Re: garmin vista Cx odometer - height taken into account?

On 30 Jul 2006 08:07:45 -0700, "Ben" <Benjamin.Barker@xxxxxxxxx>
wrote:

Thanks - that would certainly work. The odometer readings seem very
accurate around here, but cambridgeshire doesn't really have any hills!

Not really needed, nor is any real point. Just set any
arbitrary point some miles away, then set the altitude of the point to
the same altitude as your own location. Then reset the altitude of the
distant point to a few thousand feet and see if the distance changes.

Then do the exercise on a map with pencil and paper as a check
if you wish. I'd suggest using a map of southern California for a
realistic test because:

Mount Whitney is the highest point in the contiguous United States at
elevation 14,505 feet (4,421 meters). It is located at the boundary
between California's Inyo and Tulare counties. The western slope of
the mountain lies within Sequoia National Park.

Mount Whitney was named after Josiah Whitney, the chief geologist of
California. It was first climbed in 1873 by Charles Begole, A. H.
Johnson, and John Lucas (fishermen who lived in Lone Pine,
California.)

Mount Whitney is just 76 miles (123 km) west of the lowest point in
North America, in Death Valley (282 feet (86 m) below sea level), and
immediately rises just over 2 miles (~3300 m) in elevation above the
floor of the Owens Valley.

Funny that people rarely seemed to question the difference
when only paper maps were common. Maybe because the difference in
distance due to altitude change was down in the noise, compared to
that introduced by the excursions from a straight line of the road
from one point to another.

It would be pretty basic trig to take height into account, and since
the Cx unit has a barometer to measure altitude, and the unbit polls
once a second, it would be pretty accurate.

I don't currently have access to the GPSr, but will post a reply when
I've checked it out :-)

Ben



Jack Erbes wrote:

Ben wrote:

Does anybody here know whether the vista Cx takes vertical changes in
position into account when working out distance travelled? If I were to
climb vertically up 100m would it register 100m distance, or zero...?


You could test that by setting a far distant waypoint with an altitude
the same as is displayed for your present position. Then look at the
waypoint from your position and you'll see the distance to it.

Edit the waypoint and add a large amount of altitude to its location.
then check the distance again.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

.

Relevant Pages

  • Re: Northrop Grumman to Buy Builder of SpaceShipOne, First Manned Commercial Space Rocket
    ... the passengers brief moments of weightlessnes. ... They were also in space according to the altitude record they set. ... feet or 69.6 miles above the Earth's surface. ... capable of controlled flight over a minimum distance. ...
    (sci.space.policy)
  • Re: Rating cell phone calls [telecom]
    ... regardless of time, out to 15 miles, they're still a 'local' call, ... distance-related charge scheme, but the distance is taken from the point ... we had another change in local calling rates. ... I have a vague recollection of when pay phone rates were raised from 25 ...
    (comp.dcom.telecom)
  • Re: Rating cell phone calls [telecom]
    ... of time, out to 15 miles, they're still a 'local' call, but you _are_ billed ... distance-related charge scheme, but the distance is taken from the point ... There is/was a fourth band 'D', ... were merged into an untimed calling area for residential, ...
    (comp.dcom.telecom)
  • Re: Rating cell phone calls [telecom]
    ... of time, out to 15 miles, they're still a 'local' call, but you _are_ billed ... choices among measured service with units, a pre-paid local calling area ... and distance rated) or a larger pre-paid local calling area with calls ...
    (comp.dcom.telecom)
  • Re: OOTT://In case it is important to you.
    ... I set a Personal Record for running distance I've been trying ... Hey, what did you hit. ... I did run my first marathon this year at 62, didn't do so hot, ... I ran 10 miles yesterday. ...
    (rec.woodworking)