RLP Engineering is the Home of Award Winning
INTELLITURN, the
Patented, NHTSA-Approved Smart Turn Signal System For Cars & Trucks
 

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Frequently Asked Questions:

Why a new turn signal?  What is wrong with the present method?  Yes, it is true that the current turn signal performs quite well most of the time.  However, it is those unique, yet frequent situations that the turn signal fails to perform as wished and driver intervention is necessary.  It is at those times when a turn signal is erroneous that could cause an accident.  INTELLITURN remedies the flaws of today's mechanical system. The world driving public, after all, deserves a smart turn signal.  Who knows, maybe people will actually use their turn signals more!

If it does so well at turning off the turn signal, then why can't it turn it on in anticipation of a turn?  That would indeed be a great feature, but only the driver in his/her mind knows the intent of the vehicle path ahead, as it should be.  So INTELLITURN only comes on when the driver moves the turn signal lever.  Imagine a vehicle coming  to an intersection with a four way stop:  Only mind reading could anticipate where the driver will go.  INTELLITURN is amazing, but not good enough to read minds!

Then why not turn on the turn signal as the vehicle starts into the turn?  Turn signals are meant to communicate intent,  as in future actions.  If the vehicle is already making a turn, then the intent has already become the action, and it is therefore too late for a turn signal to serve as a communication tool.  Additionally, an "auto-on" system may interpret a "curve in the road" as a "turn" and the turn signals would be coming on at seemingly random times.  This would get very annoying, very fast.  The best approach is to have the driver in command and INTELLITURN is there to accommodate and respond to the driver's wishes and actions.

Aren't there laws regarding the use of turn signals?  In fact, most state laws require the activation of the turn signal a minimum of 100 feet before the turn.  The typical driver will activate the turn signal 300 to 500 feet before a turn.  Again, the purpose is to signal intent before the turn occurs.  With regards to lane changes, most state laws require the use of a turn signal with a lane change as well.

I am not used to a cancel button with turn signals, is this going to be odd?  If you, the driver change your mind about making a turn, and want to manually turn off the turn signal with today's mechanical system, then the manual turn-off action potentially becomes a distraction.  It is a task that requires looking to see if left or right is on, or fumbling to find the current position of the turn signal, moving it in the proper direction towards off, being careful not to bring the lever past center-off and turn on the opposite turn signal, etc.  This is a distracting task, especially if the driver is in traffic congestion or has other distractions.  If you take just one second of attention to shutting off the turn signal while driving at 45 MPH, then the vehicle has traveled 66 feet during this moment of distracted driving.  That could pose a problem and could contribute towards causing an accident.  With a single cancel button, cancel is cancel . . .  period.  Left or right , turn signals are off instantly.  The button is always ready, in the same position every time it is accessed.  There is no fumbling, there is no looking, there is no mistake.  It is indeed very easy to get used to a turn signal cancel button.  It will actually be a rare event that the cancel button is used, because remember, INTELLITURN takes care of itself.

What if the manufacturer does not have room for a cancel button or does not want to radically change the switch design?  A manufacturer can in most cases modify existing switch assembly levers to restrict lever travel and make a left and right momentary switch design.  In that case, to cancel the turn signal, the opposite direction is selected.  For instance, if the right turn signal is on and the driver wishes to cancel the turn signal, then the left position is selected and the right turn signal is turned off.  This method actually reduces costs.

So,  I move the lever for less than a second to turn on the automatic mode, and hold the lever for more than a second for a lane change?  That means that it only has one position for each direction, correct?  Yes, less than a second activates the automatic mode and puts the power of the INTELLITURN computer to work.  Hold for greater than a second and the lane change mode keeps the turn signal on until the lever is released, then shuts it off.   In reality, this is what the driver does with the current system now.  INTELLITURN's duration-selective, bi-modal method is better because the lane change mode is not sensitive to "moving the switch too far" and accidentally latching the turn signal on, as can commonly happen.   This dual mode switch function is a vital part of the patent.  Furthermore, this method of single switch "touch" and "hold" is a common action that most all drivers are accustomed to:  When you tune a radio station, you "touch" the button, when you store a station, you "hold" the same button.  When you use cruise control, you "touch" the resume button to increase the speed by one MPH, when you want to accelerate more than one MPH you "hold" the same switch.  When you want to change the trip odometer mode, you "touch" the button, when you want to reset the odometer to zero, you "hold" the same button. 

What if I am a lane changer that only does one flash of the turn signal?  See, this is where INTELLITURN will actually make you a better driver!  One single quick flash does not constitute a lane change intent turn signal, or at least not a very good one.  If you do let go sooner than one second but you had intended a lane change, then yes, the automatic mode is activated.  If you do not realize that the signal is on, INTELLITURN recognizes this and will simply shut the turn signal off in about 9 seconds or so on the highway, or just about the time it takes to make a gradual lane change anyhow.  If you do want to shut it off right away, you can simply push the cancel button.  A normal lane change would constitute two or more flashes, requiring a typical "more than one second" movement of the switch.  The system should be programmed to always select a minimum of three flashes.  We feel that a minimum of five flashes is ideal.  As a driver, INTELLITURN will cure you of that nasty habit of only holding the turn signal on for one single flash!

What if I turn on the turn signal and then simply keep on going straight & do not make a turn, what will it do?  INTELLITURN is indeed an intelligent system.  The programming establishes when the turn signal was activated, and turns on the turn signal simultaneously.  After a distance of driving straight, the system recognizes that you have not made a turn and you are not slowing down as if to anticipate a turn.  At a reasonable point, somewhere between 700 to 1000 feet, the system deems that the turn signal was erroneous and will simply shut off.  But remember, INTELLITURN is the intelligent turn signal system, so the distance is variable to be situation appropriate.  If, for instance the vehicle starts to slow down at 990 feet, or close to a determination that the turn signal might be erroneous, INTELLITURN would recognize this and keep the turn signal on because a deceleration can be indicative of a turn and wait for a turn.  If the turn does not occur, then it would shut off. 

Sometimes a turn requires a slight turn of the steering wheel, then the steering wheel goes back to straight, but the mechanism is not tripped and my turn signal stays on until I notice it's on and have to manually turn it off.  Would INTELLITURN  recognize this and turn it off?  INTELLITURN is sensitive to the slightest turn of the steering wheel and also monitors the total yaw of the vehicle.  Therefore, with driver activation of the turn signal, the computer would recognize the turn of the steering wheel, the subsequent vehicle yaw that takes place, then the return to straight.  For INTELLITURN, this is enough to be recognized as execution and completion of the turn and would appropriately turn off the turn signal, unlike today's mechanical system.  This turn situation is illustrated in the example section of this website, Turn Type D.

If I am getting on a highway by using a clover leaf entrance ramp, my mechanical turn signal system just stays on because the steering wheel is not turned enough to trip the mechanism.  Then when I merge, I have to click the lever two stops to the opposite turn signal.  How does INTELLITURN handle that situation?  Assume that the right turn signal is turned on to signal the right hand turn entering the cloverleaf turn.  Believe it or not, INTELLITURN is smart enough to recognize that the vehicle is on a clover leaf entrance (3/4 of a turn around or 270 degrees as in a southbound to eastbound right-hand cloverleaf turn, see the Example section of this website, Turn Type B.  INTELLITURN will shut off about halfway through the cloverleaf, in an appropriate fashion.  As you then proceed to merge into the highway traffic flow (essentially a left lane change), you simply put on the appropriate lane change turn signal to signal a merge.

What if my right turn signal is on and I push the left turn signal?  The right turn signal is instantly shut off and the left turn signal is activated.

Another problem with the current mechanical turn signal is this:  I put on the right turn signal, slow down and merge into the right turn lane.  In merging and turning the wheel, sometimes the turn signal will trip off and it has to be re-activated after entering the turn lane.  Will INTELLITURN prevent this early trip?  INTELLITURN will recognize that the the vehicle yawed a few degrees to the right, then back to the left to straighten up in the turn lane.  It is programmed to recognize this as a lane shift and will therefore keep the turn signal on until the true intended right turn is made. What you have described is seen in the Example section of this website, shown as Turn Type E.  Remember, this is an intelligent turn signal, aware of the vehicle dynamics and responds to the driver's inputs, and will therefore keep the turn signal on through the full completion of the turn.

What if the vehicle is stopped at a light for a long time with the turn signal on?  Because the vehicle has not actually made a turn, the turn signal will stay on for as long as needed. The turn signal will only turn off under specific situations, such as: if the turn is executed, or if the car would then drive straight for an extended distance (indicating an erroneous turn signal), or the turn signal is manually cancelled by the driver, or the ignition is turned off.  INTELLITURN waits dutifully and patiently for the appropriate point to shut off.

What if I am stopped at a light with the turn signal on and turn the steering wheel back and forth, will the turn signal trip off as it does with the mechanical system?  No. Remember there is no direct connection of the steering wheel to the turn signal system.  INTELLITURN only reacts to a rolling radius and to a physical turning of the actual vehicle.  Again, this is a system that takes care of itself and knows that even though you are moving the steering wheel, that you have not yet made a turn.  Most drivers have experienced a situation where the turn signal is applied, then just one small movement of the steering wheel at just the right position and it trips off!!  This functional flaw simply cannot happen with INTELLITURN.

What if I turn on the turn signal, then a moment later I forgot if I turned it on or not.  Can I press the turn signal again to indicate the same direction turn and does anything change?  Whenever the turn signal is activated, the computer uses that moment to establish all counters, orientations, etc as the turn signal event baseline.  If the same turn signal is repeated, it simply re-establishes the baseline, the same turn signal lights continue to flash without interruption, no problem.  The system takes care of itself and operates properly.  The turn signal performance is unaffected by this and the entire repeat of the turn signal switch is transparent to the driver.

What if, while the turn signal is on, the wheels skid with the brakes on, or spin under hard acceleration.  Is this going to throw off the computer and make the turn signals shut off at the wrong time?  Since the wheel speed sensors are usually a part of the antilock brake system and/or the traction control system, INTELLITURN is inherently programmed to recognized these tire slip conditions.  If any slip condition is detected, then an error compensating algorithm is enacted and turn signal behavior is still restored when traction is restored, which is usually before the turn is complete.  All this occurs without the driver being made aware.  Turn signal control is maintained as long as wheel control is maintained.  Turn signal control is restored when wheel control is restored.

When the turn signal switch is pressed, how does INTELLITURN know which direction the vehicle is pointed, North, South, East, West, or somewhere in between?  It actually does not know its relative position to the earth, but it does not need to know.  All that is needed to know is that when the driver pressed the turn signal lever, then that moment and the vehicle's straight-ahead position is established.  All turn related information is computed based upon that established beginning position. 

Then why not use GPS to control turn signals?  There are several major problems with using Global Positioning System, or GPS that make that concept not only out of the question, but makes GPS controlled turn signals fail to meet federal safety requirements.  First of all, GPS may take up to a couple of minutes to establish a reading of the minimum three satellite contacts required.  You could jump into your vehicle and drive for a few miles before the turn signals are working properly.  This is a federal safety requirement failure.  Also, if you drove into a parking garage, or into a downtown city location between tall buildings, or in a tunnel, or under dense trees, you could lose the GPS signal and thereby lose turn signal control:  This is unacceptable and is a federal safety requirement failure.  Also, INTELLITURN is literally about 500 times more accurate that a GPS would typically be.  There are further problems with GPS controlled turn signals, but are not worth elaborating on.

Does INTELLITURN meet federal requirements?  Yes, INTELLITURN meets all Federal Motor Vehicle Safety Standards (FMVSS), in particular section 108 relating to vehicle lighting and turn signals.  This has been documented with a formal ruling by the FMVSS in March of 2007.

What is a half flash?  When the mechanical turn signal is tripped off by rotation of the steering wheel, the system is unaware of the turn signal lamp status, on or off at the time of the trip.  There is technically a 50/50 chance of the trip mechanism catching the turn signal lamp in the on mode, thereby creating a partial flash or half flash.  It is not an issue but it is somewhat abrupt.  When INTELLITURN shuts off the turn signal through computer control and computerized flash cycle, the system is programmed to finish out the remaining flash before shutting off.  Again, not a big deal but it is just one more subtle improvement.

What is a turn signal "dead zone"?  The dead zone on the turn signal is where the steering wheel position is such that the turn signal mechanism collides with the shut off cam and will not latch the turn signal on.  You have to physically move the steering wheel in order to allow the turn signal latch to engage.  This simply cannot happen with INTELLITURN because all moving parts and all steering wheel mechanisms are eliminated.

Can anything be done about the turn signal "tick tock"?  It gets annoying, particularly in a quiet luxury car and sitting at a light for a period of time.  You must first realize the history and the function behind the "noise".  The noise is actually the bimetal flasher clicking to make the turn signals cycle on and off.  They have traditionally been inside the passenger compartment, fully audible to the driver to serve as a reminder that the turn signal is on, and because if the mechanism fails to trip the system off, the driver is required to manually shut it off.  One manufacturer in the late 50's thought it would be a great idea to put the flasher under the hood, making for a silent turn signal.  Only one problem . . . .  MANY of those vehicles would drive down the road with the turn signal on for miles and miles, creating numerous complaints.  Since the driver could not hear the turn signal, they would not realize that the automatic mechanism failed to turn it off.  That manufacturer QUICKLY remedied that situation by placing the flasher unit back inside the passenger compartment.  This brings up a great point, however.  The only reason that we need the "tick tock" is that the present system is flawed.  It needs driver intervention some times.  So with INTELLITURN, the "tick tock" noise can still be there if desired, but it is no longer necessary.  A better method to assure the driver of turn signal actuation is to have a totally silent turn signal with a low cost Heads-up display that uses a green light to reflect into the windshield in the drivers field of view.

So the "tick tock" noise is the turn signal flasher module, but what is all of the other random ticking that occurs when I turn the steering wheel with the turn signal on?  This is the mechanism inside of the steering column that is activated to allow the steering shaft cam to trip the mechanism.  Not only does this mechanism add unnecessary noise, but it also alters the tactile feedback of the vehicle steering system because you can actually feel the ticking.  With all of the noise related improvements engineered into vehicles lately, the six decade old turn signal mechanism suddenly sounds loud in comparison.  INTELLITURN has absolutely no noise or tactile interference at the steering wheel when the turn signal is on.  Steering feel and noise remain superb with or without turn signals on.

I read that with INTELLITURN, the turn signal is reset to "off" when the ignition is shut off.  Why would this be important?  It is a small bonus, but indeed the no-moving-parts INTELLITURN system will reset to "off" each time the ignition is shut off.  This is a nice feature if, for instance, you would have a turn signal on in order to go into a parking space, then shut off the ignition with the steering wheel still turned.  In the conventional mechanical system in today's vehicles, when the ignition is turned back on, the turn signals are still in the "turn signal left on" position and will come back on.  This is a nuisance.  In fact, very expensive luxury models, such as the Porsche Cayenne and the Audi A8 have an audible warning beep that comes on if you would leave on the turn signal switch when you are getting out of the vehicle.  The problem is, you have to know why your car is even beeping at you and once you figure it out, you would still have to move the switch to center to get it to stop beeping!!   With INTELLITURN, if you happen to bump the turn signal lever when getting in or out of the vehicle, the system still stays off when the ignition is subsequently turned on.  With INTELLITURN, the turn signal never comes on when the ignition is turned on, nor would it beep at you when you get out of the vehicle.

Since turn signals are a safety item, what about failure modes?  By tying into the ABS system, there is safety and redundancy built in to the system.  For instance, INTELLITURN only needs two sensors to operate, but there are usually four sensors on the vehicle.  If, for example, one of the wheel speed sensors fails, the ABS computer would detect the failure, put on the ABS light at the instrumentation to alert the driver.  As the failure is detected, INTELLITURN would then seamlessly switch the sensing to the other two sensors to detect vehicle dynamics.  The driver would not even know that the turn signal system made the switch because the turn signals would maintain their optimized performance continuously until the failure is corrected. 

If INTELLITURN is better and is more technologically advanced than the mechanical method, then how and why can it potentially cost less?  Even though it uses wheel speed sensors, and a computer, these are devices that are already in place on vehicles equipped with anti-lock brakes.  INTELLITURN uses the same signal feed as the anti-lock brakes.  If the ABS computer or a body computer is used as well, then there is little or no added cost.  At the column switch, the delicate trip mechanism/switch  is totally eliminated and the replacement switch is just a simple momentary switch design each for left, for right, and cancel.  The signal from the drivers switch lever can be multiplexed over two small wires, replacing up to 8 large wires.  Again, a significant cost savings in wiring simplification.  Currently, the flasher module unit is made to be consumer-replaceable with a ready access plug-in point under the dash or with the fuses.  The flasher module and all of its associated wires and harness can now be eliminated, reducing cost further.

Why couldn't a motor or some other device be added to trip the lever to the "off" position and use a computer to control the motor?  Adding some other device to the existing system adds more mechanical complexity, cost, space required and wiring inside the steering column.  Compare this to the INTELLITURN system that has no moving parts, lowers cost, and reduces space and wiring required in the steering column.  INTELLITURN is truly a revolutionary improvement and a fresh way of thinking in the turn signal world.

It sounds as though there may be a weight savings here by eliminating parts, is that the case?  In the motor vehicle world, weight savings is ALWAYS a benefit, all else being equal.  It is not a significant amount, but it is in the right direction:  Elimination of the mechanical trip parts will reduce weight, but not substantially. 

Can this be made as an aftermarket device to be added by the vehicle owner?  It would be highly improbable that INTELLITURN could be an "add-on", simply because it is so different of an approach to turn signal control that the existing mechanical system is somewhat "in the way".  Wiring, computer connections, wheel speed sensor connections, all are integral components of a vehicle's architecture.  INTELLITURN is best integrated into the basic design of the vehicle either at a model change-over or as a new vehicle platform.  This allows for the manufacturer's cost savings to be realized and for the driver to experience optimized turn signal performance. 

If INTELLITURN is best integrated into a vehicle, does the size of the vehicle matter?  Each application is programmed for a particular vehicle, based upon specific parameters.  ALL vehicles, from the smallest micro car to the largest SUV's, trucks and semi's can benefit from this system.

What if a different size of tire is installed, or one tire is low on air as compared to the other tire?  Error compensating software is constantly enabled allowing the system to react in just a few hundred feet to any change in tire status.  Even as a tire is losing air, INTELLITURN is making corrections to keep the turn signal performance in a near perfect operational mode at all times.  New tires installed or a smaller diameter compact spare tire are completely accounted for in the first drive, without any driver intervention.

Could INTELLITURN be made into an option on the vehicle or as part of an option package?  It could be an option if the manufacturer chose to go that way, however, many advantages are lost in this approach:  Two separate turn signal systems would have to be engineered and accounted for in the manufacturing process.  Also, the better system would actually be the less expensive system.  It makes the most sense from a manufacturers bottom line standpoint to make it a standard feature across the vehicle model line:  Maximum cost savings with most satisfied customers.

What about steering wheel thumb-control turn signals, could that feature be an option?  Yes!  With INTELLITURN, all of the components would be there to make a thumb control equipped steering wheel a "plug-n-play" feature, added when the vehicle is assembled.  Since the steering wheel controls are in addition to the turn signal stalk, and the switch wiring is a parallel electrical connection, then this is an easy and highly profitable option with high customer appreciation.  Remember, the steering wheel controls are full function automatic turn signals that operate in both lane change and automatic modes.  This could be a stand-alone option or more likely part of a "steering wheel controls" option package that also includes the sound system controls, HVAC controls, etc.

Since this system is all electronic, and computer controlled, are there any other benefits?  In-vehicle networks, such as CAN or LIN can be tied into the turn signals now.  By tying into the vehicle network, features like a turn anticipator could be designed into a computer controlled suspension:  If the right turn signal is actuated by the driver, then the left rear and the left front suspension damping rates could be altered before the turn to reduce body roll before it even has a chance to occur.  Other vehicle factors may be taken into consideration with turn signals that could make the system even better.  One such programming method would be to automatically have the system recognize highway modes verses city modes.  This is easy to incorporate and could alter some of the timing sequences appropriately.  Remember, once the hardware is in place, the software refinements are relatively simple. 

Does the programming effort have to start from scratch with each new vehicle platform When a manufacturer achieves the system behavior that is considered most ideal over the widest range of conditions, transfer to a different vehicle to duplicate the same performance is a matter of entering the fixed values that would be unique to the new vehicle.  These parameters include Wheelbase length, Track width, Steering ratio, Tire size, and Wheel Speed sensor calibration. 

Is it expected to be more reliable?  Since the system is electronic and there are no moving parts, reliability and therefore quality are expected to be improved.  Never would a flasher module have to be replaced, nor would the manufacturer have to design-in a readily accessible flasher module location.  Manufacturers warranty cost is expected to be greatly reduced.  A life-of-the-vehicle is especially significant for over-the-road semi trucks or buses, where the expected life of the vehicle is usually more than one million miles, and overall fleet costs are reduced. 

 

2008 RLP Engineering
Dayton, Ohio, USA