Air/Water Drone Could Simplify Surveying
The geospatial community has been relatively quick to adopt unmanned aircraft systems (UAS). From September 2014 when the Federal Aviation Administration (FAA) began awarding exemptions to companies for the use of UAS until Jan. 20, 2016, 3,136 Section 333 exemptions had been approved, according to an AUVSI report. Of those exemptions, aerial photography, aerial inspection and aerial survey were listed in first, third and fourth place in application popularity. With new rules taking effect at the end of August 2016, the use of UAS is expected to increase even more.
Today, most imagine a drone as a multi-rotor or fixed-wing system that traverses air, but a new scheme is on the horizon that could completely change the definition of “drone” as we know it and expand geospatial capabilities even further.
Javier Diez, a professor in the Department of Mechanical and Aerospace Engineering at Rutgers University, is working on an unmanned system that he calls a dual platform system. It can operate as an aircraft and an underwater vessel. It can also seamlessly transition from air to underwater and underwater to air in less than a second.
“By the very nature of varied, differing environments, over time we have developed separate technologies and separate processes for gathering the respective layers of geospatial information,” says Keith Masback, CEO of the U.S. Geospatial Intelligence Foundation (USGIF). “We’ve not collectively done a very good job at characterizing the subsurface areas of the world’s oceans. Some estimates would put this at as low as 5 percent complete. So anything that could contribute in any way to beginning to chip away at that shocking lack of data would be quite helpful.”
The concept started as a student project in one of Diez’s classes four years ago and evolved into a more formal research project when he hopped onboard. When his team showed the first prototype to the U.S. Navy about a year and a half ago, Diez says they liked it right away and started funding it. They call it the Naviator project, for Navy and aviator.
While he is aware of other projects at other universities that involve things like deploying unmanned systems from underwater, he hasn’t heard of anything like the Naviator before.
“They’re able to do some of the components that we do, but to be able to show the full cycle, where you start in the air, you go underwater, then you go back to the air and you go back in continuously — we haven’t seen anybody doing that at this point. … It’s good in both mediums. It’s meant for both mediums.”
The fourth-generation system has a multi-rotor design and qualifies as a small UAS in terms of the FAA qualification of less than 55 pounds. It includes a total of eight propellers, each about 15 inches in length; four propellers at the top and four at the bottom. In the air, they move in the range of 10,000 rpm, whereas they move at a few hundred rpm underwater. Diez says the dual platform system requires propellers as opposed to fixed wings, but the size of the propellers and the speed at which they move are not the only factors to consider. Like with any other drone, specs have to be optimized for the weight of the vehicle. “It’s a combination of propeller, motor and speed control,” he says.
For now, the drone is operated manually and the controller directs the propellers to adjust from air to water or vice versa based on observation. In the future, sensors will help automate the transition and increase efficiency. Diez says they are playing around with an autonomous mode now, in which sensors are able to inform the top propellers, for example, that they have exited the water, entered the air and need to increase their rpm in order to elevate.
Battery life is also relative to the weight of the vehicle and medium. In air, the battery can last for around an hour, Diez says. Underwater, they’ve seen it last for up to a day, but if they stop using the motor and stay in one position, it can last much longer.
The catch is that it hasn’t been tested in a realistic environment yet. The only environment the Naviator has proved itself in is a pool that Diez says to be 5 meters deep at most. He says most of the components are designed to navigate up to 200 meters underwater, but they have yet to prove it. “In the air, it’s like any other multi-rotor.”
Right now, until it’s been tested outdoors, Diez says there is no real limitation as to the harshness of the environment or the distance from shore the system can withstand.
“I think it could be a big deal. … It’s like you have the capability to go from one environment to another with one piece of equipment. To me that’s really exciting.”
“We haven’t seen any reasons why we couldn’t go nearshore or deep-ocean. … Because we have such a smooth transition, we can operate in a very rough environment where you have big waves. I think that is going to be difficult for others to try to accomplish, how to survive in rough waves.”
He says its underwater capabilities introduce a whole new world to those familiar with multi-rotors in the traditional sense.
“When you see a vehicle react in air, it has to be very quick. In water you can do things like travel at 90 degrees. In air it would be impossible to travel at 90 degrees. So you can do very interesting things underwater. You can do acrobatics underwater; you can literally turn on your axis.”
Up until now, Diez says he has received feedback and interest from a number of deep ocean groups, including the oil and gas community, and the wind turbine community. He highlights the relevance of the system for bridges as well, pointing to the fact that all of the named infrastructure has a large presence underwater and above the surface, so a drone that works in both mediums could be useful for inspections.
The idea is brand new to Curtis Sumner, executive director of NSPS, who calls it an intriguing invention that could be beneficial to a lot of applications surveyors work with.
“I think it could be a big deal. … It’s like you have the capability to go from one environment to another with one piece of equipment. To me that’s really exciting,” he says. “Perhaps this could be a piece of equipment I could purchase that has that dual purpose, which would save me from having to buy two pieces of equipment, one of which would give me above-ground and above-water, and the other that would give me underwater capability. … In a general sense, a piece of equipment that allows you to do two of the things you need to do rather than one is obviously a good thing.”
Applying this technology to collecting data about littoral zones is what immediately comes to mind for Masback. He says those areas along the shorelines of oceans, seas, lakes and rivers are important to understand and have a tendency to change more rapidly over time than other areas.
“Understanding littoral zones is important for safety of navigation in support of tourism and trade, for emergency planning and preparedness, and for sustainability and conservation, among many other things,” he says. “An unmanned system which can operate seamlessly from air to water might facilitate more coherent data collection, which would provide better granularity and resolution. To be sure, it offers the potential to be more efficient.”
That said, Masback highlights that the unmanned system — the platform — is only one aspect of the potentially valuable geospatial tool. He says the remote sensing and broader geospatial intelligence capabilities are realized through the integration of sensors with that platform. So while having a system that can operate in the air and water creates opportunity to do things in ways we haven’t yet imagined in great detail, he says the sensor packages have to allow for taking advantage of that opportunity.
Right now, Diez and his research team have a lot more work to do. He says robustness is critical along with full autonomy and high endurance.
“You want to make a vehicle that is able to make decisions on its own. So that’s very, very far out — 10 years from now,” he says.
That isn’t to say that commercialization isn’t an end goal. Diez says he is looking for a big investment, already has good people on board, and is taking his time to go about the process the right way.
When Diez spoke with POB in May, the fourth generation Naviator was the latest to be revealed. He says a much bigger, fifth generation has been developed and is expected to make its debut on the National Geographic channel, probably later in the summer.
“The vehicle itself is not that expensive. It’s obviously your sensors [that add cost] and depends on what you want to carry. So it can probably be all the way from $10,000 (without sensors) to a few hundred thousand dollars depending on the sensors you want to carry.”
This is an incredibly exciting time in the GEOINT profession, Masback says. In fact, in light of such remarkable change in multiple technology areas, he says USGIF has identified that there is a synergy combining to create a GEOINT revolution. From Masback’s perspective, there are significant developments taking place on the platform side with unmanned systems, as well as the sensor side with miniaturization and the ability to get at multiple parts of the spectrum.
“Things like LiDAR mounted on unmanned systems are critically important for feeding the foundational underpinnings of both augmented and virtual reality efforts,” he says. “The ability to sense the world around us from multiple angles through multiple phenomenologies, with the associated compute power to seamlessly stitch it all together is a game changer. We will continue to see our surroundings sensed in higher and higher fidelity, and unmanned systems are absolutely part of that equation.”
Merced Irrigation District Employs Real-Time Hydrologic Operations Model
Dewberry reports it has been selected by California’s Merced Irrigation District (MID) to develop real-time hydrologic operations models using the U.S. Army Corps of Engineers Hydrologic Engineering Center’s (HEC) Real-Time Simulation (RTS) software, a public version of the Corps’ Water Management System Control and Visualization Interface.
MID owns several hydroelectric dams and reservoirs that support approximately 138,000 acres of irrigable land. Once fully implemented, the HEC-RTS model will improve the district’s ability to predict short-term and seasonal reservoir inflows due to precipitation and snowmelt. Various reservoir operation alternatives will be simulated using these inflows, balancing the need for water conservation and flood control, while increasing resilience during wet and dry years.
Dewberry will also develop a long-term planning model to support new and refined delivery strategies for the district. It will also use HEC-RTS to develop and integrate various models, including meteorological forecast data, hydrologic models (HEC-HMS), reservoir operation simulation models (HEC-ResSim), and hydraulic analysis (HEC-RAS).