Here is a robot that transforms from a submarine into a half-humanoid with two arms to take on tasks under water. The Aquanaut by Houston Mechatronics has sensors to gather data. In submarine mode, it cruises long distances to get to its destination.
Once the robot starts transforming, its head, carrying stereo cameras, a 3D sensor, and a sonar system, rotates into place. Its arms are equipped with force sensors and clawLIKE grippers.