The sensor cluster was a large, circular array of sensors.
Such an array was located above the primary biobed in some Starfleet sickbays. This unit contained a number of sophisticated biosensors, and could also project a force field for restraining patients or maintaining a sterile environment. (TNG: "Man Of The People"; Star Trek: The Next Generation Technical Manual)
The sensor cluster set piece was originated on the USS Enterprise-D in Star Trek: The Next Generation. It was also part of the USS Voyager sickbay as well as that of Enterprise NX-01.