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Definitions
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| Track |
A track
is the breadcrumb trail that the GPS device logs. Every period (adjustable) the GPS device stores the current position, time and height (not
all devices provide height, other devices provide an additional heartbeat
again). A track is a list of all these points.
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| Route |
If you
start a trip, you can use a predefined route. Your GPS is doing its best to
give you the right directions. A route whose format is not much different than one
track, but obviously lacks some specific characteristics. These are the time and the height, because usually in the route maps are not
available.
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| GPX file | This is the output file from the garmin (garmin XML). The format is described by Garmin, but the
underlying basis is XML making it a good exchange format.
A file can GPX tracks, routes and waypoints. These are all shown on
Mytracks.me. Mytrack.me expects at least one track in the file exists,
otherwise an error message follow.
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| Colindex |
This is
an index which indicates the heaviness of a climb (col in french), according to the Dutch magazine
'Cycle'. This index can also naturally be applied to the whole trip. The same
formula is then applied, which some assumptions.
Colindex = 0.0001 * altitude difference ^ 2 / (length / 2) (altitude difference [m],
trip length in [km])
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| A GPS device |
A GPS
system is usually a small device that is capable of measuring satellite-based position on earth. The device stores the location in a track on a regular basis. Beside geographic
location usually the height and time are saved.
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American Measures
| This site uses some American measures :
1 mile = 1609.344 m
1 foot = 0.3048 m
1 pound = 0.45359237 kg
| | Energy |
Cycling costs energy. From a day trip, with reasonable speed, you can
easily burn hundreds kilocalories (kCal). The total energy consumed is the
sum of power times the time (the integral for the mathematicians among us).
For example for 100 seconds 100 watt power kicking, you have a work performed
or energy supplied by a 100 * 100 = 10,000 Joules (J). The Joule is a measure
of the amount of energy. Other known units of energy are the kilocalorie
(kCal), and the kilowatt hour (kWh). These are easy to convert each other. (1
kCal = 4.2 kJ, and 1 kWh = 3600 kJ). The website http://www.xs4all.nl/~janfreak/drag.html gives an example of how speed and climb
meters can be converted into power and energy. The GPX file provides all the
information for that calculation to perform. So do we. This amount of energy
that can be calculated from the GPX file, may significantly differ from the
indication that a heart rate monitor indicates. That calculates the total number
kCal consumed by the body. In contrast, only a small portion is converted into
kinetic energy. On the internet I find factors (efficiency) of 25%. I think the
performance of the human body is worse. Who can help me with a better indication of the
efficiency of the human body?
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| Power |
While cycling you have to overcome serveral kinds of forces. Roughly there are three forces at
work on you when you go forward: the resistance of the bands on the road,
including the resistance of chain and bearings, air resistance and the slope.
The GPS unit determines speed and altitude. It is easy to calculate the
generated power. The sum (actually the integral) of all power bits per time
unit, provides the total delivered energy or work.
The calculation on MyTracks is done with the formula:
Power = (Cr * m * g + ρ
* Cw * A * v ^ 2 + m * g * slope) *v
With
Cr = a
cycle-dependent parameter, set in 0003 at MyTracks
m = bike + rider + luggage weight in kg
g = gravitational acceleration (= 9.81 kgm / s ^ 2)
ρ = density of air (=
1.2 kg / m ^ 3)
Cw * A = resp. the drag coefficient and projected area (on MyTracks: Cw * A =
0.39)
slope = slope percentage/100
v = velocity
To successfully carry out this calculation some assumptions made, and
you will be asked to pprovide a few extra parameters. in this case of the cyclist,
including bike and luggage. The wind direction and strength are
required. This ingredients are present to calculate the power with a reasonable accuracy.
The official unit for power is the watt (W).
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| Wind speed |
Wind
speed can be expressed in different ways. This site is the Beaufort (bft)
used. The following table can help you to convert wind speed.
| Strength (bft) |
description |
Speed in km/h |
Speed in m/s |
Speed in kts |
| 0 | Still | 0-1 | 0-0.2 | 0-1 |
| 1 | Weak | 1-5 | 0.3-1.5 | 1-3 |
| 2 | Weak | 6-11 | 1.6-3.3 | 4-6 |
| 3 | Moderate | 12-19 | 3.4-5.4 | 7-10 |
| 4 | Moderate | 20-28 | 5.5-7.9 | 11-15 |
| 5 | Rather strong | 29-38 | 8.0-10.7 | 16-21 |
| 6 | Powerful | 39-49 | 10.8-13.8 | 22-27 |
| 7 | Hard | 50-61 | 13.9-17.1 | 28-33 |
| 8 | stormy | 62-74 | 17.2-20.7 | 34-40 |
| 9 | Storm | 75-88 | 20.8-24.4 | 41-47 |
| 10 | Storm | 89-102 | 24.5-28.4 | 48-55 |
| 11 | Very heavy storm | 103-117 | 28.5-32.6 | 56-63 |
| 12 | Hurricane | > 117 | > 32.7 | > 63 |
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Read more news....Guestbook
September 5, 2024
Cyclin..
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Hallo, ik heb een account "Stanne57" Om reden die ik niet weet kan ik niet meer inloggen
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May 24, 2018
jcob1374
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Hebt u een verklaring waarom bij mijn opgeladen track nr. 47 (Himmerod) en track
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April 5, 2016
jongst..
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Hoe kan ik een opgeslagen track weer exporteren naar mijn eigen bestand?
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September 9, 2015
jakke
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Gerard zijn er soms problemen met de site,sinds gisteren is hij heel traag en de
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May 16, 2015
henkstap
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Heb me vandaag aangemeld bij My Tracks.me. Ziet er mooi uit! Het enige dat ik niet
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