The following car tail circuit was requested by Mr. Danley Sooknanan, it's regarding the designing of a customized car tail light consisting of "running" or chasing LEDs arranged in Yautja language, as viewed in the movie "Predator", over the wrist of the "Alien" being. Let's learn more.....

Technical Specifications


In one of your blogs

https://homemade-circuits.com/2011/12/how-to-make-car-led-chasing-tail-light.html I have question .I want to try the chasing tail lights in my car .

I want to add something to the design I need your help.The turn indicator i want to make it as a predator count down timer.

Let me explain the design in the predator count down timer their is a bunch of sequential lighting. Now what i want to do is have the indicator led move from one point to the other with the predator pattern of the the count down timer.

I would be grateful if you can help me .The other project I am thinking about is a Audio Spectrum Analyzer how i want to do this is place it on the led on the grille .

When the music plays the led moves upwards and downwards when the different frequency is played

Can you help me with the diagram n listing of the parts I need. It is been for years I have wanted to do this project but I dont know who to ask for the help on the circuit design .

Now i am greatful for the effort n time u help others with .

Thanks a million....

before i forget the predator turn signal the sequential count down mus be a little faster than the video i send you move from one point to the other then all the led will flash n light and the the sequential count down starts again

Please provide me with the exact pattern of the LEDs in lit position for the different sequences. you may send me the drawing of it so that I can understand how the LEDs should be laid down.

Regards.

 



Once again Thanks for the reply . I am really excited of this project .Looking foward to your reply.......

I think I have understood your requirement, the sequence will keep only one block illuminated at a time while sequencing.

After the five sequences are over, all the blocks with the relevant patterns will illuminate together and flash.

I hope this is what is required by you.2 by 13 inches will be enough for the design, however the display will not be understandable from a certain distance may be from 30 feet away.

I'll inform you when it's posted.

Good point " the  display will not be understandable from a certain distance may be from 30 feet away."

U know i was thinking about that before i read the email.Here is what we can do to tweak this. After the five  sequences are over the   chasing
light patterns comes on the indicator. then the five sequence.............

With this tweak the driver behind can see that the indicator is on .

Thanks a million looking foward to the post .

Here is the mazda 323 tail light .

I tried my hand on a photo editing software

Now this is the concept .In the above After the five sequences are over the chasing light pattern starts then the five sequence ...................

I would have have showed u each of the sequence predator pattern photo but that would take five more pics to do that .I think u understand the concept

 




If the LED PCB is put over the indicator area, it will block the actual bulb indicator lights of the car because the PCB will be opaque by nature.

How the Sequencing Needs to be Like


About the sequencing: when the blocks light up one by one (the previous block shutting-of as the sequence proceeds), the various lines (signs) present on each block will not make any action, the illuminated pattern will remain fixed on each block as the sequence proceeds....is it that way???

Sequencing Pattern


I googled n got information about retro fitting the taillight .My tail light has bulbs.The idea is to convert the whole tail light to led (LED PCB)

Now this project is all new to me I just have the ideas.What i want to do I want the chasing light feature as your diagram

Now all we are tweaking is the indicator .The indicator part will be converted to the LED PCB

Now this is the concept .In the above After the five sequences are over the chasing light pattern starts then the five sequence pattern...................

 



I just have ideas what do u think is the best way to display this on the tail light

The predator countdown has an awesome display.here are the examples....

I was thinking of the indicator do u think it would be better on the red part of the tail light.Your input would be highly appreciated ............ Now everything is clear, ......one last question though, I couldn't follow this statement of yours:"

After the five sequences are over the chasing light pattern starts then the five sequence pattern..................."

What I understood is, the predator signs would be displayed initially in the chasing pattern.....once this chasing gets over, all the sign-blocks would illuminate together and flash, may be twice and thrice.......what next?? what should be the function after this??

Using White LEDs instead of Red


I think the white section would produce better results.....under the red lens, the red LEDs would become too much responsive, and therefore difficult to distinguish.

I'm really glad that ur taking your time to understand and email me back .I'm am truly thankful.

What i meant in the quote after the five sequences are over chasing light pattern starts then the sequence pattern

It is like a cycle or loop?

Understanding the Chasing Pattern of the LEDs


The predator signs would be displayed initially in the chasing pattern.....once this chasing gets over, all the sign-blocks would illuminate together and flash, may be twice and thrice"

Then the predator sign chasing pattern would start all over again. after it it is over all the sign blocks would illuminate together and flash may be twice and thrice then the predator sign chasing pattern.

You understand now a loop Now we are using this circuit for the red part of the lens on the tailight

Thank you!This project is interesting, and the folks will love to read it when it gets published :)

We had discussed earlier, that the signs wouldn't be understandable from some distance and therefore after the initial sequences are over the background light should start flashing in order to make the light distinguishable to the distant vehicles.....

so I was actually referring to this operation, when should this happen? According to me after the sequencing and the flashing of the predator signs finish, the background lights should come into action.

If the predator sign sequences keep repeating, it will interfere with the actual flashing of the background lights. Since the operations are connected with signalling and safety issues, it needs to be taken care of seriously. This is what I was interested to know about, so it is the last part of the confusion.....:)

Okay good that you mention safety, lets do it with your method then ." According to me after the sequencing and the flashing of the predator signs finish, the background lights should come into action." so it is a loop cycle - predator signs-backround lights come into action - predator signs

This is just like a send u with the last email with all the pics

I'll do it soon, and inform you when it's published....Thanks! Great looking foward to the post .I have some great ideas for some other projects.like a spectrum analyser display for a car.

an antiteft device for a car

Designing the Predator LED Tail Light Circuit


As shown in the following circuit diagram, three numbers of IC 4017 have been used for implementing the required sequencing operations of the predator signs as well as the background LED indicator bars.

The different stages of the circuit operation may be understood with these points:

When the turn signal switch is turned ON, the 12V supply passes through the 7812 voltage regulated IC and powers the preceding electronic circuit stages.

N1 along with R1 and C1 forms the clock generator or the oscillator circuit which provides the necessary clocking to pin#14 of IC1 and IC2.

IC1 outputs immediately start sequencing in response to the above clocks.

The sequencing initiates from pin#3 of IC1 to pin#10 Since the predator LED patterns are connected with these outputs via transistor drivers, all of these signs become illuminated one after the other in the given sequence.

At pin#10 the last predator pattern illuminates. In the following sequences, pin#1, 5 6 and 9 of IC1 become high one after the other....however since these outputs are connected to the base of T1 (see next figure), T1 switches ON and it also switches ON T2.

T2 now starts providing 12V to all the driver transistors which are responsible for sequencing the predator signs, this action immediately switch ON all the predator signs together.
However the clocks (positive) reaching the base of T2 via D1 forces it to blink with every positive clock from N1.

Due to this operation T2 switches in a flashing mode and initiates a flashing response over all the predator which flash thrice until the sequence reaches pin#11 of IC1.

At this point the logic high from pin11 connects with pin 13 of IC1, locking its sequencing on the spot so that the IC now is unable to sequence any further and gets latched at this position.

But the above logic high prompt the output of N4 to go low, which immediately enables IC2 to begin its own sequencing  shifts.

The outputs of IC2 now begins sequencing and illuminates the connected LEDs from pin#3 to pin#11.

This sequencing starts repeating, and in the process the logic high at pin#3 of IC2 clocks IC#3 pin#14.

IC3 responds to these clocks and in turn allows its outputs to sequence. When its output sequence reaches at pin#5, the entire system RESETs, because the logic high from pin#5 of IC3 hits pin#15 of IC1.

The entire process begins all over again.

The outputs of IC2 are arranged as small vertical bars using high bright RED LEDs and are put in between the predator sign-block gaps and ahead.

When the predator sign stops, these bars take their position and continue the sequencing so that the indications become prominently visible even to the distant vehicles at the rear.

 
Wiring the Predator Sign LED Pattern


The following figure shows the method in which the bars of the predator sign may be wired using 3mm high bright red LEDs.

As shown, each of the lines in the signs are made by aligning three 3mm LEDs in series. Once all the lines are aligned with the LEDs, the anodes of each string should be connected with individual current limiting resistors.

The ends of the resistors should be made into a common for different blocks and these points should be connected to the collectors of T3, T4, T5, T6, T7 respectively.

The cathodes of all the LEDs in the blocks should be made into a single common point and connected to ground.

 



 



Parts List

R1 = 100 pot
R2 = 1M
R3....R12 = 1K
R13...R22 = 150 Ohms
R23....R31 = 1K
D1.....D5 = 1N4148
IC1,2,3 = 4017
IC4 = 7812
N1....N4 = 4093
T1 = BC547
T2 = BC557
T3....T7 = 8050
C1....C4 = 1uF/25V non polar

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