DJI Phantom 2 with OEM retractable gear!

[Tipo815]

After pestering my local RC shop to engineer a retractable OEM (did not want one of those ugly aftermarket skids) landing gear system they finally came through with a very slick design. No more skids in the corner of your videos plus there's the cool factor which is undeniable!

http://youtu.be/WmMJpas1WD0

 

[cruz_ctrl]

After pestering my local RC shop to engineer a retractable OEM (did not want one of those ugly aftermarket skids) landing gear system they finally came through with a very slick design. No more skids in the corner of your videos plus there's the cool factor which is undeniable!

http://youtu.be/WmMJpas1WD0

no denying the cool factor but I have never had the problem of skids in vids...

 

[paulajayne]

Already been done way back in Feb this year.

[youtube]https://www.youtube.com/watch?v=vTcs5LmsXao[/youtube]

 

[varmint]

And these are deployed using what free channel?

 

[stevet]

Sexy.. how about a bit more info

 

[paulajayne]

Info is in the posts on the you tube link - it will mess with the compass though.

 

[Tipo815]

After pestering my local RC shop to engineer a retractable OEM (did not want one of those ugly aftermarket skids) landing gear system they finally came through with a very slick design. No more skids in the corner of your videos plus there's the cool factor which is undeniable!

http://youtu.be/WmMJpas1WD0

no denying the cool factor but I have never had the problem of skids in vids...

Either you're not using a GoPro or perhaps you haven't flown at very high altitudes on a windy day. I've flown at 2500 feet out in the middle of the ocean and when doing a 360 at that altitude the wide angle GoPro shows a skid in the corner.

Already been done way back in Feb this year.

I know. I've seen this video but he created a "one off" home made retractable system (antiquated by comparison) versus a well engineered "production" piece like the one created by the RC shop.

And these are deployed using what free channel?

As you know there's no free channel so they've engineered a new board that doubles the use of the CL/HL channel. The actual function is an activate/deactivate HL sequence to lower and raise the gear. Both CL/HL remain fully functional.

Info is in the posts on the you tube link - it will mess with the compass though.

The compass is relocated onto a custom carbon plate and so far it has had no negative effect on the compass during flight. So no ... it does not mess with the compass in terms of interfering with the signal but yes ... it does mess with it in terms of relocating it.

 

[rjstone]

Well, this certainly looks much more "blade runner" than usual...

 

[OI Photography]

Any idea how much they weigh?

They do seem to fit the Phantom nicely, but I'm not sure how a custom aftermarket solution qualifies as OEM.

 

[Tipo815]

Any idea how much they weigh?

They do seem to fit the Phantom nicely, but I'm not sure how a custom aftermarket solution qualifies as OEM.

I think they said about 75 grams. Not light but doesn't seem to affect flight.

The "OEM" designation I'm referring to is the landing gear/skids and not the application/modification. Until now the retractable gear applications (aftermarket) have been ugly and ungainly looking. The modification to the OEM skids is clean and they even look as if they were an "OEM install" in my opinion.

 

[OI Photography]

Any idea how much they weigh?

They do seem to fit the Phantom nicely, but I'm not sure how a custom aftermarket solution qualifies as OEM.

I think they said about 75 grams. Not light but doesn't seem to affect flight.

The "OEM" designation I'm referring to is the landing gear/skids and not the application/modification. Until now the retractable gear applications (aftermarket) have been ugly and ungainly looking. The modification to the OEM skids is clean and they even look as if they were an "OEM install" in my opinion.

Understood, that makes sense...I'd misread it initially.

Those are the ones with the little machined bracket for the compass as part of the assembly on one side, yes?

 

[varmint]

That's a really nice, super-clean kit, but I see a couple of concerns (in addition to the $250 pricing).

How would the IOC switch operation play with things like resetting home point. Since resetting home requires a 5x IOC toggle, then it seems like the retracts would deploy when trying to reset home?

Also, it doesn't appear (at least from anything mentioned there), that there's any failsafe operation. If the gear is up when you lose a control link, or hit critical power levels outside of visual range, and the phantom is forced to land, you could very well auto-land on your camera.

The micro servos being used are going to be very low torque. Even in the video I could see the deployed legs moving with what appears to be very little force (under power). Are these things going to be stable enough to land on? The stock DJI leg design is an unstable one to begin with.

All that being said, I'm probably going to order this anyway

 

[OI Photography]

I'm also very curious how they managed to repurpose the IOC switch, where do they obtain the signal input or output for that?

 

[varmint]

I'm also very curious how they managed to repurpose the IOC switch, where do they obtain the signal input or output for that?

If you look at the installation video, you should see a "device" with 4 leads. 1 lead goes to the RX, the other to X2, and the last 2 to the servos. The "device" is probably an Arduino which reads the PWM on the IOC channel and counts the pulses in conjunction with a timer. When it counts x pulses within a given period of time, it sends a high (or low) out to the servo.

This is why I have concerns about the "do this x number of times to raise or lower" approach, as it will definitely get in the way of home lock reset.

 

[Tipo815]

That's a really nice, super-clean kit, but I see a couple of concerns (in addition to the $250 pricing).

How would the IOC switch operation play with things like resetting home point. Since resetting home requires a 5x IOC toggle, then it seems like the retracts would deploy when trying to reset home?

Also, it doesn't appear (at least from anything mentioned there), that there's any failsafe operation. If the gear is up when you lose a control link, or hit critical power levels outside of visual range, and the phantom is forced to land, you could very well auto-land on your camera.

The micro servos being used are going to be very low torque. Even in the video I could see the deployed legs moving with what appears to be very little force (under power). Are these things going to be stable enough to land on? The stock DJI leg design is an unstable one to begin with.

All that being said, I'm probably going to order this anyway

Most of you guys know (way) more than I will ever know when it comes to the "electronics" involved in the Phantom. I'm one of those guys who tells my RC shop what I'd like my Phantom to do and they install whatever components it needs to turn my desires into reality (ie. long distance control and long range FPV).

When I saw the video of the guy who made the "home made version" of the retractable OEM gear I showed it to my RC shop and basically begged them to make me a "one off" system. That idea turned into the production piece they are now selling. I agree that $250 seems a bit on the steep side but the components are really nice pieces (in my amateur opinion). It seems like there is definitely some engineering that went into making the kit and I guess the value to us as consumers will vary from person to person.

As far as the Phantom itself I've only flown it once since installing the gear and so far nothing appears to be any different (ie. weight of new components, compass, home lock, etc.). I cannot comment on anything related to the servos and electronics other than everything seems to work fine. I do agree that the landing gear is no longer as durable as when it was fixed and this could pose a problem if you don't land well to begin with. So far I've never had any issues landing (ie. Phantom tipping over or landing hard/crooked) so I can't comment on the durability of the retractable skids as opposed to them being fixed. I do occasionally "grab" my Phantom out of the air and I have to try this with the retractable gear. I think it would definitely be less durable in this instance but I'll have to reserve comment on that until I try it.

As far as the electronics go I have zero comment on this now and that won't change later since I know nothing about what went into adapting the toggle switch to work with the landing gear and still remain usable in the CL/HL positions.

 

[OI Photography]

The "device" is probably an Arduino which reads the PWM on the IOC channel and counts the pulses in conjunction with a timer. When it counts x pulses within a given period of time, it sends a high (or low) out to the servo.

Perfect, thank you, that was I was trying to figure out.

 

[varmint]

When I saw the video of the guy who made the "home made version" of the retractable OEM gear I showed it to my RC shop and basically begged them to make me a "one off" system. That idea turned into the production piece they are now selling. I agree that $250 seems a bit on the steep side but the components are really nice pieces (in my amateur opinion). It seems like there is definitely some engineering that went into making the kit and I guess the value to us as consumers will vary from person to person.

Interesting story, and I wish I had the resources to order "one-off stuff" myself. I hate to think what you must have paid for the service, but it's cool they there are people out there willing to do things like that. I also like the engineering. It' very very clever.

Again my only concerns are with the strength of the gear under those small servos. It may be possible to buy much higher quality micro servos with way higher torque, but at the same time, I would have expected a system that costs $250 to come with the absolute best servos available.

Also, when I speak about interference with IOC functions, I'm not talking about being able to set course lock, home lock or OFF, I'm talking about the "other" IOC function which is toggling the IOC switch 5 times in order to reset the home position. That ability (I believe) won't work with this setup because the gear is also looking for a series of toggles. In other words if I try to reset home point, it's going to extend or retract the gear The workaround would be to get in the air before resetting the home point - so not a show-stopper.

The real "show stopper" may be the fact that the gear deployment is not tied into failsafe/RTH. You have to be guaranteed that the gear is down when that occurs, and in this case, I'm not seeing anything that indicates it cares or knows about it.

Anyway I ordered one because I intend to experiment with the "module" to see if I can get it to deploy my own retracts. If it works, I may try the same approach using an Arduino, and maybe add some safeguards like a barometer and accelerometer that can deploy the gear in an emergency.

 

[OI Photography]

Anyway I ordered one because I intend to experiment with the "module" to see if I can get it to deploy my own retracts. If it works, I may try the same approach using an Arduino, and maybe add some safeguards like a barometer and accelerometer that can deploy the gear in an emergency.

I def understand the concern about having the gear down if RTH is ever triggered w/the stock Phantom controller, but with all the cost and effort you're talking about wouldn't be easier and cheaper to just use an aftermarket Tx/Rx that will let you control the retracts independently of the NAZA, where RTH won't affect your control of them? Some even have the ability to let you use barometer or other telemetry-based data to trigger the retracts (or anything else for that matter).

 

[varmint]

I def understand the concern about having the gear down if RTH is ever triggered w/the stock Phantom controller, but with all the cost and effort you're talking about wouldn't be easier and cheaper to just use an aftermarket Tx/Rx that will let you control the retracts independently of the NAZA, where RTH won't affect your control of them? Some even have the ability to let you use barometer or other telemetry-based data to trigger the retracts (or anything else for that matter).

It would be easier, unfortunately it's impossible on an Vision because of the 2.4Ghz band being used by the VTX. Anyone who's ever tried to use a Futaba or similar 2.4Ghz TX with the Vision or V+ has met with interference. One alternative is to use UHF (e.g. Immersion's EzUHF or DragonLink), but the problem with that is that DJI disabled PPM on the Vision series. That rules out using any of the UHF options. Believe me, I've tried it all.

 

[OI Photography]

I def understand the concern about having the gear down if RTH is ever triggered w/the stock Phantom controller, but with all the cost and effort you're talking about wouldn't be easier and cheaper to just use an aftermarket Tx/Rx that will let you control the retracts independently of the NAZA, where RTH won't affect your control of them? Some even have the ability to let you use barometer or other telemetry-based data to trigger the retracts (or anything else for that matter).

It would be easier, unfortunately it's impossible on an Vision because of the 2.4Ghz band being used by the VTX. Anyone who's ever tried to use a Futaba or similar 2.4Ghz TX with the Vision or V+ has met with interference. One alternative is to use VHF (e.g. Immersion's EzUHF or DragonLink), but the problem with that is that DJI disabled PPM on the Vision series. That rules out using any of the UHF options. Believe me, I've tried it all.

Oh well yeah for a Vision/Vision+ it's a whole different ball game

I guess the only other option (and not an optimal one) would be to use a retail NAZA v2 so you can do the EzUHF by PPM....that or get them to finally release a version with S-bus :roll: