Mankind is a curious species by nature, using technology to push the boundaries of what we can achieve and the places we can go. There’s an innate need for people to discover unknown lands, experience flight, and explore the depths of the sea. With the PowerVision PowerRay underwater drone, even the average person can experience the mysterious world that lies beneath the surface like never before.
While most people by now are probably familiar to some extend with aerial drones, the concept of consumer underwater drones is relatively foreign. Sure, we’ve all seen the scientific expeditions on the nature channels where they take a massive underwater robotic submarine out to some tropical island to search for a sunken ship or Atlantis, but that is far from attainable or practical for the rest of us.
The folks at PowerVision actually have a couple aerial drones (PowerEgg and PowerEye) in their lineup in addition to another underwater drone (PowerDolphin) to accompany the PowerRay, and they all pretty unique in their own right. This being the first submarine drone I have gotten my hands on, I was coming to the scene with fresh eyes.
Building an Underwater Drone
Designing an underwater drone is inherently more complicated than one for the sky, as factors like waterproofing, pressure, signal interference, and a variety of other challenges present themselves. Right off the bat, the PowerRay visually looks to have tackled those challenges gracefully, with a sleek and low-profile design.
Unlike the traditional tubular image that comes to mind when thinking of a submarine, the PowerRay is a relatively flat and extremely streamlined, with flowing lines that looks like every curve was meticulously weighed for hydrodynamic efficiency.
The watercraft is 18” x 11” x 5” and weighs eight pounds, which sounds like a lot (and it is; the Inspire 2 from DJI is 7.58lbs), but considering the submersible doesn’t need to deal with pesky gravity, the weight isn’t a negative factor. Not to mention the PowerRay Wizard comes in a nice, combination locked, Styrofoam-lined rolling luggage case to store all the components and make for easy transportation, which is convenient for travel and nice considering the $1,888 price tag (there is a PowerRay Explorer at $1,488 and PowerRay Angler for $1,799 with variations in the kit).
Directly on the nose of the craft is the camera lens, which is flanked to either side by a dimmable 450-Lumen (6500K temperature) LED which helps to illuminate the water directly in front of the submarine for video capture and navigation via 720p or 1080p live video feed. Unlike aerial drones, the PowerRay is (of course) completely sealed so no external memory cards are used to store video or photo captured during a dive and instead transmitted via the app.
Also worth noting that many aerial drones use strictly 720p liveview, however the higher resolution option is pretty neat here.
Underwater Drone Propulsion
The PowerRay uses dual side-mounted motors for forward and reverse thrust, along with one centrally-mounted rotor to control depth, which maxes out at 98’. Those two rotors, despite being only about 3” across push the submarine to 3.4mph (3Kn to be specific) in still water. While that may sound pretty unimpressive to most drone pilots, there is a considerable amount more drag in water than air and there are always currents to factor in.
At light use the PowerRay can last four hours on a full charge, which is really impressive and far beyond anything an aerial drone can achieve. In all the drones I’ve seen so far, the max flight time is 30 minutes (Mavic Pro Platinum), so this is leaps and bounds above the lifespan of airborne drone batteries.
With consistent cruising and maneuvering in “L speed”, the 6400mAh LiPo battery life drops to 1.5 hours, which is by no means a slouch, and at “H speed mode” racing the battery life is cut down to 30 minutes. Considering the main purpose of this underwater drone leans more towards exploration (or fishing even), it is more likely that the drone would be in a cruising mode.
Piloting a Submarine Drone
Since wireless signal doesn’t penetrate water well, the PowerRay relies on a 210’ cable to deliver commands and relay the video feed back to the captain. That cable is a 4.2mm-thick textured hard rubber, which feels quite durable. The setup is pretty interesting actually, and the cable tethers the drone into their Base Station, which is a 2.4GHz wireless hub that communicates with the remote and PowerVision app.
The hub, drone, and remote all have internal batteries that can be charged simultaneously via a wall charger with ports for all three, which is nice to not have to worry about several sets of cables getting misplaced.
The remote and interface are quite similar to those from DJI, so anyone familiar with that will quickly catch on to the PowerVision functions, and even for those new to drones it is pretty self-explanatory.
Underwater Drone with a Camera
Underwater photography can be a bit more tricky than above the surface, as there are variables that interfere with visibility like shadows, water clarity, and limitations to the distance that can be seen. That being said, PowerVision made the right move with their camera and opted for a 1/2.3” CMOS sensor, with 12MP stills and 4K video that has a 95° field of view at f/2.8. The 4K video shoots at 25fps, while offering 2.7K at 50fps and 1080p at 60fps.
For still photos, the PowerRay has burst shots in 1/3/5 frame settings, and an adjustable ISO for those who want to switch off Auto. The camera was quite good, and no fisheye distortion so everything in the camera view was clear and proportionate.
Even when in the more speedy modes, there didn’t seem to be any blur or distortion of the feed and the 4K quality looks fantastic in the right settings. Full transparency, I made the poor choice to test the PowerRay in a local park reservoir and visibility was absolutely horrible, so I defer to some beautiful shots from Isla de las Mujeres from JerryRigEverything to show the true video capability of a quality underwater drone with a camera.
What Else Can an Underwater Drone Do?
I’ve scoured the web and have not found any other submarine drone anywhere near the capabilities and price of the PowerRay, so this might be my one and only experience diving to the depths for a while. I’ll admit when I first had this thing in my hands although it looked beautiful, I couldn’t imagine myself trekking out to a lake or ocean regularly to explore underwater.
Of course that is coming from an aerial drone mindset, where I can literally liftoff in my backyard if I want to scratch the drone itch, but need to drive a little ways to find some water (even farther for clear water). After playing with the PowerRay though, they have built in some really slick features that make me think I could see myself having one of these. Being able to cruise around for hours is something consumer aerial drone technology is years away from, and it is a very different form of enjoyment.
Beyond taking 4K video and 12MP photos, PowerRay has a few features that make it awesome for fishermen, giving them the ability to not only see under the surface visually but actually locate fish and bring the bait right to them.
Fishing with a Drone
That’s right, PowerVision has a model of their sub that is a drone fisherman, equipped with a baseball-sized sphere that acts as a fish finder both on and off the watercraft. When used with the PowerRay, the little thing tucks right up under the “chin” of the unit and hangs down kind of like a gunner turret on a WWII bomber.
This device tracks below the unit at a 30° angle and uses sonar to map out the ocean (or lake) beneath the drone for up to a depth of 131.2’. Considering the drone itself can dive 98’, by my calculation that gives captains a total ocean depth coverage of 229’ for fish, which is pretty incredible.
The Fishfinder device readings are delivered right to the app, where users can see the imagery of the ocean floor and fish as the PowerRay cruises over them. What’s also great about this module is that it can be removed and used as a standalone fish finder, by just tossing it into the water and letting it float along. To my knowledge there isn’t a tracking beacon that locates the device, so it shouldn’t be let to float away from eyesight.
If that isn’t enough to get a leg up on the fish, the PowerRay also has a remote-operated bait drop at the bow on the hull of the craft, which can support up to 4oz. Basically, a little actuator opens to allow a fishing line to be strung through, and closed so it holds in-place during travel.
I’ve seen people use aerial drones to fly a line out over the water and drop it, but never something as advanced as using an underwater drone for fishing and being able to target them directly. I generally enjoy fishing the old-fashioned way, but I can’t ignore the awesome factor that this tech instills, and makes it an actual useful product outside the underwater videography and recreational space.
What is it Like to Captain an Underwater Drone?
There are a few things that I ran across when taking the PowerRay down below that didn’t really come up in above-water drone use. First off, the critical tether that runs video, photo, and power commands from the Base Station to the submarine can get tangled and create a mess. When it comes out of the package, it’s a nice and neat tight coil that I promptly got tied into a rat’s nest knot.
In future use, I would take the time to wrap the cable around a makeshift spool, so it could be let out and reeled in neatly to avoid any problems when attempting to sail. This isn’t a problem with PowerVision, it is just something that never comes up with drones the sky.
Another thing to consider is the surroundings. While any drone use requires consideration of the surroundings and safe operation, an underwater drone doesn’t have as much danger of crashing so much as there is danger of getting the cable tangled underwater. If pilots are diving in an area popular for activity, there is a possibility the cable could get impacted by boaters or submerged objects.
I myself experienced the impact of submerged algae on the PowerRay dive, and aside from ruining the visibility it actually clogged the vertical propeller and halted the expedition. The instructions clearly state not to run through fine waterweed, but it did sneak up on me and accumulate in the propeller housing, which required retrieval of the unit and attention to clear it out before re-engaging.
That being said, while a park lake isn’t the best venue to do underwater exploration, the far better location would be in an ocean where there is more to see and less to get in the way.
Another interesting element is the complete lack of line of sight when captaining the submarine, until the craft gets close to and disturbs the surface. The video feed does a great job of communicating what is directly ahead, however there isn’t a directional compass in the app that helps triangulate the position of the drone when it is submerged. This could be helpful, as once it goes underwater all sense of direction is lost.
Why This is the Best Underwater Drone
The PowerRay is an awesome device, and I couldn’t have been happier to get a break in the scene for something like this. Amongst the legitimate aerial drones the market is flooded with “me too” quads, all trying to knock off one another (or just DJI) and putting out mediocre product. The underwater drone field is wide open, and PowerVision knocked it out of the park.
Having a four hour battery life is ridiculous, and ensures far more time out having fun than the nearest consumer aerial drone by leaps and bounds. The interface is familiar and useful, while simple enough for newbies to be comfortable with.
The PowerRay comes in three kits to make it even more tailored for the pilot’s use case. The PowerRay Explorer is the ground floor, and has the basics to dip a toe into the underwater exploration. Stepping up there is the PowerRay Angler, which has all the cool fishing goodies, and probably the best package. The PowerRay Wizard has all of the above, including a Zeiss VR google so users can go full FPV during their dives.
4K video, 12MP stills, and 1080p live view make this an incredibly capable photography tool, and for those who spend considerable time on the water it can be a fantastic tag along device to explore more. With a diverse functionality to include advanced fishing tactics and multi-purpose features, this is the best underwater drone that exists or will exist until something can do it without a tether. Until then, the PowerRay is a very impressive underwater exploration device that has no equal.