Roomba

Roomba is a series of autonomous robotic vacuum cleaners sold by iRobot.

Roomba was introduced in September 2002. As of February 2017^[update], more than 15 million units have been sold worldwide. Roomba features a set of basic sensors that enable it to perform its tasks. For instance, the Roomba is able to change direction upon encountering obstacles, to detect dirty spots on the floor, and to sense steep drops to keep it from falling down stairs. It uses two independently operating wheels that allow 360° turns in place. Additionally, it can adapt to perform other more creative tasks using an embedded computer in conjunction with the Roomba Open Interface.

All Roomba models are disc-shaped, 34 cm (13") in diameter and less than 9 cm (3.5") high. A large contact-sensing mechanical bumper is mounted on the front half of the unit, with an omnidirectional infrared sensor at its top front center. A recessed carrying handle is fitted on the top of most units.

As of 2016, there have been seven generations of Roomba units: the first-generation Original Series, the second-generation 400 & Discovery Series, the third-generation Professional & 500 Series, the fourth-generation 600 Series, the fifth-generation 700 Series, the sixth-generation 800 Series, and the seventh-generation 980 model. All models have a pair of brushes, rotating in opposite directions, to pick up debris from the floor. In most models, the brushes are followed by a squeegee vacuum, which directs the airflow through a narrow slit to increase its speed in order to collect fine dust. A horizontally mounted "side spinner" brush on the right side of the unit sweeps against walls to reach debris not accessible by the main brushes and vacuum. In the first generation of robots, the dirty air passes through the fan before reaching the filter, while later models use a fan-bypass vacuum.

The Roomba is powered by a removable NiMH battery, which must be recharged regularly from a wall power adapter. Newer second- and third-generation models have a self-charging homebase that the unit searches for at the end of a cleaning session via infrared beacons. Charging on the homebase takes about three hours. Four infrared "cliff sensors" on the bottom of the Roomba prevent it from falling off ledges such as stairways. Most second- and third-generation models have internal acoustic-based dirt sensors that allow them to detect particularly dirty spots and focus on those areas accordingly. Fourth-generation models have an optical sensor located in front of the vacuum bin allowing detection of wider and smaller messes. Many second- and third-generation Roombas come packaged with infrared remote controls, allowing a human operator to "drive" the robot to areas to be specially cleaned.

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Wikipedia