a system for the metering and delivery of small discrete volumes of liquid is comprised of a small or minimal number of inexpensive components . one such component is a movable member , such as a miniature precision reciprocating displacement pump head , which is driven by an actuator that comprises a shape memory alloy material . the operating mechanism of the system is of little or minimal complexity . the system facilitates the precise metering and delivery of the small discrete volumes of liquid . potential applications for the system include subcutaneous , long - term , automated drug delivery , for example , the delivery of insulin to a person with diabetes . in such an application , the small , simple and inexpensive nature of the invention would allow for its use as both a portable and a disposable system .