AirBlade Honeypot - The New Kind of CineWhoop
Do you remember that feeling when you watch videos from pro pilots and thought to yourself, 'How can I get such smooth videos out of my drones?'.
It's true that pro pilots are much better at stick control, their tunes are better, they are just better pilots overall. But let's not forget Reelsteady GO. The amazing stabilization software that makes your footage butter smooth!
The Original Cinewhoop
The Shendrone Squirt and many other similar platforms were designed to take advantage of the amazing combination, GoPro Hero 6 + Reelsteady GO. These platforms are meant to be flown indoor, or around people, due to having 3D-printed ducts. However, these platforms can only work to their fullest potential when the ducts are designed properly to produce additional thrust. More often than not, you find these ducts acting more like bumpers or prop guards because they don't have the correct aerodynamic properties.
Having designed and flown a 'cinewhoop' ourselves, there are a few things that really bugged us about this platform which we will outline below. But thankfully, almost pure luck, a new 'innovation' was taking root within the community which prompted us to push ahead with our AirBlade Honeypot design. This new 'innovation' is the Naked GoPro.
We believe the first and original Cinewhoop ever designed was the Shendrone Squirt, which was designed to carry a full size GoPro for commercial filming operations. Now let's look at the rationales behind the Squirt design, and many similar platforms that come after, including our IntreWhoop:
- We have to carry a heavy GoPro (~120g) but the frame has to be small enough to be flown indoor and around tight gaps. That means this is a 3 inch frame, it's a good compromise of size and potential power.
- The platform must be safe enough to be flown around people and indoor around objects. This means it needs some sort of bumpers or prop guards, possibly from a soft material like TPU or even foam.
- The quad has to be able to lift 150g-200g worth of payload (GoPro + ducts) comfortably and be able to fly for a reasonable amount of time. This means 1407 or similar size motor and at least a 850mAh 4S.
- The bumpers or prop guards are adding extra weight to the build, so in order to eliminate some of the weight penalty, aerodynamic ducts can help providing additional lift.
- Taking into considerations all of the requirements above, a platform like the Squirt seems like the best design for the job.
Shendrone Squirt and similar platforms work. They do the job just fine. But there are drawbacks that we found:
- TPU ducts are heavy. They're also finicky to design and print. If the gaps between the props and the ducts are not optimized, the ducts basically just act as bumpers and don't really produce additional lift.
- Ducts are LOUD! Especially if you actually design it correctly.
- The drones are extra susceptible to wind because ducts produce lots of drags.
- The overall platform is quite heavy
But luckily, as I mentioned above, all of this would have been fixed with the Naked GoPro. The Naked GoPro strips away all the unnecessary weight of a GoPro without compromising the video quality that GoPro camera is known for, and best of all, it still works with ReelSteady GO. A 120g GoPro is now only 30g, that's some substantial weight savings! You can easily strip our GoPro and use one of the BetaFPV GoPro Lite Kits for that.
So now what?
AirBlade Honeypot - The New Kind of Cinewhoop
The original AirBlade Honeypot was designed in 2015, back then, it was just meant to be something to be flown indoor. We sent a couple of prototypes out to our test pilots but we never went ahead with the production.
Fast forward to March/April 2020 when we first saw the Naked GoPro. It was like 2 ideas just clicked together perfectly. Here is our vision for the new AirBlade Honeypot:
- Compatible with DJI system
- Because the Naked GoPro (with casing) is only ~30g, we don't need a huge 1407 motors to carry it. We could be looking at smaller motors like 1404 swinging 2.5 inch or 3 inch props and it would still produce more than enough lift to carry the camera
- Given that it only runs 1404 or smaller motors, we can easily use a AIO Toothpick flight controller like the BetaFPV Toothpick 20A AIO or the 12A version of that board to save weight and space
- Given that 1404 at the right kV can be fairly efficient, we can even use smaller battery like 550mAh 4S or 650mAh 4S and still achieve satisfactory flight time
- We don't necessary need the ducts for additional lift. We could use carbon fibre prop guards with some TPU bumper for indoor use
- The carbon fibre prop guards reduces the weight penalty as well as remove unnecessary drags created by the ducts before
- We can have pusher configuration
- The overall platform can be sub-250g.
So as we embarked on the redesign of the AirBlade Honeypot, we made the following design decision:
- We want the frame to be as light as possible so the best compromise is 2mm carbon fibre all around. It is rigid when cut right, which is more than enough for a filming rig that won't be crashed repeatedly.
- Because it's 2mm carbon fibre, to increase the strength of the frame, our layout combines X-frame design and brace structure. That allowed us to have narrower arms (meaning lighter frame) without compromising the durability.
- We want it to be affordable. So that means no 3D printed pods, no 3D printed bumpers or prop guards, instead it should be carbon fibre prop guard. Some of the prop guard designs we see out there have a whole bottom/top plate with the prop guard cut. Most of the material is milled away but you will pay for the full sheet of carbon fibre. Therefore we decided to make it a modular design. The guard is broken into 3 separate pieces that are fastened together. This modular design means it can be cut efficiently from the same sheet of carbon fibre, reducing the overall cost.
- We want it to be compatible with DJI system, more specifically, the Caddx Vista for those who just want a nice HD-capable frame, instead of GoPro footage.
- Available in both 2.5 inch and 3 inch
And after several revisions, we came up with this
What you see above is the 2.5 inch version. The 3 inch version is posted below.
As you can see from the CAD design, our original idea was to have dual stack layout. The problem with that is the prop has to clear the body, which means larger wheelbase. After receiving feedback from Gab_707, we're gonna try to make it as small as possible, which means removing the dual stack layout possibility without removing DJI compatibility.
Our next revision is coming up soon. Stay tuned!
UPDATE 1 (June 26 2020)
We took feedback from Gab707 and made some small changes to the design. The goal here is to have the smallest form factor possible. So we remove the ability to build 20x20 stacks on the same plane as the motors (pusher config). Instead, you have the ability to build a 26x26 central stack under the bottom plate, and then 20x20 on top of the bottom plate. The top plate is optional because you could technically build a full 26x26 central stack (AIO+Vista) below the bottom plate.
A feature that we also put in is the adjustable HD+FPV camera mount. Specifically this accommodates the BetaFPV GoPro Lite and DJI HD Camera (a version for Caddx Nebula is available as well). With this mount, you can also do negative camera tilt which is useful when you're chasing a mountain biker or skier downhill.
Here are some photos of one of the possible configurations