Patent ID: 7727181

Claim:
A method, comprising: providing a disposable component comprising a pump element; providing a durable component comprising a microprocessor and a shape memory element, the disposable component configured to mate and operate with the durable component; when the disposable component is mated with the durable component, initiating the flow of a liquid through a portion of the disposable component with a known volume using, at least in part, the shape memory element, wherein the shape memory element is operatively coupled to the pump element and is configured to move the pump element from a first position to a second position to initiate flow of the liquid; determining the time to pump the liquid through the known volume of the portion of the disposable component using, at least in part, a plurality of sensors, wherein each of the plurality of sensors have a plurality of electrodes configured to detect an interruption of a flow stream of the liquid through the known volume portion of the disposable component; and determining the volume of a dose based at least in part on the determined time to pump the known volume.