Support surface overlay with acoustic patient detection

A support surface overlay system comprising:

• a bladder having a first selectively inflatable compartment and a first fluid conduit in fluid communication with the first selectively inflatable compartment;
• and
• a control system configured to selectively inflate and deflate the bladder and to detect a presence of a load on the bladder, the control system comprising:
• a controller having a pump configured to selectively inflate and deflate the first selectively inflatable compartment and a pump outlet conduit in fluid communication with the pump;
• a memory configured to store predetermined data indicative of a first operating parameter related to inflation and deflation of the first selectively inflatable compartment with the bladder in an unloaded state as a function of time;
• a first sensor configured to detect and provide data signals indicative of the first operating parameter related to inflation and deflation of the first selectively inflatable compartment as a function of time;
• and
• a processor configured to receive the data signals from the first sensor, compare the data signals received from the first sensor to the predetermined data stored in the memory according to a predetermined criteria, and determine whether or not a load is present on the bladder based on the comparison;
• wherein the first operating parameter comprises sound in, on, or near one of the first fluid conduit and the pump outlet conduit as a function of time;
• wherein the predetermined data stored in the memory is indicative of an unloaded-state profile of the sound in, on, or near the one of the first fluid conduit and the pump outlet conduit as a function of time;
• and
• wherein the first sensor comprises a first acoustic sensor physically associated with the one of the first fluid conduit and the pump outlet conduit by being disposed within the one of the first fluid conduit and the pump outlet conduit, attached to an exterior surface of the one of the first fluid conduit and the pump outlet conduit, or separated therefrom while configured to detect the sound in, on, or near the one of the first fluid conduit and the pump outlet conduit.