Can anyone recommend an IR distance sensor that works on black surfaces? I'm looking for something to use as a "cliff" sensor, to help a small mobile robot avoid falling down stairs or off a table, and I thought the Sharp GP2Y0D805Z0F would work. However, after testing it, I found any matte black surface does not register with the sensor, meaning the sensor would falsely report a dark carpet as a dropoff.
Sharp has some other models that might better handle this, but they're all much larger and more expensive. What type of sensor is good at detecting ledges and other dropoffs, but is small and inexpensive and works with a wide range of surfaces?