Patent Document ID: 5549152
Application ID: 08083589
Patent Flag: 1

Claim One:
1. A method for automatically modifying a linear contol algorithm which, in turn, controls a heating, ventilation and air conditioning (HVAC) system of a vehicle which discharges a flow of air to a passenger cabin of the vehicle, the algorithm having a target set point temperature and an offset and calibration coefficients, the system including a variable speed blower, means for varying air temperature, ducting, actuator having various control positions for contolling the direction of air flow and the ratio of fresh air to recirculating air and sensors for sensing temperature within the cabin, ambient temperature and the target set point temperature, the method comprising the steps of: sensing the ambient temperature; defining a first set of membership functions and fuzzy rules between the ambient temperature and target set point temperature to allow set point adjustment; modifying the target set point temperature based on the ambient temperature and the first set of membership functions and fuzzy rules; defining a second set of membership function and fuzzy rules between the ambient temperature and a first one of the calibration coefficients; modifying the first one of the calibration coefficients based on the ambient temperature and the second set of membership functions and fuzzy rules to allow calibration blending; defining a third set of membership functions and fuzzy rules between the ambient temperature and an offset; modifying the offset based on the ambient temperature and the third set of membership functions and fuzzy rules to allow non-linear offset compensation; and controlling the HVAC system based on the linear control algorithm having the modified target set point temperature, the modified offset and the modified first one of the calibration coefficients wherein one of the sensors sense sunload and wherein the method further comprises the steps of defining a fourth set of membership function and fuzzy rules between the sunload and the offset and modifying the offset based on the sunload and the fourth set of membership functions and fuzzy rules.