BikePower






Pair Networks
BikePower

NAME

BikePower - bicycle power-output calculator with command-line and Tk interface

SYNOPSIS

    use Tk;
    use BikePower;
    $top = new MainWindow;
    BikePower::tk_interface($top);

or

    use BikePower;
    BikePower::output();

DESCRIPTION

BikePower calculates power output and power consumption for bicycling. You give it things like riding speed, body weight, hill grade, and wind speed. The module returns power output and power consumption, broken out in various ways.

This module is meant for inclusion in own programs. There are two perl scripts in the distribution, bikepwr and tkbikepwr, for use as stand-alone programs.

CONSTRUCTOR

A new BikePower object is constructed with

    $bpwr = new BikePower [options];

Here is a list of possible options, which are supplied in a key-value-notion (e.g.

    $bpwr = new BikePower '-no-ini' => 1, 'V_first' => 20;

).

-no-ini
If set to true, do not use the defaults from ~/.bikepower.pl.
-no-default
If set to true, do not use any defaults (all parameters are left undefined).
imperial
Metric/imperial flag. If set, use imperial rather than metric units.
T_a
Temperature in °C.
given
Resolve for v (velocity), P (power) or C (consumption).
first_C
First consumption (Cal/hr) in table or other output.
first_V
First velocity (km/h) in table or other output.
first_P
First power output (Watts) in table or other output.
V_incr
Velocity increment in table.
P_incr
Power increment in table.
C_incr
Consumed_power increment in table.
N_entry
Number of entries in table, default: 10.
C_a
Air resistance coefficient.
A1
Linear coefficient of air resistance.
A2
Quadratic coefficient of air resistance.
A_c
Frontal area of the cyclist in meters^2.
T
Transmission efficiency of bicycle drivetrain.
E
Efficiency of human in cycling.
H
Velocity of headwind [meters/second].
R
Coefficient of rolling friction.
G
Grade of hill.
Wc
Weight of cyclist [kg].
Wm
Weight of machine and clothing [kg].
BM_rate
Basal metabolism rate [Watts/kg of body weight].
cross_wind
The wind given is a cross wind.

METHODS

calc
Resolve for velocity, power output or consumption (as stated in the "given" parameter) for the first_V, first_P or first_C parameter. The calculated values may be get with $bpwr->velocity, $bwpr->power or $bpwr->consumption.
output
Calculate and print a table with the supplied values.

INI FILE

The easiest way to create the ini file is to use tkbikepwr and clicking on the menu item "Save as default". The ini file is evaled as a perl script and should contain the variable $x as a reference to a hash. For example:

    $x = {
           'V_incr' => 2,
           'C_a' => '0.9',
           'A_c' => '0.4925155 (upright)',
           'Wm' => 19,
           'E' => '0.249',
           'G' => '0',
           'H' => '0',
           'first_C' => 500,
           'C_incr' => 100,
           'A1' => '0',
           'R' => '0.0066 (26 x 1.375)',
           'T_a' => 20,
           'T' => '0.95',
           'first_P' => 50,
           'given' => 'v',
           'Wc' => 68,
           'BM_rate' => '1.4',
           'P_incr' => 50,
           'cross_wind' => '0',
           'first_V' => 16,
           'N_entry' => 10
         };

TODO

    + better POD!

SEE ALSO

BikePower::Tk(3), bikepwr(1), tkbikepwr(1)

AUTHOR

Slaven Rezic (eserte@cs.tu-berlin.de)

Original program bike_power.c by Ken Roberts (roberts@cs.columbia.edu), Dept of Computer Science, Columbia University, New York and co-author Mark Grennan (markg@okcforum.org).

Copyright (c) 1997,1998,1999 Slaven Rezic. All rights reserved. This package is free software; you can redistribute it and/or modify it under the same terms as Perl itself.