Infusion pump assembly

A wearable infusion pump assembly comprising:

• a reservoir for receiving an infusible fluid;
• an external infusion set configured to deliver the infusible fluid to a user;
• and
• a fluid delivery system configured to deliver the infusible fluid from the reservoir to the external infusion set, wherein the fluid delivery system includes:
• a volume sensor assembly;
• a pump assembly for extracting a quantity of infusible fluid from the reservoir and providing the quantity of infusible fluid to the volume sensor assembly, wherein the volume sensor assembly is configured to determine the volume of at least a portion of the quantity of fluid;
• a first valve assembly configured to selectively isolate the pump assembly from the reservoir;
• a second valve assembly configured to selectively isolate the volume sensor assembly from the external infusion set;
• a bracket assembly configured to maintain the second valve assembly in an activated state;
• and
• a bracket actuator configured to actuate the bracket assembly to maintain the second valve assembly in the activated state;
• wherein the bracket actuator includes a shape memory actuator.