Odometers are instruments that are used to measure the distance traveled by an automobile or some other type of vehicle. If you’re selling a used automobile, you’re legally required to sign an odometer disclosure statement in which you certify that the mileage indicated on your odometer at the time of the sale is accurate. This is one of the many reasons why it’s important to make sure your odometer is measuring distances accurately. If you think your odometer may not functioning properly, there are services that offer instrument repair Orlando that can fix it.

How Do Odometers Work?

Mechanical odometers operate by means of a cable that stretches from the automobile’s instrument panel to the output shaft of the transmission. Special gears on that shaft engage the cable so that the odometer will register distances in miles and tenths of miles. Some older cars may still be outfitted with mechanical odometers. Mechanical odometers are also commonly found on bicycles. In theory, at least, mechanical odometers are rewindable, which means unscrupulous sellers may be tempted to tamper with them.

Newer cars use digital odometers, which are programmed to the circumference of the car’s wheels. These odometers attach to the wheels by means of a magnet and a pickup that’s attached on a nearby point of the car’s chassis. Every time the wheel revolves, the magnet passes by the pickup, thereby generating an electrical spike. The car’s computer uses these spikes to calculate the distances traveled by the car.

A Brief History of Odometers

References to odometers can be found in histories of the Punic Wars, but the first documented design for one dates back to 27 BC. A Roman civil engineer named Vitruvius invented a mechanical odometer that was geared to the circumference of chariot wheels. When Renaissance scientist and artist Leonardo da Vinci tried to make a working model of the device, however, he failed to be able to do so.

Speedometers with digital readouts were first introduced in the late 1980s and early 1990s. They were unpopular with motorists who complained of being unable to see them in strong sunlight. Digital odometers remain the automotive industry standard, but these days, they are attached to analog gauges.