detail
home

view the i-b.l.
slideshow

patent summary

Why monitoring only the forward vehicle deceleration with explicit disregard to
intervehicular distance or the probability-of-collision parameter is an i.b.l. advantage.

Our i-b.l. system may look 'low-tech' relative to many of the futuristic collision warning systems on the drawing boards - many of which are patented devices that propose utilizing intervehicular communication, GPS monitoring, and automatic braking and steering. Accordingly, it’s a challenge to observe why simplifying a system and monitoring forward vehicle deceleration with explicit disregard to intervehicular distance or collision probability is a favored alarm-trigger parameter.  But, by eliminating the analytical complexities and the partially subjective interpretations required to establish reliable definitions for likelihood of collision we can offer a somewhat backward solution of just giving the trailing driver the information they really need to avoid a collision – advance notice that the forward traffic is decelerating.  If, until now, the best prior-art device for notifying drivers that the forward car is slowing has been the low-tech brake light, then we propose taking people back to the future and providing them with the next obvious step – notifying drivers when the car in front of the forward car is slowing.  That extra half-second of advance notice gives a driver the best chance to avoid that next accident.

There are two common flaws associated with any alarm system that utilizes intervehicular distance as its main triggering parameter.

Flaw #1. Intervehicular distance is not a good criterion when traffic density varies from moment to moment. If, at 60 mph the recommended intervehicular separation is six vehicles in length, or about 100 feet, what happens when the traffic density is high and the intervehicular distance is less than 100 feet - should the alarm be triggered? We could ask the same question if the intervehicular distance is reduced to 50 feet - should the alarm be triggered? Remember, if there is no 'emergency' and you activate the alarm the driver will either learn to disregard it or will find deminished value in any subsequent alarms. In high-density, high-speed freeway traffic typical around most major cities, vehicles often travel in tandem at separation distance less than 50 feet; on-ramps, off-ramps, and lane-merges are three such common places. Any device with a pre-defined 'proper intervehiclular distance' will often encounter shorter than proper distances which are not emergencies. At these short separation distances, it is even more imperative that a trailing driver be warned when the forward traffic is slowing. If an alarm is triggered early - as distance triggering devices will inevitably do - then no further information can be given to that trailing driver - they'll be driving blind again. I.b.l. is the only system that accounts for this.   At the opposite end of the spectrum, if a short intervehicular distance is used for the proper distance, then when the driver encounters a lower traffic density – perhaps only a few moments later – the alarm will not be triggered until the host vehicle is too close to the stoppage to be of any value to the driver..

Flaw #2. The proper intervehicular distance for an aggressive-minded risk-taking 25 year-old male is not likely to be the same as for his 80-year-old grandfather with failing vision. Even if stopping variables specific to the car model, the tires, or the weather conditions are included parameters for adjusting the intervehicular distance that triggers an alarm, the alarm will not accurately reflect the respective 'probability of collision' for different drivers.  If that 25 year-old is driving his grandfather's vehicle with collision warnings set for him, he will likely disregard them. And, in the reverse scenario, where the grandfather is driving his car, he will likely be warned too late to avoid a crash. Alarms based on average response times become such a compromise that they become of little value for those outside the mean. And if different cars have different predicted colliding times used to trigger their alarms, then as drivers learn the different values for different cars, some may choose to disregard the warnings, rationalizing ‘oh that car has warnings set for old ladies’.

Lastly, it should be remembered that any new device to be used universally by the public must be as intuitive and non-confusing as possible. The standard brake light is one such device; i.b.l hopes to build on its simplicty.

home