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Safety is the Bottom Line

Active Safety:  Prevention of collisions is the sole purpose of the turn signal in the first place

The flashing light vehicle turn signal, invented 72 years ago has the same purpose now as it did then: preventing collisions.   Only now in the U.S., there are an estimated 235 million vehicles on the road, compared to an estimated 33 million vehicles back when the turn signal was first invented.  It can only be concluded that turn signal usage and turn signal accuracy is more important than ever. 

INTELLITURN has the potential to prevent literally millions of accidents in the United States every year.  RLP Engineering data shows that turn signals are used on average approximately once per every mile driven.  In the United States, the total vehicle-miles driven per year is approximately 3 trillion miles.  In an SAE report entitled "Turn Signal Usage Rate Results: A Comprehensive Field Study of 12,000 Observed Turning Vehicles" (SAE 2012-01-0261), turn signal neglect rates for turns was observed at 25%. If we assume that a collision will occur once every 375,000 incidents of turn signal neglect, then the following could be concluded:   INTELLITURN used on a wide scale in all vehicles has the potential to reduce the turn signal neglect rate from 25% down to near zero, therefore INTELLITURN could prevent up to 2 million collisions per year in the U.S. 

Thus,  INTELLITURN could potentially reduce the number of collisions by up to 16.4%!  This is based on an estimated 12 million collisions that occur in the U.S. each year (however, NHTSA estimates that half of these are not reported to police).  The result of this improvement would significantly reduce injury, lives lost, property damage, lost productivity, etc.  NHTSA estimates that multi-vehicle crashes account for 62.6% of all crashes, with single vehicle crashes account for the remainer.  Therefore, based on an annual death rate of approximately 42,000 per year, 26,292 deaths are attributed to multi-vehicle crashes.  If a 16.4% reduction in multi-vehicle deaths occurs due to the projected improvement in turn signal usage, then over 4300 lives could be saved per year.

This estimate does not even include the number of near-miss collisions that occur, which are unreported but likely add up to the tens of millions of occurrences across the country.  Driving remains a privilege, not a right and drivers have a duty to use their turn signals.  This is not a personal choice, just like stopping when the traffic light is red is not a personal choice, it is a right.  Drivers have an obligation to signal intentions.

Another great feature about the potential safety improvement INTELLITURN has to offer is that it adds little or no cost to a vehicle, because the sensors that make it work are already installed on the vehicle. This makes the benefit to cost ratio amongst the highest of any vehicle safety feature.

It could be safely concluded that today's turn signal controls are functionally flawed. They have several defects that would normally be the target of a recall.  They can stay on when they should be off and they can trip off when the driver would not normally expect.  This is an unsafe condition that should be remedied and the technology to accomplish this is at hand on the vehicles today. 


By way of illustration, let's compare turn signals to external brake lights:  After all, external rear brake lights have exactly the same objective as turn signals do:  prevent collisions.  External rear brake lights are simple and effective:  When the driver depresses the brake pedal, the brake lights at the rear of the vehicle come on.  When the driver takes his or her foot off the brake pedal, the brake light is turned off.  This system is automatic and very reliable.  In fact, if the brake light system is anything less than 100% reliable, NHTSA would intervene and force a recall to assure that the system is reliable on a wide scale.  Therefore, 100% reliability is the only acceptable standard.  Now let's look at the reliablility of turn signals.  On the surface, the manufacturer is required to install a turn signal system that is 100% reliable on every vehicle sold in the U.S.  But the turn signal is by no means automatic and drivers can and do neglect the usage of the turn signals millions of times per day.  Therefore, the system is not 100% reliable, but subject to the usage rate of millions of drivers.  If the overall usage rate of drivers is 50%, then the net reliability of the turn signal is only 50%.  If the overall usage rate is 90%, then the net reliability is only 90%.  The turn signal is likely the most unreliable safety system on the vehicle today 

A smart turn signal like INTELLITURN takes most of the "turn signal error" and has the potential to reduce error down to near zero.  We cannot take out the human element and thus the human error completely in our daily turn signal usage, but just as we as a society would not tolerate any brake light system thatt is in error, we should not ignore the error and flawed function that is built into today's mechanical turn signal either:  Turn signals as well as exterior brake lights each serve vital roles in vehicle safety and both should serve drivers and passengers with the highest degree of accuracy possible in order to reduce the risk of a collision.


2008 RLP Engineering
Dayton, Ohio, USA