3 ms·
I worked briefly with a company that manufactured surveying equipment back in the mid 2000's and they had a similar setup (single sensor though). They could ge
by jcims 6y ago
I worked briefly with a company that manufactured surveying equipment back in the mid 2000's and they had a similar setup (single sensor though). They could get sub-millimeter precision as well, but they had to 'chirp' the light power modulation from very long (e.g. 1km) to short (sub millimeter) in order to remove any aliasing that would occur when the distance was a multiple of the measurement baseline.
If these are 90 degrees out of phase I don't know how they eliminate that possibility without doing something similar. (e.g. imagine the modulation is at 30MHz and your measurement interval is 10m, how would you differentiate between 20.034m and 30.034m?
- opwieurposiu 6y agoThe kinect does do the "chirp", but this detail is omitted from TFA.
- rzw2 6y agoThe microsoft kinect does 3 frequency measurements to get the higher distance precision of higher modulation frequencies and to extend the maximum distance so the phase wrapping (aliasing) can be solved. Based on some Microsoft patent filings and other research papers I wrote a short article on possible phase unwrapping methods on iToF sensors, https://medium.com/chronoptics-time-of-flight/phase-wrapping-and-its-solution-in-time-of-flight-depth-sensing-493aa8b21c42 https://medium.com/chronoptics-time-of-flight/phase-wrapping...
- jcims 6y agoFantastic article!!! They definitely need your animations, it's way more intuitive.
- rzw2 6y agoThanks, got any references to how the surveying equipment de-aliasing method worked?
- jcims 6y agoI don’t unfortunately. I was there doing an information security assessment and the guy I was working with was one of the product engineers. When I wrapped my work we spent another hour or two just talking about their products and how they worked.