Streamflow monitoring is a unique application of UAS. In many mountainous regions the water found in streams and creeks is a vital resource for farms where other sources of water is difficult to obtain. These lands rely on water from mountain sources to provide for agricultural needs as well as for human consumption. In the state of Colorado land owners have what are called water rights. These land owners who have water rights are entitled to a measured amount of water from naturally occurring sources such as rivers, streams, and creeks. To measure this flow, sensors are in place by the Colorado Division of Water Resources, however these sensors only monitor major waterways leaving land owners responsible for monitoring their own streams. This is typically accomplished with Parshall flumes – a device that is placed in the streamflow and can accurately measure the volume of water traveling through it (CSU, 2014). Often these water gauges are located in difficult to reach areas due to the natural terrain conditions of mountainous regions. This is where the use of UAS can be of benefit as it allows the land owners to monitor streamflow without having to travel along the difficult and often dangerous terrain. Additionally, the ability for UAS to operate with relatively low noise pollution gives UAS a much needed benefit in environments where domestic animals and wildlife reside. Three platforms that are ideally suited for streamflow monitoring are the DJI S900, the Lockheed Martin Indago, and the Aerovironment Qube UAS. As small VTOL UAS they are ideally suited for imaging tasks in mountainous regions.
DJI S900
The DJI S900 is a vertical takeoff and landing (VTOL) hexacopter. It is purpose built specifically for imaging payloads and is marketed towards photographers and videographers. However, because the target of streamflow monitoring is a visual gauge, the S900 is a capable platform for this task. Also because it is built with photography and videography in mind it is a very stable imaging platform. It is designed with arms eight degrees in inversion, and 3 degrees inclination (DJI, 2014) – creating a dihedral effect and making the platform more stable compared to a traditional helicopter configuration.
Lockheed Martin Indago
The Lockheed Martin Indago is a purpose built VTOL quadcopter. Designed with military and search and rescue in mind, the Indago is lightweight and portable yet rugged to meet professional applications. The entire system can be stored in a small briefcase, making this ideal for Water Resource personnel to travel with. Additionally, the ground control station (GCS) is weather resistant (Lockheed Martin, 2014) so as to maintain situational awareness even in poor environmental conditions, a benefit in mountain areas where weather is often unpredictable.
Aerovironment Qube
The Aerovironment Qube is also a quadcopter, and has been developed with search and rescue as its primary application. This makes it rugged and portable similar to the Lockheed Martin Indago. However, the Qube has a distinct commercial application advantage in the GCS – a system capable of being used on a touch-enabled tablet computer. This interface may prove to reduce the learning curve and attract a larger market of potential civilian operators.
Application Considerations
There are advantages to using small UAS (sUAS) for streamflow monitoring, such as portability, storage, and maneuverability. These are all needed elements in mountainous environments where the UAV may have to navigate small spaces, such as between trees, valleys, and boulders. Their agility is a benefit, however the drawback to these sUAS is flight time. By having to use small VTOL UAS, the battery life on these electric powered systems offers relatively little flight time, approximately 40 minutes for both the Indago and Qube, and 18 minutes for the S900. Additionally, there are legal barriers as directed by the Federal Aviation Administration (FAA) that limit UAS operation in the National Airspace System (NAS) to line of sight (LOS) only. Beyond line of sight (BLOS) is prohibited without authorization (FAA, 2014), this can be a challenge to operating in mountainous regions where there are many visual obstacles and hills to block view.
References:
DJI (2014). DJI Spreading Wings S900 (2014). Retrieved from:
http://www.dji.com/product/spreadingwings-s900/feature
Lockheed Martin (2014). Indago VTOL Quad Rotor (2014). Retrieved from:
http://www.lockheedmartin.com/us/products/procerus/quad-vtol.html
Aerovironment (2014). Qube UAS (2014). Retrieved from: https://www.avinc.com/public
safety/qube
Federal Aviation Administration (2014). Model Aircraft Operations Limits (2014). Retrieved
from: https://www.faa.gov/uas/publications/model_aircraft_operators/
Colorado State University (2014). Father of the Flume: Ralph Parshall (2013). Water Resources
Archive. Retrieved from: http://lib.colostate.edu/archives/water/parshall/flume.html
No comments:
Post a Comment