Abstract: An autonomous floor cleaning robot includes 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 cleaning robot; and a pad sensor arranged to sense a feature of a cleaning pad held by the pad holder and generate a corresponding signal. The controller is responsive to the 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 signal generated by the pad sensor.

Abstract: A method of bulk transport of proppant is disclosed comprising: transporting proppant in an intermodal transport container to a well site, the intermodal transport container having four vertical walls, a roof, and a base, defining an enclosed interior, the proppant being loosely disposed within the enclosed interior; and unloading at least a portion of the proppant through one or more gates in the intermodal transport container at the well site. An apparatus for bulk transport of proppant is also disclosed.