The drop sensor is constructed from two sequential optical sensors at a fixed altitude above the drop target. The optical sensors must allow a ball to pass through them, work in ambient light, and have a small rise time to reduce sensing delays. The Contrinex LGS-0030-005-502 fork through-beam sensor meets these requirements and can be mounted on an adjustable housing, allowing drop sensor accuracy to be tuned. Increasing the sensor separation will increase measurement accuracy, but at the cost of shrinking the drop interval.
|no-load supply current||< 30||mA|
|voltage drop||< 2.8||V|
|output signal rise time||250||us|
When powering from the 15V power supply from the Luminary, the output voltage must be divided to 5V or less to prevent damage to the Luminary GPIO pins. This is accomplished with a simple voltage divider. Since two sensors are used but only one will be active at a time, a diode OR gate connects both sensors to a single input pin.
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