Curb feelers or curb finders are springs or

wire Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is c ...

s installed on a vehicle which act as "

whiskers Vibrissae (; singular: vibrissa; ), more generally called Whiskers, are a type of stiff, functional hair used by mammals to sense their environment. These hairs are finely specialised for this purpose, whereas other types of hair are coarse ...

" to alert drivers when they are at the right distance from the

curb A curb (North American English), or kerb (Commonwealth English except Canada; see spelling differences), is the edge where a raised sidewalk or road median/central reservation meets a street or other roadway. History Although curbs have ...

while parking. The devices are fitted low on the body, close to the wheels. As the vehicle approaches the curb, the protruding feelers scrape against the curb, making a noise and alerting the driver in time to avoid damaging the wheels or

hubcap A hubcap or hub cap is a decorative disk on an automobile wheel that covers at minimum the central portion of the wheel, called the hub. An automobile hubcap is used to cover the wheel hub and the wheel fasteners to reduce the accumulation of ...

s. The feelers are manufactured to be flexible and do not break easily.

Hotrods

Curb feelers are still used on some hot rods when a 1950s look is wanted. They are especially popular for cars with

whitewall tire Whitewall tires or white sidewall (WSW) tires are tires having a stripe or entire sidewall of white rubber. These tires were most commonly used from the early 1900s to around the mid 1980s. Background The use of whitewall rubber for tire has be ...

s, which are easily marred when scraped against the curb. Sometimes curb feelers are found only on the passenger side of the car, since that is most commonly near the curb when parking. Sometimes they are added only next to the front wheels. Some curb feelers have a single wire or spring, while others have two to increase the area that can be protected. Any particular car may have just one curb feeler installed (as on the pictures) or more if attached near the front and rear, as well as on both sides of the vehicle.

Recreational vehicles

Recreational vehicles sometimes have rubber feelers or metal, antenna-like rods mounted on the lower part of the body that act as feelers so that drivers are warned if they are approaching a curb or other obstruction, thus reducing the chances of gouging or even cutting the tire sidewalls and generally increasing the safety of vehicle operation.

Buses

Bus A bus (contracted from omnibus, with variants multibus, motorbus, autobus, etc.) is a road vehicle that carries significantly more passengers than an average car or van. It is most commonly used in public transport, but is also in use for cha ...

es are sometimes fitted with curb feelers, which can assist the driver in ensuring that the bus is close enough to the curb to allow passengers to step to and from the curb easily.

Heavy equipment

Today, the

U.S. Department of Labor The United States Department of Labor (DOL) is one of the United States federal executive departments, executive departments of the federal government of the United States, U.S. federal government. It is responsible for the administration of fede ...

Mine Safety and Health Administration mentions that users of heavy equipment can benefit from an

analogous Analogy (from Greek ''analogia'', "proportion", from ''ana-'' "upon, according to" lso "against", "anew"+ ''logos'' "ratio" lso "word, speech, reckoning" is a cognitive process of transferring information or meaning from a particular subject ...

accessory:

In the 1950s, cars were often equipped with curb feelers. ..Using a piece of conveyor belt, long by wide and a couple of pieces of angle
iron Iron () is a chemical element with Symbol (chemistry), symbol Fe (from la, Wikt:ferrum, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 element, group 8 of the periodic table. It is, Abundanc ...
, you can make a pinch-point feeler, a warning device for the corners of a continuous miner. This will give a warning nudge to anyone in the danger area, giving him or her about a running start to stop the machine or to yell at the operator to stop. The belting is stiff enough to hold its shape but flexible enough to give if it runs into a miner or vice versa. The flexibility also allows this "curb feeler" to drag against the rib or be smacked by a shuttle car with little or no damage. A little spray from a can of reflective paint will make the belt a visual warning device as well. One or two on each corner will help or put as many as you want.

Electronic sensors

Curb feelers based on optical technology are designed to function the same way but work in the proximity of an obstruction rather than having to come into physical contact with it. As described by one

United States patent Under United States law, a patent is a right granted to the inventor of a (1) process, machine, article of manufacture, or composition of matter, (2) that is new, useful, and non-obvious. A patent is the right to exclude others, for a limited ...

An electronic curb feeler system uses two pairs of optical sensor units to detect an object located near the front end of a vehicle during parking. One pair of optical sensor units detects an object directly in front of a left portion of the front end of the vehicle while another pair of optical sensors detects an object directly in front of a right portion of the front end of the vehicle. By supplying the operator of the vehicle with the location of the object as well as the exact distance the object is from the front end of the vehicle the operator can avoid hitting the object while parking very close to the object.

Devices such as this, and simpler electronic devices similar to the original wire curb feelers used on cars, are used in the design of various mobile

robotic Robotics is an interdisciplinary branch of computer science and engineering. Robotics involves design, construction, operation, and use of robots. The goal of robotics is to design machines that can help and assist humans. Robotics integrate ...

devices. One robotics company that does work for the

United States Department of Defense The United States Department of Defense (DoD, USDOD or DOD) is an executive branch department of the federal government charged with coordinating and supervising all agencies and functions of the government directly related to national sec ...

uses

laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The fi ...

-assisted curb feeler technology.

References