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Industrial Designer needs help - car remote control

Industrial Designer needs help - car remote control

Industrial Designer needs help - car remote control

(OP)
Hello all,

I am an Industrial Designer, I design consumer products for a living. Sorry my questions may appear silly!

I am working on a small remote for car locks for a client. Users need to be able to program it (the same way one programs a 2nd set of car keys, by pushing buttons at correct intervals etc) to be able to unlock/lock their car's doors.

Questions:

Is this possible?

1)
Do I need to get specific information from car manufacturers (frequency, signals..) ?

2)
Are all car remotes working the same way? I don't believe I can program a GM key to open a Dodge vehicle, or am I wrong?


Thank you for your input.



 

RE: Industrial Designer needs help - car remote control

Your underlying question is unclear.  Are you trying to duplicate an OEM remote, or come up with a universal remote?

If so, the yes, you'll probably need to work VERY closely with the OEM.  It's unlikely that any OEM would have frequency or codes similar to anyone else's since that would lead to interference.

TTFN
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RE: Industrial Designer needs help - car remote control

(OP)
I am trying to create a universal remote.

I understand that each car manufacturer uses a different frequency / codes.

Could user plug it into their PC and download the appropriate data? Or is this not something that can be simply programmed?

 

RE: Industrial Designer needs help - car remote control

I'm confused.  You're trying to design a universal remote, yet you know nothing about even your own car remotes?  Do you see a USB port anywhere on your own remotes?

TTFN
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RE: Industrial Designer needs help - car remote control

(OP)
IRStuff

You are correct, I know nothing about electrical engineering and electronic car keys. The product I am working on is not your typical electric keyfob.

A USB port, or other form of connection to a computer, could theoretically be added, if needed, to program the remote to work with a specific car.

 

RE: Industrial Designer needs help - car remote control

If you don't have the memory available on your device then you obviously need to connect to a computer or other device to pull in the necessary codes as needed.
Thats how my logitech universal remote works.. They obviously don't want to fill up the memory with every command for every manufacturer out there so you connect it via a usb cable and select your devices then it uploads the necessary codes to the remote and away you go.

You've got a lot of work to do... Many have multiple security features built in/rfid chips,serialization,etc..nowadays. I hope you quoted high enough for this project...

RE: Industrial Designer needs help - car remote control

My 10 year old Ford F-150 does this...  Look there??

RE: Industrial Designer needs help - car remote control

(OP)
mcgyvr:

Thanks. Regarding the codes (for car locks) do you know if they're available, and how tough it would be to get them? As far as I know, thiefs would have no use for these codes, since it takes a 2nd key to program it.


MiketheEngineer:

Sorry, what do you mean? Your Ford came with a programmable key..?

RE: Industrial Designer needs help - car remote control

If we're simply talking about car lock remotes, the vast majority of them (these days, anyway) use one of only a couple of chips on the market... I think Microchip has the bulk of the market.  You'll need to sign an NDA with Microchip to get the code sequence algorithm.

If you're talking about the fobs for limiting access to starting a car, now you're getting into a more serious area, and I doubt you would see much cooperation from the major dealers.



Why is an industrial designer trying to handle the electrical and firmware design of a keyfob?

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Industrial Designer needs help - car remote control

You could setup a receiver/oscilloscope and 'play' every kind of keyfob to it so you see what their formats are.  Then build a receiver into your fob that just records the owner's key and plays it back thru a transmitter.  Skip the whole USB thing.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Industrial Designer needs help - car remote control

The Man In The Middle attack, recording the output of a keyfob and later duplicating it, would have worked, before rolling codes were introduced.  ... quite a while ago.

 

Mike Halloran
Pembroke Pines, FL, USA

RE: Industrial Designer needs help - car remote control

(OP)
MacGyver:

Thanks a lot, that's valuable information. Yes I am talking about the simple car lock remotes, NOT remote-starting fobs etc..

To answer your question, I am a bit different in that I don't necessarily complete set tasks/goals for clients. I usually set up entire product lines and brands for clients who give me relatively free rein.


itsmoked:

If feasible/reliable, this could be an excellent alternative. My product is quite small, however, so this receiver/chip would have to be small as well. Is this something Microchip manufactures?

I agree that using USB / cables is a bad idea. Forcing end-users to get involved leads to higher rates of rejection / refunds.
 

RE: Industrial Designer needs help - car remote control

NO - I was addressing the codes to get in the door.  The key is a another thing.

Many keys today have an encrypted code that has to "match" the car before starting.

 As a matter of fact many cars don't even have keys.  If you have the "fob" and it can read it - it will start with the push of a button - usually called "START"

Maybe we can have the "fob" put in my wife's arm and she wouldn't loose her "keys!!!!!!

RE: Industrial Designer needs help - car remote control

Ah, but you wouldn't need the WHOLE fob for your wife's arm, just the chip, so it could be in an RFID form factor winky smile

TTFN
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RE: Industrial Designer needs help - car remote control

itsmoked's idea won't work for the reason Mike mentions, rolling codes.  You won't be able to copy someone else's fob directly.  In fact, most of the "programming" of a new remote happens on the car's ECU side of things.  I think if you take a look at the major brands out there, you'll find the majority of them are transmitting the same generic codes already (with a manufacturer-defined ID code attached to it, which is programmed in internal EEPROM), it's just what the car does with them that matters.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Industrial Designer needs help - car remote control

In addition to all the above points (all valid), different remote systems use any of several different frequency bands. So you'll either have N parallel systems (making the key fob that much larger), or you'll travel down the same tortuous path as other Software Defined Radio projects (e.g. JTRS - don't get me started...).

It doesn't matter. The automakers' security considerations alone are the perfect show stopper. The End.
 

RE: Industrial Designer needs help - car remote control

That's what I was thinking VE1BLL a SDR.  I believe Maxim-ic is making a nice one now that is tiny.  I have an NSA acquaintance who loves SDRs.

Now about this "rolling code" do tell.. How's that work?

Keith Cress
kcress - http://www.flaminsystems.com

RE: Industrial Designer needs help - car remote control

They're still working on the SDA* technology, required to fulfill many of the promises made about SDR technology. * Software Defined Antenna - a mythical beast that covers *all* frequencies and applications with one software programmable structure. From HF to microwaves, including a magic LNA to meet all requirements. La la la... smile

SDR technology is fine - if not oversold.


 

RE: Industrial Designer needs help - car remote control

Keith,

It's a linear shift register with a very long rollover period.  The algorithm is designed that even if the fob and car get out of sequence (e.g., pressing the key fob while you're in the middle of the mall and your car is somewhere out in no man's land because it's Christmas and the frikkin' mall owner thinks it's okay to open up a slush lot 5 miles down the road and... wait, where was I?), they will resync within a few keypresses (I believe it's three).  So, if a press doesn't open the door, the typical consumer will press a few more times anyway, and it eventually catches up.
 

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Industrial Designer needs help - car remote control

(OP)
Thank you all.

It seems like there are a number of variables. From what I understand from your comments, it would be impossible, or very difficult, to make out item compatible with ALL auto makers. We are thus considering working only with 1 or 2 large car manufacturers to begin with.

All we'd need is the same chip that goes into their keys, and the matching codes from the automaker, and voila.  

RE: Industrial Designer needs help - car remote control

"We are thus considering working only with 1 or 2 large car manufacturers to begin with. "

So, then, what would be the point, since one can usually get replacement fobs directly from the OEMs?

TTFN
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RE: Industrial Designer needs help - car remote control

(OP)
IRstuff

That is right, they could just go out and buy a new fob, but our product is different in a way I can't reveal here unfortunately.


By the way, does anyone know how much a replacement fob costs? I am trying to get an idea of costs for this feature.

Thanks

RE: Industrial Designer needs help - car remote control

Mercedes Benz - on the order of $300. Plus you have to appear at your local dealer in person with ownership documentation and photo ID.

MB key, in addition to RF, also has Infrared LED for localized control of certain features. The e-key (for starting) uses coded 100kHz induction power and coded LED response (rolling codes etc.)

 

RE: Industrial Designer needs help - car remote control

(OP)
Thank you. I was thinking more about the cheap-looking GM/Chrysler Dodge keys (which look like they were made by the same manufacturer).

These key fobs only have buttons for LOCK/UNLOCK; HORN; TRUNK. I can't see how they would cost more than $6 to manufacture, considering the huge volumes in which they are made.

 

RE: Industrial Designer needs help - car remote control

Considering fobs are made in bulk by a number of Chinese manufacturers, I find it hard to believe that anything custom you come up with can compete in price... at best (and that's being very generous) you could create something that cost the same.  Many replacement fobs can be had for $10-$15, and if you really look you can get them for much cheaper (going closer to the source).

The Mercedes fobs may cost that much if you get them directly from Mercedes (and I'm sure most Merc owners do)... and this is what they charge to key the fob to your ECU.  In the end, though, it's simply a sequence of button presses and such on the car and fob to key them to each other.  Nothing special about the fob, AFAIK.

It sounds like you have a solution without a problem.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Industrial Designer needs help - car remote control

(OP)
MacGyverS2000

Concurred, the low-end fobs can't cost more than $10-$15 retail, which translates into a manufacturing cost of $2-$4 max. That is what I am looking for, no fancy functions.


Now the product I am working on is not a key fob, doesn't remotely resemble it, and has other functions. Locking/Unlocking car doors is just a secondary function. You've never seen anything like it:)

 

RE: Industrial Designer needs help - car remote control

Quote:

...Nothing special about the [MB] fob...

Except the remote control side emits both RF and IR. And the RC fob is part of the rather unique electronic key (coded inductive power in, coded IR-LED out).



Various outfits offer aftermarket keys, but the reports vary if they actually work on all models/years.

 

RE: Industrial Designer needs help - car remote control

Geez - and it used to be so easy to "hot-wire" a car.....

RE: Industrial Designer needs help - car remote control

(OP)
[img]http://images.ecn5.com/Customers/1897/images/CarKeys.jpg[/img]

The Mercedes key is far more advanced than what I'm looking for. Many cars are still manufactured with basic/low-end key fobs that just lock/unlock doors. I bet these don't cost more than a few $ to manufacture..

RE: Industrial Designer needs help - car remote control

Best internet price I found for a brand new OEM remote fob for a Ford was ~$75, delivered, a couple of years ago.

Mike Halloran
Pembroke Pines, FL, USA

RE: Industrial Designer needs help - car remote control

Sheesh, Mike, what kind of golden Ford do you have?  Even eBay has certain models for <$5...

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Industrial Designer needs help - car remote control

That was a slightly used 2002 Explorer Eddie Bauer.
Generic/ universal/ used units are far cheaper; the one I bought was the _exact_ correct part.



 

Mike Halloran
Pembroke Pines, FL, USA

RE: Industrial Designer needs help - car remote control

(OP)
Could you elaborate on how "Universal" units function?
Are they really compatible with most cars? How does the user set them up to work with their car?

 

RE: Industrial Designer needs help - car remote control

By "universal" he just means the plastic clamshell doesn't have a Ford symbol on it, may be shaped like a square rather than a USB memory stick, etc.  Operation, as I mentioned earlier, is identical.

Dan - Owner
http://www.Hi-TecDesigns.com

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