UAS Sensor Placement

The field of unmanned aviation has expanded rapidly over the last two decades. Small unmanned aerial systems (sUAS) are the largest segment of unmanned aviation, and arguably unmanned systems in general, and their exponential growth has contributed to a blossoming hobbyist and commercial market. With so many choices on platforms, where does a new unmanned pilot start when searching for a suitable aircraft. There are certainly many uses for sUAS, so addressing all wouldn’t be feasible with a single paper. This work will focus on two of the most common uses for sUAS and offer suggestions for viable platforms.

The first use examined will be from the commercial side of unmanned aviation. From the onset of unmanned system use in aviation unmanned aerial systems (UAS) have been used in large part for remote imagery platforms. UAS have served the military well as intelligence, surveillance, and reconnaissance (ISR) platforms, so it’s no surprise operators saw value in aerial imagery collection for commercial use. Aerial photography/videography is a very popular use for commercial sUAS operators. There is a litany of unmanned systems commercially available, many of which are capable aerial camera platforms, making selecting platform a challenge.

A proven industry leader in sUAS is DJI. The firm produces high quality aerial photography drones. The Phantom 4 Pro (see Figure 1) is one of their commercially available platforms that strikes a good balance of aerial film making ability and modest price. The sUAS is a satellite navigation equipped quadrotor multi-copter capable of a high level of autonomous function (Phantom 4 Pro, 2017). The aircraft has an integrated 5-direction obstacle sensing system and is designed for 4-direction obstacle avoidance (Phantom 4 Pro, 2017). The key feature of the system, however, is the camera. The three-axis, gimbal mounted camera utilizes a 1-inch 20-megapixel complementary metal oxide semiconductor (CMOS) sensor and is capable of filming in 4K resolution at a rate of 60 frames per second as well as taking still photographs at 20-megapixels (Phantom 4 Pro, 2017). DJI’s positioning of the camera below the body allows for unrestricted view of the subject and the gimbal allows to camera to shoot smooth and stable photos and video.

Figure 1. DJI Phantom 4 Pro image as http://store.dji.com/product/phantom-4-pro?site=brandsite

The impressive gimbal stabilized camera system of the drone is what makes it an ideal choice for commercial aerial photography and film making. Airworthiness, ease of operation, and relatively low acquisition cost all serve to solidify this choice. At a suggested retail price of $1499, the system is a reasonably priced and capable commercial sUAS (Phantom 4 Pro, 2017).

The next use examined is from the hobbyist side. Hobbyist unmanned aviation is more established than its commercial counterpart. The hobby stems from remote controlled aircraft of various types. A rapidly growing segment, however, is drone racing. With several classes and ability levels, selecting a suitable platform can also be difficult. Systems are very customizable and can be adjusted to suit the operators liking. Racing drones are small in comparison to most aerial photography sUAS and are purpose built to be fast and agile. Racers fly their multi-copter through a course of obstacles utilizing first-person view (FPV). Classes are based mainly on the size of battery cell used to power the aircraft, 250mW being the most common and a great place to start.

A lead hobby sUAS producer, Walkera, offers drone racing kits for every class of competition. Walkera offers several 250 class options with the Runner 250 PRO (see Figure 2) topping the list in ability. The quadrotor platform features a lightweight 464g aircraft (battery excluded) with a 143mm rotor diameter (Runner 250 Pro, 2017). The system uses quality electronic components and brushless motors. The integrated camera on the aircraft is high definition, 800 Television Lines (TVL) resolution sensor, optimized to transmit video at 5.8GHz (Runner 250 Pro, 2017). The forward and centerline placement of the camera allows for an unobstructed first-person view from the platform. The adjustable tilt allows for compensation for nose low attitudes required for high speed flight.

Figure 2. Walker Runner 250 PRO image as http://www.walkera.com/index.php/Goods/info/id/43.html

Light weight, solid build, good components, and a camera system designed for FPV use contribute to making the Runner 250 PRO a very viable FPV racing drone.

Both the sUAS mentioned are prime examples of how unmanned system designers tailor build these aircraft for their intended use. DJI designs drones to be employed as aerial cameras, while Walkera is focusing on the very unique need of hobbyist FPV racers. The applications for drones continue to grow, and the commercial drone market will most assuredly follow that trend.

References

Phantom 4 Pro. (2017). DJI. Retrieved from https://www.dji.com/phantom-4-pro

Runner 250 Pro. (2017). Walkera. Retrieved from http://www.walkera.com/index.php/Goods/info/id/43.html

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