Field Test of the Puma™ AE (All Environment) Small Unmanned Aircraft System (UAS)
- Chad King
Monterey Bay National Marine Sanctuary
End Date: September 16, 2014
Traditional methods for marine mammal, seabird and turtle observations require qualified observers aboard ships or aircraft. These methods are cost-prohibitive for National Marine Sanctuaries to conduct at regular intervals. The Monterey Bay National Marine Sanctuary used a NOAA-owned Puma™ AE (All Environment) small unmanned aircraft system (UAS) to field-test its capability to detect various targets on the ocean’s surface, including marine mammals and other large marine organisms. The Puma UAS is a waterproof, all-electric propeller powered aircraft that is light enough to be launched by hand from small vessels, and includes a gimbaled camera payload that can swivel 360 degrees with zoom and infrared capabilities. Over two days, four flights totaling a length of 206.7 kilometers were made in northern Monterey Bay. Although primary targets (leatherback turtles and their jellyfish prey) were never observed, a total of eight Humpback whales (Megaptera novaeangliae) and one ocean sunfish (Mola mola) were recorded during six total hours of flight. The UAS proved adequate in detecting objects as small as one meter across from altitudes as low as 60 meters and large animals, such as whales at its maximum flight altitude of 300 meters. Although this system requires less personnel and costs significantly less than traditional observation methods, it lacks a high-definition camera, and may not yet be suited for rigorous data collection due to inability to calculate total area covered (i.e., target densities unobtainable). In its current configuration, this system may be better suited for reconnaissance applications within National Marine Sanctuaries, although future configurations of the UAS could remedy its current deficiencies.
- No trends to report in this pilot project.
DiscussionThe Puma UAS is primarily a reconnaissance tool for U.S. military applications. This particular system, now owned by NOAA, comes from the military and is optimized for scouting for targets and potential hazards in war zones. Along this same vein, this system could be optimal for scouting for illegal activity in the ocean such as illegal dumping, fishing in no-take marine protected areas, and even drug trafficking. This was the first time this system was applied to marine mammal observations within a National Marine Sanctuary, and furthermore, was the first time this system was used to run stratified “transects” to systematically cover an area with traditional field ecology methods.
Advantages to this system are its ability to be deployed with minimal crew and on small platforms such as the R4107 or even smaller vessels such as inflatables. The cost of an operational day is less than half of traditional plane-based marine mammal observation protocols. The ability for the drone to circle and further investigate targets at lower altitudes than manned aircraft may enhance identification of single targets over traditional methods.
Disadvantages to this system include the inability to calculate the width of a fixed camera view and thus densities of objects cannot be calculated, unlike traditional methods. Although a future version of this drone may include a high-definition camera, this current system is only capable of standard definition, making identification of some targets a challenge, especially over human eye-sight from a plane (enhanced with binoculars). Due to the limitations of the Puma UAS, it is less suited for rigorous data collection and is not comparable to traditional survey methods.
When considering cost per linear distance surveyed, the UAS comes out at about half the cost of the Twin Otter. On January 10, 2010, the Twin Otter flew to the Davidson Seamount and recorded 550 km of survey data. This represents a conservative estimate on what the twin otter can cover in a day, since the plane had to fly 70 nautical miles each way from Monterey Airport to the Davidson Seamount. Although the maximum field of view angle for the UAS is similar to that of an observer’s on the Twin Otter (15.75˚ to 12˚, respectively), the observer has a high confidence of a correct identification at the limits of their field of view. The edge of the drone’s maximum field of view is further distorted due to distance, and can be subject to sun angle, swell and wind chop that the camera’s sensor has a difficult time resolving without visual noise. These reasons presumably mean the Twin Otter covers significantly more area at a higher target identification confidence level than the drone. The Twin Otter has a reliably wide 2 kilometer observer footprint. In a real-world application, these costs may be closer when considering cost per unit area surveyed. Regarding application to National Marine Sanctuary interests, in its current configuration, the Puma UAS could be optimally used to detect illegal activity or perhaps for reconnaissance purposes such as finding an entangled whale that may have previously been reported by other transiting vessels. However, these applications would have to be conformed to current FAA regulations, as they limit the range of the drone to a 1.6 kilometer radius from the operational base or vessel. Future enhancements to the Puma UAS may include high-definition cameras and software that can calculate area covered. These hardware and software developments will greatly increase the drone’s application to more traditional and comparable quantitative survey methodology.
Study MethodsPersonnel for this project included two pilots from the Office of Marine and Aviation Operations (OMAO), an FAA-qualified observer, a vessel captain and mate, the principal investigator, and additional observers, if there was adequate room on the vessel. Field operations occurred on September 14 and 15, 2014, but were scrubbed on the planned third day (September 16) due to an oil leak on the Sanctuary vessel. The FAA cleared operations to occur anywhere within northern Monterey Bay and up to Point Año Nuevo. Operations never came within one mile of the shoreline.
The Puma UAS is an all-environment and fully waterproof aircraft system, has a wing span of 2.8 meters, a length of 1.4 meters, and weighs 6.1 kg. An enhanced precision navigation system with secondary GPS provides great positional accuracy and reliability. The Puma’s electric motor powers a propeller in the nose of the plane and was launched by hand by one of the pilots off the deck of the R4107. The Puma is capable of flying to an altitude of 10,000 feet and has a 15 kilometer range, but due to FAA regulations, it was limited to a 1,000 foot ceiling and a radius of 1.6 km around the vessel for the duration of this project. The drone flies at a speed between 20 to 45 knots (37 to 83 km/hr). The gimbaled camera is capable of 360 degree continuous pan, +10 to -90 tilt, and includes an infrared camera.
Flight was controlled via waypoints entered into a laptop computer operated by one of the pilots. During flight, the second pilot viewed live video in a shaded monitor and controlled the pan, tilt and zoom of the camera system. A 7-inch screen displayed live video to the principal investigator and observer(s).
A rigid transect method was not adhered to, as this was a pilot project. However, an attempt was made to run the R4107 in a predetermined heading within the operational area of northern Monterey Bay. After launch, the Puma would follow the R4107 and fly an alternating “snake” pattern that was roughly perpendicular to the bearing of the R4107. Each perpendicular segment ranged between 1 and 1.3 kilometers wide; never more than 0.7 kilometers from the vessel, well within FAA regulations.
When objects of interest were noted by the pilot or observer, the pilot controlling the video camera would attempt to zoom in on the object to attempt identification. If the object deserved further reconnaissance, the drone was programmed to circle the object. Identified targets were recorded onto a data sheet. To explore the camera’s capability of identifying objects at different altitudes, flight altitudes ranged between 60 and 300 meters, although the majority of time was spent near 60 meters. All video (standard definition) was recorded to a laptop hard drive and are available for future review. At the conclusion of the flight, the pilot gently landed the drone into the water, where it was retrieved from the back deck by the pilots.
Figures and Images
OMAO UAS pilot waiting to launch the PUMA drone on the back deck of the R4107
Upper left: Drone moments before "splash down;" gently landing in the water; Upper right: The moment of landing; Lower left: the drone is completely waterproof and buoyant; Lower right: An OMAO pilot retrieves the drone from the back deck of the R4107.
A humpack whale (Megaptera novaeangliae) as observed from the Puma UAS at an altitude of 271 feet (83 meters).
Map of all four tracklines flown and animal observations within the FAA-cleared operational area in northern Monterey Bay.