machine though and I'm still impressed with the camera.

 

[Kilrah]

The transmission between the aircraft and remote is good because it uses dedicated hardware and protocols. Wireless connection to the phone would be limited to what the phone has built in, and that's well known to be way inferior. The rare wired connection issues would pale in comparison to those you'd get from wireless operation.