Patent CA-2102076-A1 (CA)
Title: Safe interval driving signals
Inventor: BARDHAN BIBHUTI B
IPC: B60Q1/46
Filed: 1993-10-29
Abstract: The terms "automobile" or "car" will be used in a generic sense to denote all kinds of motorized vehicles, such as cars, trucks, buses, vans, motorhomes, motorized trailers, motorcycles, motorscooters, etc. for the purpose of the presentation, unless specified otherwise.         When people drive automobiles, it is very important that the automobiles are driven keeping a "safe distance" between one another. One of the definitions of this "safe distance" can be: The minimum distance necessary for an automobile, following another in front, to be able to stop safely and without causing a collision with the automobile in front in case the latter happens to come to a sudden stop at that particular moment.         This "safe distance" is especially important when automobiles are driven at high speed on a busy highway when a collision accident between two automobiles or a sudden stoppage of one vehicle can cause a series of accidents that can be called "multiple accident", "chain reaction accident", "domino effect accident", "serial telescopic accident", etc. etc.. Such dangers become particularly prominent in some inclement weather conditions, such as, .....Pago 2 reduced visibility due to fog, snow, heavy rain, etc. or difficult driving conditions like in the dark at night, etc. etc..       This "safe distance" is computed with various factors, such as, speed of car, breaking efficiency of car (like having power brakes, disc brakes, anti-lock braking system, etc.), weather and other driving conditions (such as, fog, rain, snow, darkness,etc.), lag-time in human reflexes, driver's efficiency, etc.       Highway and other authorities have developed various methods and standards of helping drivers calculate such "safe distances" e.g. to keep between two driving cars a gap of one car-length for every 10 miles per hour of driving speed, markings (such as, 'chevron') on the surface of highways, etc.. However, obviously, these are only very crude methods. Even a conscientious or safety-minded driver may be left with only use of his or her hunches or gut-feelings to figure a out a "safe distance".         this present invention takes away these "hunches" and replaces them with an accurate computerized reading that is constantly and appropriately being updated according to the changing conditions.         Moreover, this present invention not only informs but also alerts (and warns) the drivers who at any time become oblivious of the need for keeping a "safe distance".         Another problem or hazard faced by the driver of an automobile is that often another automobile driving behind may come too close for safety of both.                                                     .....Page 3 In such a condition, this present invention informs, alerts and warns the driver of the automobile behind that his or her automobile is not keeping a "safe distance", in case the other driver is, for any reason, unaware of the dangerous situation. Also, such a "Warning" sign as in this present invention may make even a careless or reckless driver take some proper action subliminally. Similar signals can be given to the driver of an automobile being driven in front as well, in case, for example, that driver can use this information, if necessary possible.                                   .....Page 4