Cyclocomputer

A bicycle computer ( Swiss VeloComputer ) or bicycle speedometer is an electronic device for continuous measurement of speed and distance traveled when cycling. Almost all bike computers have additional features, such as displaying the time and cadence.

  • 3.1 GPS
  • 3.2 smartphones and PDAs

History

Even the advent of cycling the desire, especially when training data over distances driven and reached speeds was to receive. Simple mechanical solutions that have been developed subsequently, were Odometer and bike speedometer.

Odometer

When a counter odometer was increased by a counting amount by a driver attached to the spokes on each revolution. Since the distance with each revolution of the wheel path is equal to the circumference of the wheel, each matching odometer were offered for different rim diameter. An inaccuracy resulted from the fact that can be mounted with different rolling circumferences on rims with the same diameter tires. Most odometer were directly attached to the front fork of the bicycle. Despite the great distance to the face of the driver most odometer were read while driving.

Mechanical Speedometer

A further constitute mechanical tachometer, the addition indicated the speed. Here a pickup on the axle of the front wheel was mounted, which was coupled to the commonly attached to the handlebar display unit by a flexible shaft to the transducer. These tachometers were offered to match the rim size. The display unit was uniform for most for all wheel sizes, only the translation of the drive or pickup the wheel size has been adjusted. Some models had next to the odometer trip odometer. Mechanically driven speedometer for common tire sizes are still considered " retro" products available in various designs.

Electronic speedometer

With the development of microelectronics and LCD screens as small devices could be manufactured with low power consumption for mobile use from the 1980s. At this time the first cycle computer came on the market. The operating principle has remained the same in most cases: A small magnet on a spoke induced in a coil attached to the fork of a voltage pulse; alternatively solves the spoke magnet from a magnetic switch. This signal is used for the display unit, the actual computer forwarded. Earlier this happened only with the help of a cable, since about 1995 ( and rising ) and wireless systems available. The latest generation of bike computers used coded digital signals, which are susceptible to electromagnetic interference barely. The pulses are counted electronically, processed and finally displayed in the desired units. The devices do not need to be produced for a specific wheel size because the wheel circumference can be adjusted to the millimeter.

Bicycle Computer

The progressive development of the electronics made ​​it possible in the 1990s to incorporate many additional features. Meanwhile standard are average speed and maximum speed.

Other common features are:

  • The measurement of cadence on a mounted next to the crank sensor
  • Determining the height above sea level ( usually via a barometric altimeter )
  • The measurement of ascent/des- incl summary of the vertical drop
  • The measurement of the heart rate with a chest strap
  • The estimate of the calories consumed by heart rate, taking into account gender and mass of the driver
  • The clock display
  • The display of the temperature
  • Use on two bikes with separate kilometers and driving time counters
  • The possibility of data storage and transfer to a PC, allowing new ways of training evaluation were created.

Circumference

The rolling circumference depends not only on the specified rim size ( eg, 26 or 28 inches from ), but also on the tire width, because the wider a tire is, the higher its side walls. The following values ​​can serve as guidance:

Alternatives

GPS

Since about 2002, there are GPS units that are only slightly larger than wristwatches. Regular determination of the position enables the display of the basic data, that is, the speed and distance traveled. Often the amount is displayed but on principle rather inaccurate. Better models have a more accurate barometric altimeter. A record is used for future evaluation of the ride. Some outdoor GPS devices can also receive, display and record data from different sensors ( speed, cadence, heart rate ).

Smartphones and PDAs

Even some smartphones and PDAs are with appropriate software, equipment (especially the GPS ) and optional cadence sensor as a bike computer. However, these devices are not generally protected from rain and often only have a short battery life. It should therefore be taken in the choice of software on power saving features. Due to the entrainment of additional or external batteries, the runtime can be extended. For safe and well protected from rain attachment to the bike corresponding brackets are offered in stores. As an additional feature compared to dedicated bike computers offer some apps for smartphones to the display of driving history on cards, it can be a navigation along the recommended bicycle routes take place, and the traveled routes can be recorded. For the pulse recording and calculating the calories burned, a training computer or a heart rate monitor is additionally carry when needed.

Velocity Cadence (cycling) Cycle sport Perimeter Electromagnetic induction Grade (slope)
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