Autonomous floor cleaning with a removable pad

1. An autonomous floor cleaning robot, comprising:

a robot body defining a forward drive direction;

a controller supported by the robot body;

a drive supporting the robot body and configured to maneuver the robot across a surface in response to commands from the controller;

a pad holder disposed on an underside of the robot body and configured to retain a removable cleaning pad during operation of the robot; and

a pad sensor arranged to sense a feature of the cleaning pad held by the pad holder and generate a corresponding signal;

wherein the controller is responsive to the corresponding signal generated by the pad sensor, and configured to control the robot according to a cleaning mode selected from a set of multiple robot cleaning modes as a function of the corresponding signal generated by the pad sensor.

2. The robot of claim 1 , wherein the pad sensor comprises at least one of a radiation emitter and a radiation detector.

3. The robot of claim 2 , wherein the radiation detector exhibits a peak spectral response in a visible light range.

4. The robot of claim 1 , wherein the feature is a colored ink disposed on a surface of the cleaning pad, the pad sensor is configured to sense a spectral response of the feature, the corresponding signal being indicative of the sensed spectral response.

5. The robot of claim 4 , wherein the controller is configured to select the cleaning mode by comparing the sensed spectral response to a stored spectral response in an index of colored inks stored on a memory storage element operable with the controller.

6. The robot of claim 4 , wherein the pad sensor comprises a radiation detector having first and second channels responsive to radiation, the first channel and the second channel each configured to sense a portion of the spectral response of the feature.

7. The robot of claim 6 , wherein the first channel exhibits a peak spectral response in a visible light range.

8. The robot of claim 6 , wherein the pad sensor comprises a third channel that senses another portion of the spectral response of the feature.

9. The robot of claim 6 , wherein the first channel exhibits a peak spectral response in an infrared range.

10. The robot of claim 4 , wherein the pad sensor comprises a radiation emitter configured to emit a first radiation and a second radiation, and the pad sensor is configured to sense a reflection of the first and the second radiations off of the feature to sense the spectral response of the feature.

11. The robot of claim 10 , wherein the radiation emitter is configured to emit a third radiation, and the pad sensor is configured to sense the reflection of the third radiation off of the feature to sense the spectral response of the feature.

12. The robot of claim 1 , wherein the feature comprises a plurality of identification elements, each identification element having a first region and a second region, and wherein the pad sensor is arranged to independently sense a first reflectivity of the first region and a second reflectivity of the second region.

13. The robot of claim 12 , wherein the pad sensor comprises:

a first radiation emitter arranged to illuminate the first region,

a second radiation emitter arranged to illuminate the second region, and

a photodetector arranged to receive reflected radiation from the first region and reflected radiation from the second region.

14. The robot of claim 12 , wherein the first reflectivity is substantially greater than the second reflectivity.

15. The robot of claim 1 , wherein the multiple robot cleaning modes each defines a spraying schedule and navigational behavior.