Abstract: A compact medical pump includes a linear peristaltic pumping mechanism driven by a motor located within a periphery of a belt of the pumping mechanism. The motor drives a gear set that drives a driving pulley which engages the belt having the rollers. A battery for the pump is positioned adjacent to the gear set. The pump includes a controller and user interface for operating the pumping mechanism as a function of pumping parameters input via the user interface. The controller may sense motor current and determine fluid path characteristics based on the sensed current.