Abstract: The concentration of air or other agents in a fluid delivery line is determined by monitoring agent signals and processing those agent signals along with information regarding the age of each agent signal. The processor determines a primary agent concentration value based on the received agent signal values, with the primary agent concentration value determined by giving greater weight to more recent agent signal values. Where the primary agent concentration value exceeds a primary threshold value, an alarm signal may be activated. The processor also may determine a secondary agent concentration value, which may be determined from the actual agent signal values instead of the weighted agent signal values. Where the secondary agent concentration value exceeds a secondary threshold value, an alarm signal may be activated.

Abstract: The concentration of air or other agents in a fluid delivery line is determined by monitoring agent signals and processing those agent signals along with information regarding the age of each agent signal. The processor determines a primary agent concentration value based on the received agent signal values, with the primary agent concentration value determined by giving greater weight to more recent agent signal values. Where the primary agent concentration value exceeds a primary threshold value, an alarm signal may be activated. The processor also may determine a secondary agent concentration value, which may be determined from the actual agent signal values instead of the weighted agent signal values. Where the secondary agent concentration value exceeds a secondary threshold value, an alarm signal may be activated.

Abstract: The concentration of air in a fluid delivery line is determined by monitoring output signals corresponding to the amount of air detected in the fluid and processing those signals along with information as to the time or total volume of fluid dispensed since each signal was produced. The processor determines an air concentration value based on the received signal values, with the air concentration value determined by giving greater weight to more recent signal values. Where the air concentration value exceeds a predetermined value, an alarm signal may be activated or fluid delivery may be stopped. The processor also may determine a secondary air concentration value, which may be determined from the raw signal values instead of the weighted signal values. Where the secondary air concentration value exceeds a second predetermined threshold, an alarm signal may be activated or fluid delivery may be stopped.

Abstract: The concentration of air or other agents in a fluid delivery line is determined by monitoring agent signals and processing those agent signals along with information regarding the age of each agent signal. The processor determines a primary agent concentration value based on the received agent signal values, with the primary agent concentration value determined by giving greater weight to more recent agent signal values. Where the primary agent concentration value exceeds a primary threshold value, an alarm signal may be activated. The processor also may determine a secondary agent concentration value, which may be determined from the actual agent signal values instead of the weighted agent signal values. Where the secondary agent concentration value exceeds a secondary threshold value, an alarm signal may be activated.

Abstract: Flow parameters in a fluid delivery assembly are determined by monitoring pressure responses and processing those responses along with information regarding the fluid flow. In one aspect, a processor controls the pump to pump flow quantities in accordance with a pseudorandom code. Portions of the resulting pressure signal sensed at the conduit is averaged, and the averaged values are then decoded in accordance with the pseudorandom code. An estimate of the equilibrium pressure is generated from the decoded average pressure values, while a summation of the pressure samples is generated from the undecoded pressure signals. The resistance to fluid flow of the system is determined from the estimated equilibrium pressure and pressure summation. For low flow rates, a processor controls the pump to pump fluid in a series of fluid boluses, with each fluid bolus delivered in the beginning of a separate timeslot.

Abstract: Flow parameters in a fluid delivery assembly are determined by monitoring pressure responses and processing those responses along with information regarding the fluid flow. In one aspect, a processor controls the pump to pump flow quantities in accordance with a pseudorandom code. Portions of the resulting pressure signal sensed at the conduit is averaged, and the averaged values are then decoded in accordance with the pseudorandom code. An estimate of the equilibrium pressure is generated from the decoded average pressure values, while a summation of the pressure samples is generated from the undecoded pressure signals. The resistance to fluid flow of the system is determined from the estimated equilibrium pressure and pressure summation. For low flow rates, a processor controls the pump to pump fluid in a series of fluid boluses, with each fluid bolus delivered in the beginning of a separate timeslot.