Ping))) Stand
EmilyP
Posts: 21
Hey Parallax Guys,
The Ping))) Stand is a great idea but why so short? I found that my Ping))) sensor works best at 7 inches or more off the ground. I would buy the Ping))) stand if it were taller or adjustable to a taller size but for now I will stick to my lame lego stand.
Thanks,
Emily
The Ping))) Stand is a great idea but why so short? I found that my Ping))) sensor works best at 7 inches or more off the ground. I would buy the Ping))) stand if it were taller or adjustable to a taller size but for now I will stick to my lame lego stand.
Thanks,
Emily
Comments
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PG
2) Because the PING))) is tuned to the 40KHz frequency of the sound pulse, it takes something on the order of a cycle, maybe a 1/2 cycle to react to the incoming waveform. A wavelength is about 0.7cm at 40KHz, so figure that the resolution is somewhere around 0.5cm. That's over the full path length (out and back). In terms of distance to the object, divide by two. This is also temperature sensitive, so it will depend on temperature variations in the area and on air currents. The PULSIN statement that measures the width of the logic pulse from the PING))) resolves the time to 2us units.
I may be wrong about the "exact" resolution, but there would need to be a substantial portion of a full wavelength received to get enough energy at 40KHz to detect unambiguously.