| 摘要 |
<p>A Battery powered sensing device using an analog sensor has electronic circuitry that maintains sensitivity and calibration of the sensing device during quiescent periods with very little power drain. In one implementation, a joystick is provided with a sensitive analog sensor, such as strain gauges, connected to the shaft of the joystick. The strain gauges are connected in a bridge circuit across which a voltage is applied. Three operational amplifiers are connected to combinations of the strain gauges in the bridge circuit to generate X, Y and Z output voltages corresponding to the combined signals generated by the strain gauges. A microprocessor receives outputs from the sensitive analog sensor and generates a sample signal and performs a recalibration of sampled signals during periods of inactivity. The sampling interval for recalibration is increased in periods of extended inactivity, greatly reducing the current draw on the battery power supply and greatly reducing power requirements of the sensing device. <IMAGE></p> |
