Vehicle backing aid

Abstract

A method and apparatus is provided for alerting the operator of a vehicle as to the distance from the rear of the vehicle to a structure such as a loading dock to which the vehicle is being backed through the utilization of sonar ranging and means for converting a detected range into an audible call out of the distance from the back of the vehicle to the structure to which the vehicle is being backed. In one embodiment the talking unit is activated upon the placing of the vehicle in reverse gear. When used on trucks, the transducer is removably mountable to the rear of the truck, with a transmission line lead to the cab of the truck. In the preferred embodiment, a 50 kH.sub.2 transducer is utilized to project a fan beam of radiation from the back of the vehicle so that not only is the closest projecting object in the path of the beam detected and the distance thereto annunciated, any pedestrians or persons having a height commensurate with that of the mounted transducer will cause the range to that person to be annunciated, thereby providing an alarm indication to the driver. In a further embodiment, the transducer is protected from the elements and is either open to the elements only during backing, or is cleaned such that road grime and other hydrocarbons do not contaminate the transducer surface except at such limited times as when the vehicle is in reverse. The audiblization of the distance between the back of the truck and the structure to which it is backed may be provided at a predetermined rate, or may be predicated on a predetermined range change or, may be called out only at preset distances.

Dependencies are inferred from the claim text.