Method and apparatus for controlling a medical fluid heater
AssigneeBaxter International Inc.
InventorsAlex Anping Yu, Peter Hopping
Life of this patent
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Abstract
A method, system and apparatus for performing peritoneal dialysis are provided. To this end, in part, a method of controlling a medical fluid heater is provided. The method includes the steps of determining a first heater control output based on a number of measured inputs for the heater and at least one mathematical relationship between at least two of the measured inputs, determining a second heater control output based on at least one fuzzy logic membership function and at least one fuzzy logic rule, and determining a third heater control output based on the first and second outputs and using the third heater control output to control the heater.
Claims21
A method of controlling a medical fluid heater comprising the steps of:
- determining a first heater control output based on a number of measured inputs for the heater and at least one mathematical relationship between at least two of the measured inputs;
- determining a second heater control output based on at least one fuzzy logic membership function and at least one fuzzy logic rule;
- and
- determining a third heater control output based on the first and second outputs and using the third heater control output to control the heater.
A method of controlling a medical fluid heater comprising the steps of:
- determining a first heater control output using a first mathematical relationship between a number of heater inputs and updating the first output at a first frequency;
- determining a second heater control output using a second mathematical relationship between a number of heater inputs and updating the second output at a second frequency, wherein the second mathematical relationship includes a measured fluid temperature feedback at the second frequency;
- and
- determining a third heater control output based on the first and second outputs and using the third heater control output to control the heater.
A method of controlling a medical fluid heater comprising the steps of:
- determining a first heater control output using a first mathematical relationship between a number of heater inputs;
- determining a second heater control output using a second mathematical relationship between a number of heater inputs;
- weighting the relative importance of the first and second outputs and determining a third heater control output based on the first output, second output and the weighting;
- and
- controlling the heater using the third heater control output.
A method of controlling a medical fluid heater comprising the steps of:
- determining a first heater duty cycle based on at least one input signal selected from the group consisting of:
- a measured number of pump stroke intervals, a heater input voltage and a measured fluid temperature;
- determining a second heater duty cycle by:
- (i) determining a plurality of fuzzy logic membership functions;
- (ii) converting a difference between a desired temperature and a measure temperature into fuzzy sets based on the membership functions;
- (iii) applying a plurality of fuzzy logic rules;
- and (iv) converting an output of the rules to the second duty cycle;
- and
- determining a third heater duty cycle based on the first and second heater duty cycles and using the third heater duty cycle to control the heater.
An automated dialysis system comprising:
- a pump operable to pump medical fluid;
- a heater operable to heat the medical fluid;
- and
- a controller that operates with the medical fluid heater to:
- determine a first heater control output based on a number of measured inputs for the heater and at least one mathematical relationship between at least two of the inputs;
- determine a second heater control output based on at least one fuzzy logic membership function and at least one fuzzy logic rule;
- and
- determine a third heater control output based on the first and second outputs and use the third heater control output to control the heater.
Dependencies are inferred from the claim text.