Looking for a frame or any kind of RTF/KIT etc that handles a 500g camera pointing downwards in front of the copter and with no obstruction above. Especially the gimbal part. The frame can always be built but any pointers is most welcome.
That’s a reasonably heavy camera.
A Daya/Alien 680 kit would do it, but depending on your appetite for DIY, I think following Mike Kelly’s project here: CANbus Quadcopter using UC4H : Son of FrankenSolo will yield superior results. (no pressure Mike)
It is really difficult to cantilever a gimbal off the front of any aircraft. Especially if the camera is 500g, then the gimbal to handle it will also be 500g or more. This will significantly mis-balance the aircraft. As James states the Daya H680 does have a mount designed to have a gimbal off the front but it is designed for a Gopro which weighs less than 100g and can use a 300g gimbal. You can use a big battery to help balance with weight but it is still tough to do. Most gimbals are designed to hang below with a suspension plate above so they don’t meet your requirement of “no obstruction above” so it would require a DIY effort as some people have done running the yaw motor on a bulkhead attachment creating the cantilever gimbal with no obstruction above. So I don’t think you are going to find anything that meets a RTF/KIT requirement without significant DIY rework.
I have seen folks use a big 800mm Tarot hex with Tarots rail system with extra long rails sticking way out the front but once again even with a big heavy hex it is hard to get it to balance. The balance really affects the quality of the flight characteristics.
You should seriously look at the Parrot Anafi which has the ability to move it’s camera 180 deg up and down off the front with a clear view straight up and straight down. The quality of the camera is very good. It is very small at 320g yet Parrot uses it for their commercial mapping value added business. You could not make a quad with it’s capabilities for it’s price with your requirement of no obstructions above and a straight down clear view.
Well, camera is only 386gr but i like to have good margin for future update and lense options.
Something like this i had in mind.
And a Y frame similar to this
Interesting topic and a question that I had been asking myself for some time now.
It seems that front-facing gimbal frames do have some significant drawbacks, however, they do have some pros too.
@ TB_RTK if it is not the secret, why do you need this kind of frame?
This kind of frame e.g. OCTA-V is especially good for inspection and mapping purpose (even though they are rarely used for mapping). This front facing gimbal allows you to mount GPS directly to the camera, or at least rigidly to the camera frame. The result of this is a really small lever arm offset. This would let you take the maximum from the UAV as a mapping tool.
Having the camera mounted to the gimbal hanging under the copter introduces some more effects like boresight misalignment, and of course long lever arm.
But it seems that you can’t buy such a frame anywhere online. Most of the OCTA-V frames that I have seen online are DIY. Though Trimble Falcon 8 has such a frame.
But the gimal to stabilize that Blackmagic is going to weigh 600g+. Hanging 1000g out the front of a multirotor is very difficult and still get it to fly well.
Take a look at the Parrot Anafi. When a company can build their own camera they gain a big advantage.
Thanks for the feedback.
The frame is for accurate mapping, hence to rule out the lever arm/time offset issue by placing the antenna above the camera. Camera need to have a front/downward pointing option.
The entire rigg must be under 2,5kg total mass.
At this point i have desided to use a tricopter configuration, 2 servos for the roll/pitch on the camera.
Camera will be suspended on a carbon fiber tube with ball bearing front mount, counteracting the roll and the servo a bit back to spread the load. This will give me a light weight gimbal with only one servo for the pitch with camera in front of the copter just below 500gr… i hope.
Check this out.
Note - I fixed the link.
Here a small uav working on ardupilot, however it has 4.8kg with all the gear. I am not sure it can face the front with the camera without having the props in the scene.
I think it works with the sony nex cameras that mostly have the weight of ~400g.
I was wondering why there is no frame similar to octo-v, but lets say with 6 motors - hexa-v.
I guess it is qute hard to make it work with such frames.
Dont think 500gr in the front is going to be a problem.
This one took of like a rocket with 500grams of crap in the front
The swedish rock
Yeah, this is exactly what we need! Bring back the analogous photogrammetry!
I mean, they are right in a way. If you use Y frame and a gimbal, I think that you should sacrifice yaw stabilization and go with the 2 axis gimbal, to reduce the weight at least a bit.
I would use a long quad H.
As the equipment might be expensive I would use a proved and stable solution.
Moving the camera to the front should not be a problem. You can allways keep the GC in its place moving the battery to the back.
Making the quad longer, would make tilt more stable, even if the camera is hanged to the front.
Something like this should fly smooth but it will go up to 5 Kg. with a 16000 mAh 6S battery.
Long_drone.pdf (78.2 KB)
I think H quad is the closest or my next option if Y frame doesnt do the job.
The total weight is a concern as i would like to keep it under 2,5kg total.
This gimbal solution is close to mine. I have the motor swaped with servoes. Clamps to hold the carbon tube is suspended with ball bearings and the servo is placed further back on the copter. The carbon tube on this picture is above the camera, i would flip it and move it behind the camera/gimbal
The picture you show as an example is a TurboAce Matrix (TurboAce.com). They have worked well for us but I’m not sure if they are still available.
I have a Turbo Ace Matrix as well. Tough little bird. Forward gimbal weight is easily offset by battery placement. It’s stable on all axes. Although I haven’t flown it since purchasing a Phantom 4 Pro. In my opinion, the the Phantom 4 Pro is a great platform for mapping 100 acres or less. Simple to deploy, very well integrated telemetry and video and reliable. Hard to beat for $1400. No I am not DJI dealer and I am a huge fan of Ardupilot.
TB_RTK, sounds like you doing more than mapping if you need a forward facing camera.
Forward for contructions task, build as, live camera feed for inspection etc
Some progress. Gimbal is ready for a manual test. Looks good