Two companies are working to change that by creating compact, affordable underwater robots.
The first is O-Robotix, the maker of Seadrone, which takes concepts from aerial drones and modifies them for use under water. The 10.5-by-12 inch Seadrone is compact enough to carry in your hand and has a gimbal-mounted HD camera that streams live video directly to a tablet. You can control the drone via the tablet interface or a joystick.
By design, Seadrone caters more to industrial customers. It's been used by acquafarmers and by oil and gas companies for inspecting underwater infrastructure. A collection of sensors measure pressure, temperature, water current and voltage. An auto depth and heading system, along with a 9-axis inertial measurement unit (IMU), make it easier to steer, allowing users to focus on other tasks.
It comes in three models depending on the number of thrusters, which affects speed and maneuverability:
The second company hoping to make a splash underwater is OpenROV. Unlike Seadrone, its v2.8 robot is geared more towards enthusiasts. It's priced at $899 and comes as a DIY kit. It doesn't have all the sensors that the Seadrone has, but the v2.8 can be modified because the company has made the design open source. Like Seadrone, the v2.8 can be operated with a joystick.
OpenROV expects to release its next underwater drone, Trident, in November. It will cost around $1,500 and come ready-assembled. The Trident will be faster than its predecessor, but also more maneuverable in tight spaces.
The drones are available for purchase online.