Speedometer is the most prominent gauge among the cluster of dashboard instruments of an automobile. The job of the speedometers is to indicate the speed of an automobile in miles per hour, kilometers per hour or both. The earlier speedometers were expensive and available only as options. But after 1910 the automobile manufacturers began to include the speedometer as standard equipment. One of the first speedometer suppliers was Otto Schulze Autometer (OSA), a legacy company of Siemens VDO Automotive AG.
There are two types of speedometers: Electronic Speedometer and Mechanical Speedometer. The Electronic Speedometer is actually modern day speedometers that are being used at the same pace as of mechanical speedometers.
Another form of speedometers i.e. Digital Speedometers have now been popularly used in hybrid vehicles.
Functioning of Speedometers:
The functioning of Speedometers depends upon their types. The Traditional Speedometers or Mechanical Speedometers are driven by a flexible cable, rotated by a set of small gears in the tail shaft of a transmission. But, the modern day Speedometers or you can say, the Electronic Speedometer works differently. These Speedometers are connected to a navigation device that periodically corrects corrected data of a traveling distance per a pulse on the basis of a GPS signal and a vehicle speed pulse signal from a vehicle speed sensor, and outputs the corrected data to a navigation correction information data storage section of the Speedometer.
Error in speedometers:
Errors in Speedometers are commonly seen and felt by the users. Speedometers are not totally accurate and most speedometers have tolerances of some 10% plus or minus due to wear and tear on tires as it occurs. Modern speedometers are said to be accurate within 5% but this may not be entirely correct. Excessive speedometer error after manufacture, can come-of from several reasons, but most common of all is due to nonstandard tire diameter.
How Speedometers Work?
The dashboard instrument cluster in your car organizes a variety of sensors and gauges, including the oil pressure gauge, coolant temperature gauge, fuel level gauge, tachometer and more. But the most prominent gauge -- and perhaps the most important, at least in terms of how many times you look at it while you're driving -- is the speedometer. The job of the speedometer is to indicate the speed of your car in miles per hour, kilometers per hour or both. Even in late-model cars, it's an analog device that uses a needle to point to a specific speed, which the driver reads as a number printed on a dial.
As with any emerging technology, the first speedometers were expensive and available only as options. It wasn't until 1910 that automobile manufacturers began to include the speedometer as standard equipment. One of the first speedometer suppliers was Otto Schulze Autometer (OSA), a legacy company of Siemens VDO Automotive AG, one of the leading developers of modern instrument clusters. The first OSA speedometer was built in 1923 and its basic design didn't change significantly for 60 years. In this article, we're going to look at the history of speedometers, how they work and what the future may hold for speedometer design.