Sonar Questions...

Archiver

Hello Everyone,

I've just got my first Polaroid 6500 sonar ranging module up and running
w/a BS2. I know that this topic has been covered many times, but I have a
few questions that I haven't seen covered.

1 - None of the documentation explains just what type of output is provided
from the ranging module to the microcontroller host. The code examples
I've seen use "RCtime" to read the result - leading me to believe that the
output is a resistance proportional to the measured distance. Is this
correct? Would I get more resolution using an ADC to read the module
result?

2 - Polaroid says that the typical absolute accuracy is +/- 1% of the
reading over the entire range. Is this optimistic from the module itself
and, is the BS2 capable of performing the math to make this obtainable?
What have your experiences been? I'm measuring a distance of no more than
10 feet and would like a resolution of +/- 1/8 of an inch if possible and
can settle for +/- 1/4 of an inch.

All of the module modifications listed at Acroname have been performed
and it's running well, but my BS2 math is very week and it would be very
helpful to know just what output is comming from the ranging module. Using
the Acroname code example I'm currently reading to the nearest whole inch.

Thanks for the help and support that all of you are,

Tim Medema
CrystaLite, Incorporated
Everett, Washington
timm@c...

Archiver

I've also been working with the 6500 board if you send me some of your code
I may be able to help.

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Original Message

---

From: Tim and Jo <dema@t...>
To: Basic Stamp List <basicstamps@egroups.com>
Sent: Wednesday, November 29, 2000 5:16 AM
Subject: [noparse][[/noparse]basicstamps] Sonar Questions...


> Hello Everyone,
>
> I've just got my first Polaroid 6500 sonar ranging module up and
running
> w/a BS2. I know that this topic has been covered many times, but I have a
> few questions that I haven't seen covered.
>
> 1 - None of the documentation explains just what type of output is
provided
> from the ranging module to the microcontroller host. The code examples
> I've seen use "RCtime" to read the result - leading me to believe that the
> output is a resistance proportional to the measured distance. Is this
> correct? Would I get more resolution using an ADC to read the module
> result?
>
> 2 - Polaroid says that the typical absolute accuracy is +/- 1% of the
> reading over the entire range. Is this optimistic from the module itself
> and, is the BS2 capable of performing the math to make this obtainable?
> What have your experiences been? I'm measuring a distance of no more than
> 10 feet and would like a resolution of +/- 1/8 of an inch if possible and
> can settle for +/- 1/4 of an inch.
>
> All of the module modifications listed at Acroname have been performed
> and it's running well, but my BS2 math is very week and it would be very
> helpful to know just what output is comming from the ranging module.
Using
> the Acroname code example I'm currently reading to the nearest whole inch.
>
> Thanks for the help and support that all of you are,
>
> Tim Medema
> CrystaLite, Incorporated
> Everett, Washington
> timm@c...
>
>
>
>
>
>