Descent: 0 feet (0 m)
Description:
Starting from Hwy 9 (the flat section before the climbing begins),
Tollgate begins with its worst grades, at 16-17% for 200 yards. Then
it flattens out for a while, and then climbs a little more at a more
modest 12-14%. Beyond this profile, Tollgate continues as a
dead-end, but Saratoga Heights will take you to Pierce Road in
another half mile.
Altimeter altitude
(Altitude linearly interpolated from altimeter
samples, and smoothed with a 0.04mi gaussian.)
Each horizontal line is 100 feet. Each vertical
line is 0.2 miles. Gradiometer grade
(Grade linearly interpolated from gradiometer
samples, and smoothed with a 0.04mi gaussian.)
Each horizontal line is 2% grade. Each vertical
line is 0.2 miles. Altimeter grade
(Grade linearly interpolated from altimeter
samples, and smoothed with a 0.20mi gaussian.)
Each horizontal line is 2% grade. Each vertical
line is 0.2 miles. Comparison of grades
(Green grade is from the gradiometer, magenta grade
is from the altimeter, and white is where they
overlap.)
Each horizontal line is 2% grade. Each vertical
line is 0.2 miles.
Overall (averaging my first 20 hills),
the gradiometer grade averages 0.63 (% grade)
higher than the altimeter grade, with a standard
deviation of 4.5 (% grade per road).
This error may be due to:
-
Uneven sampling -- I take more samples when the
hill gets steep.
-
Calibration error (of the gradiometer or
altimeter).
In the end, though, I think that each individual
sample is accurate to within about 2% for that
instantaneous segment of road. My results may
not always agree with my altimeter, but they are
generally repeatable within 1%. I think that
I just need to take more samples to generate
more accurate graphs.
Raw Data:
Dist Grade Alti. Location
---- ----- ------ --------
0.00 8% 580 start - Highway 9
0.02 16% 590 "speed limit 25" sign
0.08 17% 650 21196 Tollgate
0.12 16% 680 end of steep section -- flattens out
0.17 7% 700 gentle grade, rolling now
0.30 0% 750 21359 Tollgate
0.41 14% 780 just started climbing again
0.48 14% 840 "limited sight distance - 20 MPH" sign
0.52 0% 850 Saratoga Heights
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Lucas's
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