Krossblade SkyProwler Multi-Mission VTOL Transformer Drone
A transformer drone that hovers like a copter, flies fast and efficient like an airplane and transforms between the two configurations.
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Awesome Performance, Amazing Value
SkyProwler is a High-Performance Multi-Mission Vertical Take-Off and Landing (VTOL) Transformer Drone. It takes off like a multicopter, picks up speed using its high-powered thrusters, and then transitions to cruise flight on its high-speed wings. The multirotor take-off mechanism folds away in-flight giving SkyProwler super efficient aerodynamics and hence speed endurance and range far better than pure copters and on-par with pure airplanes.
But that is not all. Some missions require maximum hover time and tight turns in addition to great bursts of speed. Think of filming a car approaching a stopping point, and then going off again, think of filming pets and other animals running around, think of sports! No problem! Reconfigure SkyProwler without tools, by taking the wings off and changing the tail, or fly without tail, and what was the winged SkyProwler "Blade" configuration, becomes the wingless SkyProwler "Hornet" configuration. Hornet is a multi-copter so fast and agile that you can do things with it you can do with no other multicopter.
Paired with an optional ground station radio that gives you not 2 but 4 channels per stick and Eye, the world's first action cam with integrated gimbal stabilization (igs) and video quality up to 4k30, and you have a package so powerful, other aerial vehicles will get scared - except perhaps the F-22 Raptor.
Thank you for supporting SkyProwler!
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Vertical Take-Off and Landing
Vertical Take-Off and Landing (VTOL) enables aircraft to operate from virtually any environment. No runway is required. This opens up flying to a much larger range of possible terrains, from backyards and rough fields, over snow-covered mountains and sandy beaches, to a boat on the sea.
The problem with traditional VTOL machines such as helicopters and more recently multirotors is that they are slow and inefficient. This is because such machines always have to actively work to stay in the air, in addition to pushing themselves forward. Also, large rotors standing in the oncoming wind of a moving aircraft are very detrimental to aerodynamics and hence speed, endurance and range.
Winged aircraft like airplanes on the other hand are far more aerodynamic and they get their lift almost 'for free' from their wings. Winged aircraft can typically fly twice as fast as rotorcraft, stay in the air twice as long and have a range that can reach 4 times that of rotorcraft on the same amount of fuel/energy. Winged air travel can be just as energy efficient as travel by car, but it is up to 8 times faster!
Combining VTOL and winged flight is a fairly obvious theoretical idea. However, in order for this to make sense, the resulting vehicle must offer the best of both rotor-powered VTOL and winged flight, not a compromise. This is where the switchblade transformation mechanism comes in.
Switchblade Transformation Mechanism
The patent-pending switchblade transformation mechanism transforms SkyProwler from a multirotor craft with big, slowly moving rotors, excellent at VTOL and hover, into a pure, sleek and aerodynamic airplane excellent at fast and efficient cruise flight.
How does this compare to other VTOL mechanisms? You can find a more detailed discussion here: http://www.krossblade.com/disc-loading-and-hover-efficiency/
Briefly: The most well known VTOL mechanism for winged aircraft is the tiltrotor mechanism by which the propellers of an aircraft are tilted from vertical for take-off and landing, to horizontal for cruise flight. The issue with this is the following: VTOL works best with big rotors, in fact the larger the rotor, the less power it takes to lift a weight. Tiltrotor airplane propellers are typically larger than 'normal' propellers, but they are much smaller than those of say a pure VTOL craft, such as a helicopter. What this means is that tiltrotors can typically only lift 4 to 5 lbs (around 2kg) per horse power, while craft with more rotor area, can lift 10 to 12 lbs (around 5kg) per hp. This means bigger (and heavier) engines, more noise, faster down wash (down wash is the wind that blows in your face when for example a helicopter takes off). In cruise flight on the other hand, small propellers/rotors are best, because they offer the oncoming air less area to drag on. In effect, small fast spinning propellers are like 6th gear on a car - a lot of speed, but low torque. Big, slowly spinning rotors are like 1st gear on a car, little speed, but lots of torque. A tilt-rotor by analogy is hence not dissimilar from a car always driving in third gear. It works, but it burns more gas, is not as fast, and gets going more slowly.
For a more in-depth discussion of how different propellers/rotors suit different purposes please click here: http://www.krossblade.com/different-rotors-for-different-purposes/
The other existing mechanism employed for VTOL is called thrust-vectoring, and is used on jet aircraft such as the Harrier and the F-35. These aircraft are strictly built for awesome speed. As a side effect of that their engines are so powerful that it is possible to direct their jet thrust downwards in order to push the aircraft straight up for a vertical take-off. The problem: the effective lift area of the small nozzles and fans that direct the jet thrust is very small. Using the car analogy, these aircraft take-off in 6th gear. And so because of this all the 20,000 hp (or so) are needed to lift 40,000 lbs of aircraft straight up. The resulting noise is ear-deafening, it literally burns a ton of jet fuel, down-wash velocities reach 350 mph (550kph) and the down wash can be so hot that it can melt the concrete off the air strip from which they take off
To summarize the car analogy employed for different VTOL craft:
- Helicopters and multicopters always fly in '1st gear'
- Tiltrotors always fly in '3rd gear'
- Thrustvector systems always fly in '6th gear'
- SkyProwler (switchblade mechanism) takes off and lands in '1st gear' and cruises in '6th gear'
Videography with igs
The acronym igs means "integrated gimbal stabilization". We are always concerned about aerodynamics. If you hold your hand out of your car window at 50 or 60 mph (around 100 kph), you can appreciate the forces that fast moving air generates. This is why we designed a camera that minimizes aerodynamic disturbance. The result is the Eye cam. Eye has an integrated 2D brushless gimbal and anti-vibration mount, eliminating motors and other devices sticking out into the oncoming air. Brick-like shapes have the worst possible aerodynamic characteristics, this is why Eye is round and blends into the overall shape of SkyProwler. Integrating the gimbal into the housing of the cam also allowed us to use much smaller components like motors, which makes Eye uniquely light, just over a 1/3 of the weight of a GoPro (a great camera) with external 2D gimbal. Eye comes in two editions. The ProAm edition shoots quality video at 1080 resolution and 30 frames per second (fps). The Pro edition shoots cinematographic 4K at 30 fps. Both cameras have integrated gimbal stabilization (igs) and so carry the acronym igs. Eye ProAm: 1080p30igs. Eye Pro: 4K30igs.
Press Mention of Krossblade
Recently Krossblade has received attention from journalists for its work on future manned high-speed vertical take-off and landing personal aviation, including the unmanned prototype, SkyProwler. Below are a small number of examples.
- Payload: 1lb / 500g
- VTOL power systems: 4x130W, 1,500rpm per input Volt
- Thruster power systems: 2 x 180W, 3,000rpm per input Volt
- Servos: digital, metal-geared, with bearings
- Battery: 3 cell, 5,000 mAh
- VTOL propellers: 9 inch
- Thruster propellers: 5 inch
- Materials: Composites, carbon fiber, 7075-T6 aircraft aluminum
- Wingspan: 35inch/880mm
- Length of fuselage without tail and nose cone: 21inch/550mm
- Ground station radio frequency: 2.4 Ghz (FCC and CE compliant)
- Video down-link: 5.8 GHz (FCC and CE compliant)
- Ground station antennas: Directional
Krossblade Aerospace Systems is a start-up that originated at the hacker and makerspace heatsynclabs in Tempe/Mesa, Arizona. We are makers with a passion for aviation, robotics and emerging manufacturing methods.
SkyProwler has been under development for almost two years. Very early on (2013) we achieved VTOL and transition to winged flight with Prototype V0. However, in early 2014 with Prototype V1 we successfully tested the switchblade mechanism. Folding the rotors, motors and arms out of the way allowed for a far higher speed (+30%) and much longer range range (+50%) as compared to V0. Furthermore it made SkyProwler just as smooth and maneuverable as airplanes of the same size.
Risks and challenges
SkyProwler has been developed and tested for almost two years and most of the kinks have been ironed out.
The components we use are fairly readily available and even interchangeable, meaning should a component, like a certain electric motor, become suddenly unavailable during production then it can be fairly easily replaced with a number of similar options. This also means that future maintenance should be easy and cost-effective.Learn about accountability on Kickstarter
- (30 days)