In Reply to: ultrasonic distance meter posted by arumugam on 11/06/02 at 12:35 AM:
Have you looked at:
If you want to do it yourself:
1) Determine the accuracy and precision you need.
2) Determine the beam width you need.
3) Based upon that select the frequency you need.
Possibly the number of transducers needed to shape the ultrasonic beam.
3) Select a transducer (s)
4) Design a driver
5) Based upon the drive power, transducer, distance, and beamwidth specify the reciever you need.
(Possibly the same transducer?)
6) Design a reciever circuit that meets the requirements.
7) Make a simple circuit that will deliver the comparison between transmission time and recieve time to a uP.
8) Find a suitable interface to the uP. A/D, threshold, etc... depending upon the detection method.
9) Program the uP to accept the interface/detection information and make it available to the user.
Most of messages on this board indicate that the people have a solution and don't need to do step 1 above. These people are called hobbyists. This is fine and they should go to one of the sites I mentioned earlier. Any professional engineer knows that steps 1 and 2 are what is needed for a product/design that forfills some real goal.