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Patented, NHTSA-Approved Smart Turn Signal System For Cars & Trucks

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  How Does INTELLITURN Work?

To summarize how INTELLITURN works is to say that it works LIKE MAGIC.  More specifically and more technically speaking, it is described as follows:

Instead of using a bulky and complex mechanism imbedded in the steering column, IntelliTurn uses a deceptively simple method of collecting the signals from two wheel speed sensors to “map” the travel path of the vehicle with sensor differential data.  It all starts the moment the driver depresses the turn signal lever to signal an intention to make a turn.  From that point, the left and right wheel speed signals are compared and accumulated in a computer.  With the continuous data stream from these existing vehicle sensors, IntelliTurn computes the following:                                                        

·        Steering System Position

·        Acceleration

·        Steering Wheel Rotation

·        Deceleration

·        Arc Turn Radius

·        Velocity

·        G’s – Lateral

·        Distance

·        Yaw – Cumulative

·        Time

·        Yaw Rate


As you can see, the data from just two sensors provides highly pertinent turn signal related data and does it with exceptional accuracy.  A time and space “surface map” is constructed in the computer to precisely decide on a situation appropriate shut-off point for the turn signal.  The high precision components are already installed in the vehicle as part of the ABS system.  INTELLITURN expands the usefulness of these components to create a high performance turn signal.

The IntelliTurn driver’s stalk switch itself is quite simple.  It consists of a momentary contact switch design with return-to-center for left turn and for right turn.  A single “cancel” button on the stalk instantly resets any and all functions to “off”.  For a right turn, move the switch lever up with a touch for less than one second duration and the intelligent automatic shut off function mode right turn is activated.  For a right lane change, hold the switch for greater than one second duration and the lane-change mode keeps the turn signal on until the driver releases the switch, shutting off the turn signal.  Of course, left turns work in a similar manner.  The cancel button is always presented in the same position to the driver, so no more looking and fumbling to manually cancel the turn signal.  In fact, IntelliTurn’s high precision function ensures that the cancel button is rarely used.  For vehicles where a cancel button is not practical, cancel would consist of depressing the "opposite" input.  For example if the right turn signal is on and the driver wishes to cancel it, the "left" function is selected.  This makes for a very simple switch configuration.  Overall, the IntelliTurn switch function is a significant ergonomic improvement that driver’s of all skill levels quite naturally and immediately adapt to.       Click here for full color pdf system diagram.

The result is an intelligent turn signal control system that works like magic.  Stays on when it is supposed to, and shuts off when it needs to.  This system is computer programmed to be error free, every time, and all with no moving parts. 

By utilizing existing vehicle computers and sensors, and eliminating the mechanism, this is indeed a high performance, smart turn signal system that approaches perfection.  The manufacturer saves the cost of the turn signal mechanism as well as high count wiring and its associated cost.  At the same time, the consumer benefits from an upscale, value-added, leading edge feature that truly enhances the driving experience, every time the vehicle is driven, and for the life of the vehicle.

In the case of Class 8 Semi trucks, Intelliturn allows for the first time ever, a truly functional self-cancel turn signal that works with or without a trailer.

Hopefully you can see how an intelligent turn signal can work like magic, now for a more in depth explanation of how INTELLITURN works, look at the Math Behind the Magic


©2008 RLP Engineering
Dayton, Ohio, USA