HURRICANE 2.5 (2.5inch Cage Style FPV Drone Frame)
Updated: 4 days ago
Why there is a Hurricane 2.5 ? (Because even the DJI version can be built as 168gr including the naked GoPro 8 and 1404 motors, allowing batteries up to weight of 81gr until you reach the 250gr limit without compromising from the sturdiness.)
I am Hurcan (hence the name of the frame Hurricane :P) a professional videographer and I have been flying FPV Drones for a while now. The most I loved to use was a modified BetaFPV 95X (version 1). It flew great indoors and around people. However as my flying skills improved, clients wanted to see more acrobatic moves (which BetaFPV 95X is not really good at). So I started searching for quads which are able to do acro moves that still have a small footprint. Even though I found and tested a couple of them it was not satisfactory. So I decided to design a frame that fulfills my own needs. (versatility, agility, long flight time, sturdy, good at medium windy conditions and more importantly, safe)
After a couple of months and intensive testing, here is the final result, Hurricane 2.5. There are two versions which seem very similar to each other but still have some minor differences.
full videos available to inspect at the bottom of the post
What makes Hurricane 2.5 any different than other similar quad frames?
I think the best answer for this question is it's versatility followed by sturdiness and weight.
How versatile is Hurricane 2.5? * Pusher and normal configuration compatible, * 2 x 25.5mm*25.5mm and 2 x 20mm*20mm mounting holes, * 19*19mm camera compatible (on Digital version),
* Antenna mount (both bottom and top plate) is compatible with pigtail if that is a choice, * Naked GoPro can be mounted on top front, top middle and back bottom (in both pusher and normal configuration)
Digital Version Informational Video:
What are the hardware specs of Hurricane 2.5?
2mm carbon fiber all around
Total weight of carbon fiber plates 38gr (digital version) and 37gr (analog version)
Total weight of the quad(digital version) is around 168gr including 1404 motors, 5 blade props, 3d printed parts, AIO FC , de-cased Caddx Polar Vista and naked GoPro8.
Analog version comes around 154gr with Ghost Hybrid and analog camera.
How come it is lighter than other similar quads but still sturdier? In the first designs I see that I had to put extra standoffs to the corners of the quad where it seems to be most vulnerable to crashes. But it came with the cost of weight. So I decided to use 6x20mm aluminum standoffs at the center of the quad to keep it as sturdy as possible and put nylon standoffs(which handled really well in the crash tests) to the sides. Also used titanium screws at the main holes (motors, FC, Caddx Vista, aluminum standoffs) and used aluminium screws with the nylon standoffs. As a result this reduced the weight around 16gr which is something really big in a 2.5 inch quad.
What about all the carbon fiber out in the open? Since I am literally one guy trying to design this little flying object and introduce it to the wild, I am not capable of cutting foam or creating the frame in big batches.
So the best option I found for protecting the edges of the carbon fiber is using "moldable foam clay" This foam is generally used by Cosplayers but it seems it is really durable (ultra light silk version) And it adds only 4gr(when fully dried 24 hours later) to the weight when all the important parts are covered with it(available in different colors). At first I thought it looked bad this way but soon I realised that when flying close to people they are more comfortable with it when your quad looks like it is covered with marshmallows :D So I am keeping mine as is. (Also with better work it would look much nicer :) )
I will also include some 3d files at the bottom of the post if anyone is after a more agrassive look while protecting the edge of the carbon plates :) Screws, Nuts, Standoffs (There are lots of them...)
If you don't have weight considerations the most basic set of these would be;
38 x 5mm screws for standoffs,
2 x 4mm screws for camera,
12 x 4mm screws for motors (or 5mm depending on your motor choice)
4 x 12mm screws for decased vista unit (2mm frame+2mm nut+1mm board+5mm spacer+1mmboard+1mm nut)
4x 14mm (or 12mm) screws for the AIO
1 x 20mm normal screw (for naked gopro mount)
18 x 20mm AL standoffs
If you have a weight concern like me, this is the screw setup I use in this frame(168gr with decased Vista Polar and naked GoPro8);
24 x 5mm aluminium screws (for outer standoffs)
14 x 6mm titanium screws (for front, back and inner standoffs)
2 x 4mm titanium screws (for camera)
1 x 20mm normal screw (for naked gopro mount)
12 x (3*4) 4mm titanium screws (for motors)
6 x aluminum standoffs (for front, back and inner holes)
12 x plastic standoffs (for side holes)
with this change you can save around 12gr.
(all screws are m2)
AIO FC Choice
I have been a big fan of Jhemcu AIOs after many other brads failed on my quads. And all of my newer quads have "Jhemcu GHF405 PRO 3-6S F4 45A AIO Flight Controller" .
The reason I am using this AIO is becouse,
Huge Amp headroom with 45a
5v and 10v (not 9v) regulators on board
Readily available DJI port
25.5x25x mounting pattern
Capable of running at 8khzx8khz PID loop with DSHOT600 with max %23 CPU Load while using RPM Filtering.
I am guessing this particular Jhemcu AIO FC is not popular only becouse there is a problem with the Betaflight targets. Most of the sellers say it uses same target with Jhemcu405 but when you flash it the board does not work correctly. So you have to flash it with the custom config file which is prepped by the designer of the board to be able to use it fully.
Here it is if you are using this board.
How to flash it with custom config file; Say you are upgrading to BF 4.3,
Go to "Update Firmware" as usual
Select your Betaflight version while choosing JHEF405 as your board (this doesn't metter since we will be loading our own config)
Click load firmware online.
Than berfore flashing the firmware click "Load Firmware Local" at the right bottom of the configurator and choose the config file supplied above (JHEF_JHE405PRO_Config file). You will see " Loaded target, please load firmware file"
Than go to Betaflight version tab (where there are numbers like 4.3.0) and select something else (4.2.9 maybe?) and select the one you want again (4.3.0). This will refresh it.
Now, You are will be uploading Betaflight 4.3.0 HEX file with the custom target file and should be seeing "JHEF-JHE405PRO.config" before you click he "Flash Firmware" button.
And once you see that Binary is the Betaflight version you have choosen and the unified target is as shown in the picture you can click the "Flash Firmware" button and flash it.
I only tested 2 motor brands (T-Motor and BrotherHobby 1404s) with this frame and both are very similar in terms of flight characteristics but T-Motor seems to be a little bit more agrassive if you are nitpicking.
Only thing I can say is that if you are using only 3s batteries dont go below 4500kv.
If you are going with only 4s batteries 3800kv seems to be giving a nice smooth flight with wide throttle resolution while still keeping the ability to acro. If you are using both 3s and 4s batteries I think 4500-4800 kv are the best.
And motors with 1404 size seems to be the most suitable ones for this frame.
Digital Frame and 1404 4600kv motors early test
Analog Frame and 1404 3800kv motors early test
And here are some slooow flight battery tests:
7min 37sec with 4s 850mah
5min 24sec with 4s 600mah
5min 39sec with 3s 750mah
So, I think this is all there is about Hurricane 2.5inch frame. I hope you enjoy it. ah, by the way it is avaible to purchase at CNC Drones (they ship all arround the world) and you can reach me at firstname.lastname@example.org for UK orders and I will direct you to Mike. and you can find the 3d printable files here : https://www.thingiverse.com/thing:4950999 Happy flying :) Hurcan