Replay XD footage test

[Charles W. Hull]

Dean, where did you buy the Replay XD?

[Dean Sensui]

Charles... I ordered it directly from Replay. It says it's "in stock" now.

[Greg Boston]

Originally Posted by Dean Sensui

-- Smaller and lighter. I'm planning to put this on a small radio-controlled helicopter and need to keep everything as light as possible.

What size heli are you planning on mounting it to? Do you think a 400 series electric would be enough?

Thanks,

-gb-

[Dean Sensui]

Originally Posted by Greg Boston

What size heli are you planning on mounting it to? Do you think a 400 series electric would be enough?

Thanks,

-gb-

Hi Greg... It's going to be mounted on a T-Rex 450 SE V2. I had a GoPro with the housing mounted on it, and was able to fly it a bit, although I could tell that it was getting to the max payload capacity.

Here's an initial test flight. GoPro test 1.mov - YouTube

[Robert Turchick]

Mine is on a TRex 450 as well. Just keep your mOunt as light as possible and you'll be fine.

[Dean Sensui]

Originally Posted by Robert Turchick

Mine is on a TRex 450 as well. Just keep your mOunt as light as possible and you'll be fine.

Could you post a picture of how you mounted it? I have an idea that uses the existing Replay mount but haven't even gotten my hands on it yet. So I'm just taking a guess at how it could be done.

Also, is there any test footage?

[Robert Turchick]

Well, mine is probably overkill but seems to work well, It's 2 sets of small airplane landing gear with some lightweight crossmembers and wood dowels for skids.

I will be tweaking this a bit as the camera plate flexes enough to induce some camera shake. The biggest thing this design allows is easy removal of the camera (1/4-20 camera screw from the bottom. And it also allowed for a slight downward tilt to the camera which looks better when in a hover.
Once I solidify the mount I will be taking some test footage at a local park.
I'll post as soon as that happens. Finally starting to get below 110 deg here!

[Dean Sensui]

That's clean and simple.

Here's what I HAD set up with the GoPro. Since this photo was taken, it's been stripped down, the GoPro has been removed and things have been moved around.

I'm going to put the Replay in the same location as the GoPro but with a different mount. I might also try to see if I can come up with a way to isolate it from vibrations with a type of adhesive gel strip.

I'm trying to keep the camera as close to the main rotor shaft, and as close to the CG as possible. My theory is that the closer it is to the center, the smaller the amplitude of vibrations imparted to the camera.

The battery goes underneath, and I've extended the skids with tubular foam. It's lightweight and lifts the helicopter 1/2" to provide better battery clearance. It also provides me with a better sense of orientation since there's no canopy.

Below the camera is a real-time "FPV" camera to let me see what the heli sees in real time.

[Dean Sensui]

110 degrees??!!

[Robert Turchick]

Yup! Phoenix sucks during the summer and we had the hottest on record topping out at around 117 but averaging about 112!!

Yours looks cool to. I wanted to keep the camera directly below the main shaft for the CG reasons you mentioned. It required no trimming during hover testing which means it should fly just fine in forward. We'll see!!

[Greg Boston]

Good to know that the 400 size electrics will lift a GoPro. The one mod I would want to implement is flat bottom or at least, semi-symmetrical rotor blades, trading 3D performance for more lift.

Thanks for the info, Dean. Very helpful.

-gb-

[Robert Turchick]

Very windy day and also first true flight out of a hover. It's faster than I thought...even with all the extra rigging for the camera. Will do more on a calmer day to show what it really can do. Plus I need to shake the cobwebs off my thumbs! Haven't flown a heli this small in a few years!

TREXReplay Test 2 on Vimeo

[Dean Sensui]

You seem to have most of the vibrations tamed. Pretty good.

I'm doing something a bit different. The helicopter will be "split" between the frame and the skids. I made a special battery tray that's connected to the skids and the camera will also be mounted to the front end of that.

The whole assembly will have vibration isolating mounts... easier said than done. I have to design the mounts.

I might just make a stack of VHB tape. That stuff sticks REAL good when it has to, and very likely can replace bolts for this kind of application. The key is making it adhere to "high energy surfaces" such as metal. Aluminum is especially good, according to 3M's information.

[Robert Turchick]

Very curious to see how the iso mounts work. I have mounts for my motorcycle and the trailer hitch of my car. What i found with a bit of trial and error was that the hard mount worked best. Any looseness amplified vibration.

The other simple thing I could try with the heli is one of my shotgun mic iso mounts which the replay happens to fit in. Could be cool! Got a bit more testing to do with the current setup then I will change things up!

I think I'm also going to put the camera back to level rather than downward tilted. The lens is so wide it should be just fine.

Good to see I'm not the only tinkerer out there!

[Dean Sensui]

Originally Posted by Robert Turchick

Very curious to see how the iso mounts work. I have mounts for my motorcycle and the trailer hitch of my car. What i found with a bit of trial and error was that the hard mount worked best. Any looseness amplified vibration.

Here's a before-and-after test I did. One is with the Replay 1080XD hard mounted. The other with a vibration isolation setup I cobbled together.
Vibration test, T-Rex 450 and Replay 1080XD - YouTube

After re-doing the mount and centering the camera, here's another test flight.
Test flight, T-Rex 450, Replay 1080XD - YouTube