Hi all!
We are glad to announce the start of crowdfunding campaign for Nimbus – racing drone with full carbon fiber monocoque body.
Please support us at: https://igg.me/at/nimbusdrone
Our website: aerodyne-rc.com
The Idea and the Impact of monocoque frames in racing drones.
Carbon fiber is well-known material for making drones, and especially racing ones. Conventional racing drone frame is made of layers of cut flat sheets of carbon fiber with aluminum or plastic stand-offs in between, openly holding the electronic components.
But we do the carbon fiber frame of a racing quad copter in a very different way - it is monocoque. Monocoque design is widely used for example in aerospace and automotive industries (airplanes and car bodies), it has high structural properties but very lightweight.
We see that monocoque design gives a new step to the drone racing as a new entertainment and growing sport with very high visual attractiveness. The main obstacle holding the drone racing to grow is the obsolete frames design. It is like first wooden airplanes, the bi-plane of Wright brothers from year 1903. Yes, the components are developing fast – new flight controllers, new motors and FPV cameras, but the fundamental frames development has stuck and going in circle for last couple of years. And the usability of flat-frames for drone racing is quite low. Flat carbon cracks and breaks down, during inevitable crashes, open electronics and wires are affected by environment – water, sand, dirt, snow, salt etc. Racing drone pilot spends more time in repairs and waiting for delivery of new components than flying. Having a number of spare drones for each race is not the most efficient way of growing, in terms time and money. Of course, it is hobby! I like building my quad! But sport will not go that way. It has to be an entertainment, and it shall be based on a very durable item with high usability (imagine usability and durability of a soccer ball, or baseball bat, or goalkeeper mask in ice hockey). And for the development of drone racing as a great hobby and sport it is important - if you want to fly, you need to fly! Survive the crash and fly again! Spend less time with wires and soldering iron, and more time flying! And it really seems, that future of drone-racing in not in the stick-built frames, but something else, something more durable and usable.
So, usability was the main design criteria for Nimbus drone design. And the realization is in the monocoque design for the frame.
What gives a monocoque frame to a racing drone?
First of all, it is strength. Monocoque is the best possible structural form to have best strength-to-weight ratio. Monocoque is basically a structural skin, is a structural system where loads are supported through an object's external skin, similar to an egg shell. The word monocoque is a french term for "single shell" or (of boats) "single hull". A true monocoque carries both tensile and compressive forces within the skin and can be recognised by the absence of a load carrying internal frame.
Early aircraft were constructed using frames, typically of wood or steel tubing, which could then be covered (or skinned) with fabric as lines or cotton. The skin added nothing to the structural strength of the airframe and was dead weight beyond providing a smooth sealed surface. By thinking of the airframe as a whole, and not just the sum of its parts, monocoque structures made sense and various aircraft companies soon adopted practices for building monocoque aircrafts.
In motor racing, the safety of the driver depends on the car body which must meet stringent regulations and a few cars have been built with monocoque structures. McLaren was the first to use carbon-fiber-reinforced polymers to construct the monocoque of the 1981 Mclaren P4/1, and in 1992 the McLaren F1 became the first production car with a carbon-fiber monocoque.
The same we have now for racing drones. We need strength, we need low weight, and we need to save our internal electronic components.
Nimbus –new step in racing drone design
Nimbus racing drone is a true monocoque of carbon fiber. We have some attempts on the drone racing market, which were partly carbon fiber monocoque, or looked like monocoque, or has very weak points in other aspects. Nimbus drone was not made in a hurry. It took more than a year of development and testing before we came to public.
Production of a monocoque form, and especially carbon fiber, requires significant initial preparations and investments. Therefore we started with small crowdfunding campaign to support first production run of Nimbus. We just started the campaign at Indiegogo 5th of December 2016. It will last for 30 days.
The backers of the Nimbus campaign will be able to get three alternatives of Nimbus drone: Frame only package, BNF - Bind-And-Fly package – assempled Nimbus to bind with your radio, and RTF – Ready-To-Fly – a package including complete Nimbus and TBS Tango remote control radio.
Strong, durable, lightweight, aerodynamically streamlined, weatherproof racing drone with enclosed electronic components and battery. Nimbus will become a game changer in drone racing.
If you understand the impact of new monocoque design in drone racing, please join our campaign!
“That is one small step for a drone, one giant leap for drone racing.”
Comments
Beautiful design, however, your rotor discs are way above the CG of the model. Probably a very fun and slow/sluggish flying end customer product but not a very stick responsive one in FFF. Other than that, a great idea, stellar execution and pretty darn good product, it's very close to being Great just incorporate a bit more of near center mass on Z axis and it will kick arse.
! Just my 2 cents
@earthpatrol, you definitely don't want to leave a naked carbon fibre composite just stting in the sun for a long time. The temperature of the part can easily reach over 100 deg C.
During flight the airflow should be enough to cool the airframe.
@Alex maybe let your airframe set in direct sunlight on a warm day and measure the the thermal characteristics internally as a bench mark maybe? 30C doesn't seem like a high enough ambient temperature test and with the external surface being black doesn't help. Do you have vibration measurements that you can share? Something that shows the motors running at different throttle levels and the raw sensor measurements of what the flight controller/sensor package is experiencing? Thanks.
earthpatrol , Thank you for your questions! There are no issues related to vibrations or heat. The modern ESCs works fine inside the monocoque body, without overheating, it was tested up to +30 C ambient temperatures. It does not stay absolutely cool, of course, but the temperature is within normal limits.
Vibrations is not an issue at all. Monocoque is much better in vibrations, rather than flat sheet carbon fiber.
For the radio signal - also no issues, since both antennas - FPV video transmitter (5.8 GHz) and control signal (2.4 GHz) - are located outside the body.
Yes, of course!
Is the battery replaceable in the field?
That looks great. Nice design. I'm curious about some of the physical dynamics related to heat and vibration. Do you have data related to a working prototype of your design? Does it stay cool internally? Are you able to isolate vibration to a level that would allow the airframe to be used for robotic flight? Have you found any issues with using a electronically conductive skin related to radio signal dynamics?
The aircraft looks great and all the best on a successful campaign. Cheers.