Water trailing detection system

1. A floor cleaning machine comprising:

a chassis configured to move along a cleaning path;

a cleaning mechanism connected to the chassis to perform a cleaning operation;

a liquid system connected to the chassis to provide liquid to the cleaning mechanism;

a recovery system connected to the chassis to recover liquid from the cleaning operation;

a control system connected to the floor cleaning machine to control performance of the cleaning operation; and

a cleaning operation sensing system connected to the control system and including a moisture sensor configured to detect moisture from the cleaning operation, the moisture sensor comprising a first conductive bristle defining a first electrode that is spaced from a second conductive bristle defining a second electrode, wherein the first and second electrodes are disposed in close proximity to the cleaning path and are configured to sense the liquid from the cleaning operation external to the floor cleaning machine.

2. The floor cleaning machine of claim 1 , wherein the first and second electrodes are mounted to the frame to extend lengthwise across at least a portion of the cleaning path.

3. The floor cleaning machine of claim 1 , wherein the first electrode and the second electrode are connected to a mounting system that is adjustable to raise and lower the first electrode and the second electrode.

4. The floor cleaning machine of claim 1 , wherein:

the first conductive bristle is part of a first cluster of bristles; and

the second conductive bristle is part of a second cluster of bristles spaced from the first cluster of bristles.

5. The floor cleaning machine of claim 4 , wherein the recovery system further comprises a squeegee blade and the first and second clusters of bristles are positioned on a trailing side of the squeegee blade.

6. The floor cleaning machine of claim 1 , further comprising an absorbent pad connected to the chassis to contact the cleaning path and absorb moisture, wherein the recovery system further comprises a suction motor and the cleaning operation sensing system comprises a current sensor configured to sense current flow through the suction motor.

7. The floor cleaning machine of claim 1 , wherein the recovery system further comprises a suction motor and the cleaning operation sensing system comprises a pressure sensor configured to sense suction generated by the suction motor.

8. The floor cleaning machine of claim 1 , wherein the recovery system further comprises a squeegee blade and the cleaning operation sensing system comprises a sound sensor connected to the chassis proximate the blade.

9. The floor cleaning machine of claim 1 , wherein the cleaning operation sensing system comprises a camera connected to the floor cleaning machine and configured to view the cleaning path behind the recovery system.

10. The floor cleaning machine of claim 9 , wherein the camera comprises a thermal imaging camera.

11. The floor cleaning machine of claim 9 , wherein the liquid system includes a liquid cleaning solution and a tracing element added to the liquid cleaning solution visible by the camera.

12. A moisture detection system for a floor cleaning machine configured to drive along a cleaning path, the moisture detection system comprising:

a frame for connecting to a cleaning machine;

electrodes connected to the frame for engaging moisture along the cleaning path; and

a sensor electronics system connected to the electrodes to determine presence of moisture at the electrodes;

wherein the electrodes comprise a plurality of bristles extending from the frame, and wherein the sensor electronics system is configured to detect conductivity between sections of the plurality of bristles.

13. A floor cleaning machine comprising:

a chassis having a forward end and an aft end, the chassis configured to move along a cleaning path;

a cleaning mechanism connected to the chassis to perform a cleaning operation;

a liquid system connected to the chassis to provide liquid to the cleaning mechanism;

a recovery system connected to the chassis aft of the cleaning mechanism to recover liquid from the cleaning operation;

a control system connected to the floor cleaning machine to control performance of the cleaning operation; and

a water trailing detection system comprising:

a frame connected to the chassis aft of the recovery system;

an absorbent medium connected to the frame; and

a moisture sensor in communication with the control system and configured to generate a signal in response to moisture in the absorbent medium.

14. The floor cleaning machine of claim 13 , wherein the control system is configured to control autonomous movement of the chassis and autonomous performance of the cleaning operation, wherein the control system can adjust one or both of the autonomous movement of the chassis and the autonomous performance of the cleaning operation in response to receiving the signal.

15. The floor cleaning machine of claim 13 , wherein the moisture sensor comprises:

a first electrode extending across a first portion of a length of the cleaning path; and

a second electrode extending across a second portion of the length of the cleaning path; the second electrode spaced aft of the first electrode on the frame adjacent the absorbent medium.

16. A floor cleaning machine comprising:

a chassis configured to move along a cleaning path;

a cleaning mechanism connected to the chassis to perform a cleaning operation;

a liquid system connected to the chassis to provide liquid to the cleaning mechanism;

a recovery system connected to the chassis to recover liquid from the cleaning operation;

a control system connected to the floor cleaning machine to control performance of the cleaning operation; and

a cleaning operation sensing system connected to the control system and including a moisture sensor configured to detect moisture from the cleaning operation, the moisture sensor comprising a first electrode and a second electrode spaced from the first electrode, the first and second electrodes disposed in close proximity to the cleaning path and configured to sense the liquid from the cleaning operation external to the floor cleaning machine, wherein the cleaning operation sensing system further includes a trailing mop system mounted to the floor cleaning machine along the cleaning path at a rear of the floor cleaning machine, and wherein the moisture sensor is mounted to the trailing mop system.

17. The floor cleaning machine of claim 16 , wherein the trailing mop system comprises:

a frame connected to the chassis; and

an absorbent medium mounted to the frame to contact the first electrode and the second electrode and positioned to contact the cleaning path and absorb moisture.