UAS Sensor Placement
Sensor placement is a critical
design decision based on the objective that an unmanned aerial system is tasked
to perform. In this paper, two
commercial aerial systems are discussed.
The first is the Yuneec Typhoon H, which is used for aerial photography
services to include full motion video and still pictures below 400 Above Ground
Level (AGL). The Second UAS is the First
Person View (FPV) Storm Type-A V2 racer to compete on a racing circuit. For the selection of these two drones the
blogs posted by Alexander Nixon about the two types of systems were very
informative and assisted in the evaluation of the various options.
Yuneec Typhoon H
The selection of the Yuneec Typhoon
H is made after the review of twelve (12) systems with similar capabilities in
the category of ‘Best Drones for Professional Film Making’ (Nixon, 2016b). Among the reasons for the choosing this
aircraft was the unobstructed 360-degree camera view, simplicity of operation,
and cost. This system has capabilities
found in more expensive professional solutions, but at a consumer price point. This
drone is suitable for both amateur and professional applications.
Vehicle
The vehicle is a six-rotor design
that has a range of one kilometer. The
maximum speed is 22 mph. The six-rotor
configuration make the vehicle more reliable in case of a motor or propeller
failure, making it safer to use over crowds.
Specification of the vehicle:
Material: Carbon Fiber
Wingspan: 16.1 inches
Weight: 4.1 pounds
Max speeds: up to 43.5
mph
Flight distance: 3000
feet
Battery charging time: 2
hours
Endurance: Up to 25 minutes
ST-16 Controller
The seven-inch Android based 720p
display works well in direct sunlight.
The user interface is rated as ‘excellent’ and is as good as the DJI’s
being responsive and intuitive (Nixon, 2016a).
You can control both the vehicle and the camera using the touch screen.
The flight control settings come preset. However, you can set and save new
flight control settings depending on your desired style. It has a HDMI output
for those that prefer to fly the vehicle with First Person View (FPV) googles.
Camera
The camera is a CGO3+ 4K Camera
Gimbal. It takes high quality and stable 4K video, and 12.4 megapixel still
images. The gimbal rotates through
360-degree range of motion. The camera
is capable of 98-degree field of view. Camera setting are adjustable with the
controller in-flight.
A unique feature of this system is
that the vehicle retracts its landing gear allowing a full 360-degree
unobstructed view, a significant feature for a system in the under $1500 price
range. This capability allows for the
way-point driven shooting, which is much easier to plan and execute (Nixon,
2016a).
Specifications:
Video: 4K UHD 30 frames
per second, HD 1080p at 120 fps, 100MB Video capture at 30 fps.
Camera: 12.4 MP, not
geotagged
Live View: 720 frames per second over a 5.8 GHz channel.
Gimbal: 3 axis anti-vibration with full 360-degree
rotation
Digital video
downlink: up to one mile.
Safety and Redundancy
In making an investment in these
types of aerial vehicle, safety and redundancy is important to secure the
investment. The Typhoon H has several
unique feature that distinguishes it from other systems. These features include: real-time object
detection and collision avoidance using Intel Sense Technology 3D; automated
flight modes; and two operator mode.
Intel Sense Technology 3D
Automated flight modes allows the
use of preprogram flight modes to best position the camera. These flight modes include:
Journey: This allows the vehicle to operate as far as
150 feet to take a selfie.
Orbit Me: The vehicle flies a
circular path, keeping the camera pointed at the center point.
Point of Interest: It will fly around a geographic position
based on GPS.
Curve Cable Cam: Vehicle flies
between pre-set coordinates, while the operator controls the camera. The
pre-set coordinates are both GPS and altitude. This is a preferred operating
mode of these vehicle as it allows for be best shot angles and easy transitions
during flight.
Follow me/Watch me: In this mode, the vehicle follows the
operator, while maintaining the camera fixed on their position.
Return to Home: The vehicle returns
and lands within 26 feet of the operator’s position.
Two-mode operation: Allows for the
vehicle and camera to be operated by different persons using a smaller
special-purpose controller (Nixon, 2016a, Typhoon, 2016).
Summary
The Typhoon H designed to provide the
sensor a full 360-degree gimbal rotation with 98-degree coverage is an
excellent platform for taking video and still photograph, all at a reasonable
price point.
Storm Type A V2 RTF
There are as many choices for the
First Person View (FPV) racing drone.
The decision on which type of drone to select is a bit more complex than
for photography. There are several considerations
that must be thoroughly researched and decided before the selection can be
made. These includes deciding on what
type of racing you desire, and whether you will formally compete in a racing
league or other informal events. There
are several different types of racing leagues for indoor and outdoor
racing. There are also rotor-cross, drag
and time-trail racing. Rotor-cross is
popular because it involves two or more drones on a racetrack at the same time
(Dixon, 2016c).
For most racing circuits, the 250 mm
(5-inch) mini-drones are the most popular.
This is not so surprising, since the smaller the drone, the more
maneuverable they can be. There are lot
of parameters that go into making a multi-rotor vehicle agile. The most important parameter that changes the
performance of the vehicle is the radius of the vehicle. Vijay Kumar in this famous Ted video explains
that the inertia of the vehicle is related to the angular motion of the vehicle,
which scales to the fifth power of the radius. The more you reduce the radius,
the more the inertia reduces.
Concurrently, the angular acceleration of the vehicle is inversely
proportional to the radius of the vehicle. As you reduce the radius the quicker
the vehicle can turn (Kumar, 2012).
You can only go so far in making the
radius of the multi-rotor small and also have enough lift and power to have a
viable drone. Manufactures have found
the radius to be about 125 mm. That’s one reason the 250 mm class of multi-rotors
is a viable size for racers. They can
make the vehicle fast and agile for the rigors of aero racing.
Since the author has no experience
in racing drones, the choice for this paper is the popular, affordable, and
ready-to-fly, Storm Type A S3 in the 250 mm class. There were other choices in the beginner to
intermediate level of proficiency level that also are great choices. They include Vortex 250PRO which is also
inexpensive, but requires assembly. At
the higher end, there is the Luminiere QAV250 G10, but you need to be an
experienced operator to fully appreciate the vehicle’s capabilities (Nixon,
2016c)
Vehicle
The vehicle has plenty of power and
endurance for its size. The flight
controller module (CC3D) onboard is responsive with minimal lag between the
controller and the motor sensors. This allows for direct response, which makes
the vehicle very agile. The specifications for the vehicle are:
Size: 230mm x 245mm x 60mm
Weight: 482 grams, 677 gram
including battery
Endurance 10.5 mins with standard
batteries
Communication
The vehicle control is on a 2.4 GHz
unlicensed frequency channel, while the data link is on a 5.8GHz channel. Each channel has sub-channels to avoid
interference from other vehicles operating in the same area. The communication channels operate up to 300
feet.
Controller
The RadioLink AT9 controller system
has 9 channels. It has preloaded modules
for easy setup. There is an optional 4.3
inch First Personal View monitor that attaches to the controller. It has a 5.0
Mhz bandwidth using DSSS spread spectrum protocol. The control range is up to
1.5 miles.
Camera
An unique feature to this vehicle is
the adjustable tilt angle camera with 700 TLV 90-degree field of view. The datalink transmit at 200 mwatt power,
allowing real-time video feeds of 300 ranges of 300 meters. The placement of the camera, and the
adjustable tilt angle option makes this vehicle a preferable option for those
that use the vehicle for FPV racing.
Summary
The Storm Type A
is a good candidate as a first buy racer because it is ready to go out of the
box. There is an upgrade to the Type A
Pro for those that want a faster and more responsive vehicle, which may be more
appropriate for someone with experience flying in the FPV mode. The unique
camera with adjustable tilt angle camera make it the appropriate choice for a
first-time FPV drone racer.
References
Kumar,
V. (2012, March 01). Vijay Kumar: Robots that fly ... and cooperate. Retrieved
June 16, 2016, from https://www.youtube.com/watch?v=4ErEBkj_3PY
Nixon,
A. (Ed.). (2016a). Yuneec Typhoon H Review: 6 is Better Than 4. Retrieved June
16, 2016, from
http://bestdroneforthejob.com/drone-reviews/yuneec-typhoon-h-review/
Nixon,
A. (Ed.). (2016b). Best Drones for Video & Film Making. Retrieved June 16,
2016, from
http://bestdroneforthejob.com/product-category/work-drones/pro-film-video-drones/
Nixon,
A. (Ed.). (2016c, May 01). Want to Race Drones? Read This Guide First!
Retrieved June 16, 2016, from http://bestdroneforthejob.com/drones-for-fun/racing-drone-buyers-guide-2/
STORM
Racing Drone (RTF / Type-A V2). (n.d.). Retrieved June 16, 2016, from http://www.helipal.com/storm-racing-drone-rtf-type-a.html
Typhoon
H. (2016, June 05). Retrieved June 16, 2016, from http://www.yuneec.com/Typhoon-H
