| 摘要 |
First and second variable quantities, e.g. pressure and temperature of an aircraft tyre, where the value of the first variable quantity is affected by changes in the value of the second variable quantity, are measured by a system including a sensor 20 having a resistive bridge 21. First and second signals output due to imbalance and change in overall resistance of the bridge under the action of the respective first and second variable quantities are input to an electronics module 22. An application specific integrated circuit (ASIC) 46 carried by a printed circuit board (PCB) 23 processes the first and second signals with calibrated values held in an EEPROM 45 carried by a PCB 24 of the module 22, and outputs signals representative of the corrected true value of the first variable quantity and of the value of the second variable quantity. An advantage of the system is that power is supplied to the system and data measurements are output by the system over one pair of wires which is not possible if two sensors, one for each variable quantity, are used. The temperature values are thus emitted as independent signals and also used for temperature correction of the pressure values. The temperature correction uses a curve fitting method. The first variable may alternatively be load or torque. <IMAGE> |
