Sequential (CHASE) Turn Signals

[MRupp]

Hello Everyone,

I am working on a project for my car. I would like to make some sequential (also known as chase) turn signals. I have looked around on the internet and saw some people that already sell "Kits", but the catch here is that their kits control all three tail lights as brake lights and turn signals. I am only only trying to control two of the three lights as brake lights and then all three as a turn signal.

I have contacted these guys as well as some other companies and they do not want to modify what their current desing to make a new one. So I am stuck trying to figure out how/who can do this.

I have custom circuit boards that I made for LEDs to replace the Halogen bulbs so I can do some modifications to those boards if need be.

The running lights, the brake lights and the turn signals all have their own wire.

Here is the basics of what I am looking to accomplish.

Turning:

I would need the running lights to be on (under normal use) and as soon as the turn signals are applied, the module would shut down power to the running lights AND brake lights to allow for the sequential or chase turn signals that would now power the two brake lights as well as the turn signal.

Braking:

Would it be possible to have a setting for:
1. If the running lights are on and the brakes are then applied, it does not do the chase pattern. The brakes act normal.

2. And if the running lights are on and the brakes are applied than it does a single chase pattern and then return to being bright on just the two inside brake lights?

If having #2. is entirely too complicated than I wouldn't mind just having the brakes do their normal routine which is to just make the running lights brighter.

Here is a picture/illustration of what I would like the tail lights to do.
**broken link removed**



Thank you guys for even looking. I hope someone can help. I would love to see these on my car.

 

[SABorn]

All very simple if you use a micro controller, then basically and combination of logic can be applied to generate what ever pattern you want.

It can all be done using 4 inputs and 6 outputs with mosfets drivers on the outputs.
That would be inputs for brake, tail light, left turn, right turn and an output for each light left and right.

If it was me i would use a Picaxe micro as they are very simple to program and use, with good (other) forum support but not well excepted on this forum.

Not sure what the legal obligations are for this style of lighting in your area, as it would not pass where i am as turn indicators need to be Yellow.

I like the effect but the law would not around here.

Pete.

 

[MRupp]

Hey Pete,

These are for a "show car." However, with red turn signals in mind, I have seen quite a few brand new cars with red turn signals.

I am sure I can learn how to use that programmer, but I would need the circuitry to build the module.

Thank you Pete

 

[SABorn]

As i get growled at if i discuss picaxe on this forum, send me a PM with an contact email address and i will discuss this further off forum.

If you wish to use a different type of circuit than by all means stay on this forum, as there is some very clever people here.

Pete.

 

[ericgibbs]

As i get growled at if i discuss picaxe on this forum, send me a PM with an contact email address and i will discuss this further off forum.

If you wish to use a different type of circuit than by all means stay on this forum, as there is some very clever people here.

Pete.

Hi Pete,
I am sure other members would like to see projects done in Picaxe on this Forum, let the growlers growl...

 

[MRupp]

As i get growled at if i discuss picaxe on this forum, send me a PM with an contact email address and i will discuss this further off forum.

If you wish to use a different type of circuit than by all means stay on this forum, as there is some very clever people here.

Pete.

Hello Pete,

I am open to any kind of design. Really the only major concern is the size of the board/module and controlling in the fashion I mentioned in my first post.

Hi Pete,
I am sure other members would like to see projects done in Picaxe on this Forum, let the growlers growl...

If anyone has an idea about how to do this, please do not hesitate to post it here.

 

[SABorn]

Hi Eric,

I dont understand why this forum dislikes the picaxe chip as its a wonderful stepping stone to cut ones teeth into micro controllers and so simple to use.

I have been asked not to discuss the picaxe on this forum and is why i often help others off forum with a project, i personally would rather keep thing on a forum so all can learn and follow in the footsteps.

But i also need to walk the fine line of keeping the power to be happy too.

I know the raw pic is a much better chip than the picaxe but there is room for both in my world, and some applications we only need a simple to use chip and where speed is not an issue.

I see so many circuits here with a mess of chips cobbled together to do a simple function that a single picaxe could do so easy within program that i wonder why it is not used more often.

I will have a chat with the OP and see if we do this on forum, as well as what other comments are received about my comments here.

Pete.

 

[crutschow]

I have been asked not to discuss the picaxe on this forum and is why i often help others off forum with a project, i personally would rather keep thing on a forum so all can learn and follow in the footsteps.

It may be related to a sponsor(s) of this forum wanting restrictions on the discussion of competing devices.

But I believe such restrictions have no place on this, or any other public forum.

 

[carbonzit]

All very simple if you use a micro controller, then basically and combination of logic can be applied to generate what ever pattern you want.

It can all be done using 4 inputs and 6 outputs with mosfets drivers on the outputs.
That would be inputs for brake, tail light, left turn, right turn and an output for each light left and right.

If it was me i would use a Picaxe micro as they are very simple to program and use, with good (other) forum support but not well excepted on this forum

Not to knock your response (and I would be curious to see what a Picaxe solution would be, damn the growlers!), but couldn't this pretty easily be constructed with discrete logic components? Doesn't sound too complicated, though I haven't even sketched anything on the back of an envelope yet ...

 

[MRupp]

Not to knock your response (and I would be curious to see what a Picaxe solution would be, damn the growlers!), but couldn't this pretty easily be constructed with discrete logic components? Doesn't sound too complicated, though I haven't even sketched anything on the back of an envelope yet ...

Did you have a design in mind?

 

[carbonzit]

Did you have a design in mind?

Sorry, no; it just seems that this should be do-able with just ordinary logic building blocks--AND/OR gates, counters, etc. I could be wrong, but it should be a fairly simple device.

 

[MRupp]

Yeah it should be pretty simple. I saw a normal sequential turn signal module in person and there were only like 2 or 3 parts to it.

I have the design/idea/concept in my head, but have no idea how to put it into reality.

 

[SABorn]

Until someone comes up with a way to use discrete components i will continue with a picaxe method.

A simple example of code to control the flash sequence for the lefthand lights would be something like this below.

It will light each light for for 300 milliseconds then move to the next and do the same

The "if then" statement under "main" checks for the condition of the input pinC.1 for a high signal and if so then the program jumps to the sub routine called "left_flash", the "if then" statment in "left_flash" checks for the condition on pinC.1 again for a low signal and if so switches all the lights off and returns back to the "main" routine again.

If pinC.1 is high it will proceed to flash each light in sequence for 300 ms then go back to "left_flash" and check the condition of PinC.1 again and if still high then repeat the sequence again and so forth.

This just an example and there is more "if then " statements needed and more sub routines required to complete the full functions requested. (ie: brake lights etc.)

Pete.

 

[SABorn]

One question i do have that maybe Eric or someone can help with is, there needs to be a driver between the picaxe and led lights to switch the 12v+ to the lights, and the picaxe has 5v logic out.

Normally i would switch ground and save any hassles with feed back from the higher voltage, but with in car use the ground is common to all lights and we need to switch 12v+.

I have several solutions but was wondering what others would recommend for switching 12v+ with 5v logic.

I dont know the current requirements at present per light but would expect it to be no more than 1 amp.

Pete.

 

[ericgibbs]

One question i do have that maybe Eric or someone can help with is, there needs to be a driver between the picaxe and led lights to switch the 12v+ to the lights, and the picaxe has 5v logic out.

Normally i would switch ground and save any hassles with feed back from the higher voltage, but with in car use the ground is common to all lights and we need to switch 12v+.

I have several solutions but was wondering what others would recommend for switching 12v+ with 5v logic.

I dont know the current requirements at present per light but would expect it to be no more than 1 amp.

Pete.

Hi Pete,
The usual way is a series resistor from the 5V pic pin to the base of a transistor and the load [ ie12V lamp] in the collector.
A MOS FET could be used in place of the transistor.

Would you like a circuit.?

EDIT:
Using a P MOSFET, its well over rated for the lamp surge

 

[SABorn]

Thanks Eric,

I was thinking of using a BD681 darlington transistor as they are rated to 4 amp, lamp in rush surge should not be a problem as it is led lights used.

For some reason mosfets and me dont have a good relationship and when used for frequency switching they make better heaters than switches, (i do kinda know why) but in this case the amps should be low and the frequency is slow, so a mosfet should not suffer too bad.

As for the smd device i think it will be beyond the OP to work with that, so will look to through hole components.

I will put together a schematic when time permits so all can check it for bugs.

Pete.

 

[ericgibbs]

Thanks Eric,

I was thinking of using a BD681 darlington transistor as they are rated to 4 amp, lamp in rush surge should not be a problem as it is led lights used.

For some reason mosfets and me dont have a good relationship and when used for frequency switching they make better heaters than switches, (i do kinda know why) but in this case the amps should be low and the frequency is slow, so a mosfet should not suffer too bad.

As for the smd device i think it will be beyond the OP to work with that, so will look to through hole components.

I will put together a schematic when time permits so all can check it for bugs.

Pete.

Pete,
Are you considering switching the low side of the lamp to chassis [0v].??

The BD681 has a high Vsat at around 1A to 2A collector current,of ~ 2.5V

 

[SABorn]

Hi Eric,

I really dont know how the lights are set up and well expect they have a common earth to chassi.
If this is correct than it will be required to switch 12v+.

I was thinking collector to 12v+, emitter to led light, and a resistor between base and picaxe.

I also dont know how the leds are configured in each light but would expect only a supply of around 2 volts through the light, so i would expect the transistor to switch on fully as the base voltage (5v) is higher than the load voltage required.

Correct me if i am thinking wrong here.

Pete.

 

[ericgibbs]

Hi Eric,

I really dont know how the lights are set up and well expect they have a common earth to chassi.
If this is correct than it will be required to switch 12v+.
If this is the case, a high side switch will be required, [ as per the FET dwg]

I was thinking collector to 12v+, emitter to led light, and a resistor between base and picaxe.
The max voltage across the LED would be 5V-Vbe drop, if a darlington was used the Vbe would be ~ 1.4V, si if I follow your description correctly, all you would get across the led would be 3.6V

I also dont know how the leds are configured in each light but would expect only a supply of around 2 volts through the light, so i would expect the transistor to switch on fully as the base voltage (5v) is higher than the load voltage required.
As its an emitter follower the BD transistor would not saturate.
Correct me if i am thinking wrong here.

Pete.

Pete.
I am not pushing the P MOS approach, but there are T220 pin types available for about 67Pence UK, see d/s.

EDIT:
Dwg, is this the way you meant.??

 

[SABorn]

Hi Eric,

I dont mind using mosfets as long as i know they will work with the correct circuit lay out and is why i asked to start with.
Most projects to late i have used a transistor with good results but a fet is fine just i dont have a good knowledge of them.

The transistor circuit you drew was not quite what i was thinking, as you have a darlington arrangement and i was thinking a darlington transistor.
Here is a general schematic of the full circuit but some resistor values were plucked out the air as a ball park and will need to be calculated further.

I expect the leds to be set up for 12 volt so it shows no limiting resistor for them.

It is just a quick schematic and not the finished project.

Pete.