AV NEWS: Tethered Drones

For most consumer drones on the market today, the biggest limitation is flight time. Battery technology hasn’t gotten to the point where UAVs are able to fly for more than 30 minutes or so per battery. That’s where companies like CyPhy, BFD Systems and others hope to offer an alternative solution. Those were just a few companies at this year’s AUVSI Xponential conference to showcase their tethered drone systems. Tethered drones still must comply with all FAA regulations for unmanned aircraft. One of the biggest advantages to a tethered system, though, is longer flight times. In some cases, they can stay in the air for days on end. “The tethered drone is counterintuitive in some cases because you lose a little bit of flexibility in being able to fly around. But what you lose in that flexibility, you gain in persistence, ease of use, simplicity to set up. So we can fly this drone for days or weeks at a time, not just 20, 30 minutes.” While it’s true that the flight capabilities of a tethered drone are limited, the tethered systems still make a lot of sense for many uses. That includes security at large events like the Boston Marathon, where drones from the Danvers, Massachusetts-based CyPhy have flown for the last two years. With a power supply allowing the drone to fly for long periods of time, CyPhy’s drone was able to provide a constant video feed back to a ground station, where security could monitor the feed. “We were approached by the authorities up there to fly at a couple different locations. So we flew in 2017 for the first time at two locations. Beautiful day. Provided our video feed straight into the command center. It was great. 2018, the weather was terrible. We had three different sites that we flew, and despite the bad weather, we were able to fly despite some of the other assets not being able to fly.” Philadelphia-based BFD Systems, specializes in building custom drones capable of carrying heavy payloads. It wasn’t until the last year or so, though, that a tethered drone was added to BFD’s fleet. Similar to the CyPhy tethered drone, BFD’s aircraft has a number of different applications. Their tethered system can lift a payload of up to 26 pounds and can carry multiple cameras and antennas. “This has been deployed to disaster areas such as Puerto Rico and other places around the country. What it is is it supplies electricity up to the drone. There’s a lot of tether systems that are around and you can check out and are great for a lot of different applications. What makes this unique is that it’s 5,000 watts and it has two fiber cables for data. So it will send 20 gigs of data up and down the tethers.” Tubman says everything about their tethered aircraft has redundancies, including the motors and the power supply. For example, if something were to happen to the tethered power cord, backup batteries on the drone would kick in. Tubman noted that BFD has also been working with partners in the broadcasting world to use their tethered drone on TV. While it’s not an ideal aircraft for everybody, he believes the UAV industry will continue to embrace tethered drones. “I think that tethered systems and hybrid electric systems are definitely going to be becoming more popular. Everyone always kind of wants these things to fly for longer. It’s a multirotor. Motor aircrafts are limited by what the batteries can deliver as far as power density. If you don’t need to be going far away, if you want to operate within 100-foot radius, then a tethered solution could be really good for you.” For more stories about the people, technology, and updates shaping the drone industry, follow this link - www.airvuz.com/user/airvūznews.