Each designer puts his own creativity on the project, maybe for a personal eureka moment or because of a specific customer request.

In this cleaning robot they added a little side brush to remove the dust on every corner of the floor usually difficult to clean.
Of course this tool requires its own dedicated motor and control circuits.

Another add-on is an UV lamp installed as an antibacterial tool. The ultraviolet light is supposed to sterilize the portion of the floor on which the robot travels.

To be powered up, the UV lamp requires higher voltage than the one available from the battery pack. For this reason a voltage booster circuit is installed very close to the lamp to minimize possible high voltage damages.