Several channel ultrasonic parking radar/sonar

[htteam]

Need schematic for this project. I make a single channel sonar, but have throuble in multi-channel version. Pls. advice.
Best regards.

[karpen]

I'm doing the same thing, and have some thoughts about how to do it. I don't have full schematics ready yet (will post when, if ever , I'm ready).
But maybe my solution won't work with your design. If you'd post your design, I'd be happy to check if it would work.

[tuvoj]

Why not just tri-state the outputs (or open=collector tied) and multiplex single-units with a small micro-controller like a PIC or such...

I have done this with the Parallax Ultrasonic ranging modules, with 4 units on a tri-stated input bus to a PIC '84F which does the multiplex by toggling the enable inputs on each Parallax module, to know which is active output on each serial module scan.

Cheers-Tuvo

[ambo]

If you are not a bit concerned about weatherproof sensors, a very good candidate would be a the lv-maxsonar from maxbotix.  It already incorporates a mcu so the output of the sensor as an analog voltage proportional to distance, or as serial data or pwm data.  You can just interface them directly into a mcu to get and process the data immediately.