Samsung has a Roomba-like, autonomous cleaning robot called the Navibot, which the company markets outside the U.S.
It's already an ingenious and rather expensive household gadget, which is apparently seeing further improvement, that turns Samsung into front runner in the race for the most frivolous patent filing of 2013.
The patent application #20130000675 is titled "Robot cleaner and control method thereof". Samsung has a history of interesting robot patents, including devices that mimic human walking or breathing or ideas that put RoboCop into real life, so even a cleaning robot may include some interesting tech.
Samsung's Navibot, a $600+ cleaning robot is already a rather sophisticated device with a camera that video-records your home and determines the most efficient cleaning path as a result of it. A new patent filing indicates the Navibot will get even better: Instead of a traditional zig-zag pattern, the Navibot will now move in a curved zig-zag pattern, "thus decreasing the time required to clean an area during a change of the traveling direction of the robot cleaner." The idea: Because a traditional zig-zag pattern in lines requires the robot to start and stop periodically, the curved pattern is faster since there are no interruptions - which is apparently a clever improvement enough to justify a patent filing.
I have not had a chance to look at the Navibot myself and how well the robot cleans floors and whether the curved zig-zag provides any advantage over the Roomba, which moves in traditional zig-zag lines.