3 ms·
Thank you so much for releasing this. I have several personal projects were this can be useful. One variation I’m thinking about and want your opinion on. I’m
by jsjohnst 7y ago
Thank you so much for releasing this. I have several personal projects were this can be useful.
One variation I’m thinking about and want your opinion on. I’m building a circuit that VERY precisely (think <1ms accuracy) marks the start and end of when a high speed object passes the field of view. The exact scenario is a bit hard to describe if you aren’t familiar with the subject area, but an analogy that works well is imagine having two sets of cones laid out on the ground with 10 meters between the groups. Then imagine a car doing 100mph between the two sets of cones. What I need to be able to answer is:
- did the car go between the first set of two cones?
- what’s the exact time it went between them?
- did the car go between the second set of two cones?
- what’s the precise time it went through the second set?
- what’s the calculated speed between the two sets?
The real scenario isn’t touching the ground, so anything pressure sensitive doesn’t work. I’ve been currently experimenting with using lasers on both the start and end gates and an fpga doing the calculations, but I’d love if I could do this with a single laser setup using a scanning setup like yours.
Can you speak to how hard it would be to use something like this to precisely (1ms or better accuracy) measure a low flying object between a starting and ending point?
- OnACoffeeBreak 7y agoI am not the OP. Seems like you should be able to set up two break beam detectors: one per set of cones. Process detector output into digital form where you get a pulse when the detector is broken. Connect them to a microcontroller input and use a fast counter in input capture/compare mode to measure time between pulses. A counter running at 1 MHz (1 us) should do.