Mailing List Archive

Mailing List: cavers

Message Display

The intertial is questionable due to the low speed. The accuracy came
from using cave raidios, an old trick which we also have, but do not use
at Wakulla. Now Stone has basicly made it so that we do not have to at
all - he showed how accuracte our survey is. Our mapper uses higher
power and has the sensors outside of the hull for better definition, but
ours are made for submarines.

  Our mapper fits anywhere we fit - theirs is a 400 pound , nine foot
long mess. 

  My take is that anyplace ther is a dispute involving survey accuracy ,
we get Stone and his mouths to come on back and clear it up. I want to
see some of these big time atheletes dive with no chamber and no
rebreather. I'll haul the tanks and do the recoveries.

John R. Rose wrote:
> 
> JoeL
> 
> > Any clue about how the WKPP mapper design compares to the USDCT's? The
> > Wakky II mapper was central to the project's success or failure since
> > they failed to deliver on the "tripple the distance" challenge, so I'd be
> > interested in what was similar/different.
> 
> The only information that I have on the USDCT comes from their public
> webpage, so I won't comment on their mapper. The WKPP mapper uses an
> electronically steerable beam that can be specified in 1 degree
> increments.
> 
> 
> > NASA has put up probes that map other astral bodies with great detail in
> > 3D, I'm sure this isn't beyond the curent state of technology, but I'd
> > like to see some actual maps.
> 
> Sonar mapping in a cave is complicated by the strong multipath echoes
> that are produced when the signal ricochets off the cave walls. The
> geomemetry of the cave and the smoothness of the walls with respect to
> the frequency of the signal determines the degree to which multipath
> signals are a problem. This is more complicated than interpreting sonar
> data in open water. There are techniques for distinguishing between
> direct echoes and multipath echoes. The USDCT signal processing people
> may or may not be aware of these.
> 
> -John

Navigate by Author: [Previous] [Next] [Author Search Index]
Navigate by Subject: [Previous] [Next] [Subject Search Index]

[Send Reply] [Send Message with New Topic]

[Search Selection] [Mailing List Home] [Home]