GLADIUS MINI – A Small Underwater Drone with Big Exploration Potential

When the Editor received the GLADIUS MINI underwater drone, we immediately ran a wonderfully absurd creative contest on our Facebook page, inviting everyone to dream up what this little yellow gadget could possibly be. Hilarious answers came flooding in like snowflakes — let's take a look at just how ridiculous the top five were:

1. A whale's colonoscope

2. An underwater extension cord and power strip

3. A wired remote tracker for walking your dog underwater

4. A micro-submarine you climb into and shrink down so you can perform surgery inside the human body

5. Earth Mother's dedicated semi-automatic exploratory levitating jet-propelled variable-frequency endoscope

What Is an Underwater Drone?

Although the answers in that absurd contest were genuinely creative, it wasn't hard to spot a common thread — the concept of exploration. Unmanned underwater vehicles (UUVs), also known as underwater drones, come in two main types depending on how they are operated. The first type are ROVs (remotely operated underwater vehicles), which use a fiber-optic tether and are controlled by an operator on the surface. The second type are AUVs (autonomous underwater vehicles), which operate without direct human control. ROVs are generally used for commercial purposes, while AUVs tend to be used for military or scientific applications. The GLADIUS MINI we tested trails a long tail behind it — so you already know it's an ROV!

The vast blue ocean has concealed countless secrets since time immemorial, waiting for humanity to uncover them. Yet physical constraints — the limits of human respiration and the pressures of the deep — have kept those secrets buried underwater for millennia. As technology advanced, the Titanic, which sank in the Atlantic in 1912, was discovered by Professor Robert Ballard using the Argo submersible. This opened the door for Canadian director James Cameron to capture precious footage of the wreck in 1995, ultimately giving birth to the blockbuster film Titanic in 1997.

Interweaving footage captured by submersibles with the memories of survivors, he constructed a story that recreated the scene of the sinking — putting humanity's values under pressure to the ultimate test.

The invention of unmanned drones, then, is rooted in that deeply human drive to explore the deep blue. CHASING has taken drone technology a step further, extending its reach from defense and scientific research into commercial and everyday applications, vastly expanding the possibilities for the future. Now let's unbox the CHASING GLADIUS MINI and see just how remarkable it really is!

Watch the Video Before You Read On!

The CHASING GLADIUS MINI package includes the drone unit itself, a relay unit (similar to a wireless transmitter, which broadcasts a Wi-Fi signal to interact with your smartphone acting as the controller), a handheld controller, and 50 m of fiber-optic cable. Assembly is straightforward — simply connect the drone and relay unit to the fiber-optic cable, and once powered on, the system starts up automatically.

Once everything is connected, the indicator lights on the relay unit show current battery level, Wi-Fi band (press the settings button to toggle between 2.4 G and 5 G), and ROV connection status. Next, grab your smartphone and connect it to the relay unit via Wi-Fi. After that, enable Bluetooth on your phone to pair it with the controller. Once that's done, the camera feed will appear on your phone screen!

As you can see in the screenshot above, the drone's control panel displays real-time depth, temperature, tilt angle, and heading — all extremely useful information for exploration. There are also a few standout features worth highlighting:

1. The controller allows you to adjust tilt angle upward or downward, enabling more versatile shooting angles. This is also handy for hull inspections, where a high upward tilt lets you observe the underside of a vessel — a genuinely practical feature.

2. Depth-hold mode and stabilization mode give you greater versatility during operation and help produce smoother, steadier footage.

3. Three speed settings — L, M, and H — make the low-speed mode particularly useful when you need stable, smooth shots.

4. The camera supports 4K video recording and includes built-in white balance control and color adjustment — a thoughtful touch for users who prefer not to do any post-processing.

GLADIUS MINI — Initial Test Summary

As a diver, the Editor initially wondered what practical use cases this little yellow minion could possibly have. But after the very first time taking it underwater and actually piloting it, I was struck by just what a mighty little beast it turned out to be. Here are a few application scenarios we brainstormed:

• Scouting unfamiliar dive sites or searching for objects: While a diver can of course strap on a scuba tank and jump in to survey the area in person, there are real constraints to consider — limited tank capacity on any given boat, no-decompression limits, depth limits (40 m for recreational scuba diving), and restricted dive time. An underwater drone capable of reaching 100 m and operating for up to 2 hours becomes the obvious choice in these situations.

• Hull inspection: Whether it's a commercial vessel or a fishing boat, any ship used over time will eventually need to be hauled out for hull inspection and barnacle removal. Traditionally, this meant relying on divers using scuba equipment to carry out the inspection — often in the murky, polluted water of a harbor, which poses its own risks including near-zero visibility and potential skin infections. A compact drone like this can step in and make hull inspection operations far safer and more convenient.

• Racing and recreational use: After giving it a quick spin, the use case that excited the Editor most was actually competitive recreation. The piloting experience is genuinely fun — you're not just managing direction but also depth, adding a whole extra dimension to the challenge. Perhaps the manufacturer could develop some organized exploration events in calm, enclosed water bodies in the future, letting children discover the ocean through play while weaving in ocean environmental education.

Areas We Hope to See Improved:

• Before a dive, the cable needs to be fed out; on return, it needs to be reeled back in. But the standard fiber-optic cable is a full 50 m long, making it very difficult for a single person to manage solo — you really need a dedicated line handler to pay out and retrieve the cable in sync. We've heard that the manufacturer is developing an automatic cable winding and unwinding device, so we're looking forward to seeing that.

• The relay unit is currently not waterproof, yet it's always being used right at the water's edge — a situation with a fairly high risk of getting wet. For now, you basically have to keep it hugged tightly to your body the whole time (laughs). We hope the manufacturer will consider adding waterproofing to the relay unit in a future version.

• The drone currently supports live underwater streaming, which is a very attractive feature for commercial events — think freediving competitions, for example. At the moment, however, it only supports live streaming to personal Facebook profiles. We hope that streaming to Facebook Pages will be enabled in a future update.

Related links:

• CHASING Official Website

• GLADIUS MINI Product Specifications

• Gear Maintenance Tips — TUSA BC Care