Patent Number: 053368940
Section: abstract

The controller for a single infrared source is capable of being programmed to act as a target for an AIM-9 target seeker. Data are read by the controller comprises (a) temperature data, (b) aperture data, (c) shutter-filter data, and (d) missile ID data. The controller includes a microprocessor CPU, with a program stored in a read only memory. The CPU reads aperture data from the stand, compares the data to signals derived from a potentiometer coupled to an aperture wheel, operates a motor to select an aperture on the wheel, and then sends an aperature ready signal to the stand. For temperature control, the black body is part of a resistance bridge circuit. A plurality of MOSFETs are used to select a value of resistance for a reference voltage in the bridge. The CPU reads temperature data from the stand and uses it to control the MOSFETs. An instrumentation amplifier across a diagonal of the bridge has its output coupled to a transistor circuit which controls power to the bridge, which thereby controls the temperature and resistance of the black body. The CPU reads shutter-filter data from the stand, and uses the data to generate signals to control solenoids for a shutter and two filters which are part of the IR heat source. A black body protection circuit opens a solid state relay to disable the 24-volt power supply to the bridge when the thermocouple indicates a temperature of approximately 905 degrees C. The results of testing this circuit shows that the fuse for the 24-volt supply will blow or the black body temperature will be maintained at approximately 905 degrees.