Vehicle: Car: Brake Lights
Wireless Turn and Brake Signals   (-2)  [vote for, against]
No signal light wiring, hitch to a trailer and go!

Every time I borrow or rent a trailer, the $%^# signal light socket doesn't seem to work. That's old school! Time to go wireless! Replace all your car's tail lights with new lights that contain little transmitters built into the base. A pair of LED tail lights with a pair of "C" batteries would be attached magnetically or screwed on to the utility trailer or caravan to be towed. When the car (master) turn signals are activated, the trailer (slave) signals respond in kind. If there were RF interference, the Tx and Rx would automatically search for clear frequencies, just like a cordless phone. Range would be 30'. This could be applied to the car tail lights themselves. No wiring buried deep within the car to go bad! Just cheap, reliable modules. Many other things besides tail lights could use this technology. If we are smart enough, that horrible tangle of wires could largely disappear from cars.
-- bobad, Jul 24 2004

CAN bus http://www.embedded...?articleID=13000304
"A bus architecture is the answer." [half, Oct 04 2004]

http://www.wirelesstowlights.com/ Like these? [jutta, Dec 18 2004]

4,859,982: Wireless Taillight System (1989) http://patft.uspto....982&RS=PN/4,859,982
[jutta, Dec 18 2004]

This might be ok if it were a standard. You're going to have to tap in to that mass of wire somewhere to get to the brake/turn inputs to your transmitter but it could be done once. Maybe the transmitter could be embedded in replacement tail/brake light bulbs.

It would need uniquely coded transmitter/receiver pairs to prevent proximate vehicles from activating your signals or vice versa.

That horrible tangle of wires will soon be gone if certain people have their way (link). I'm in favor of it. "Some modern automobiles contain three miles of cabling" and I've installed a mile or so myself on a couple of occasions.
-- half, Jul 24 2004


[Busy activating the signals on bobad's trailer from the other lane...]
-- DrCurry, Jul 24 2004


// [Busy activating the signals on bobad's trailer from the other lane...] //

Aww come on Doc! We're smart enough to overcome such a miniscule problem! Meanwhile, get off my bumper before I re-boot your car! :)
-- bobad, Jul 24 2004


//tap into that mass of wire somewhere//

For rentals, the lease company can supply a transmitter that clips to your turn signal stalk. It has a small switch lever that presses against the steering column so when you use your car's signal, the tramsmitter is also activated.
-- bpilot, Jul 24 2004


How about a pair of small photoelectric thingies (optical transducers) that stick on the taillight lens of the tow car and send out signals that cause the wireless light receivers on the trailer to mimic whatever the tow car taillights are doing?
-- bristolz, Jul 24 2004


Bristolz: Exactly. Whether optical or RF, the concept is the same: No wiring necessary. Another thing that popped into my mind (actually YOUR mind) was towing a car. All controls on a towed car could be slaved to a master car, and be "towed" driverless. It would need proximity braking, because no 2 cars have identical brake behavior, but everything else should work great.
-- bobad, Jul 25 2004


I was thinking of the optical sensors as well. It would be much simpler for a temporary installation. In that implementation, I had concerns about discriminating between light from the bulb and light from ambient light sources for triggering the transmitter. I didn't think on it long enough to decide whether that would be a significant issue.
-- half, Jul 25 2004


I like it, however several problems... your batteries could go dead on the trailer ( resolve with solar? ) and what about trailers with electronic brakes, they require a tremendous amount of energy to operate
-- shad, Jul 25 2004


With LEDs, a charged battery should operate the system for quite some time. However, in order for this system to be fully viable, some sort of alternator or generator could be turned by wheels of the trailer. This charging system could be used to keep a dedicted battery charged up for the trailer's electrical needs, including electric brakes. Well, we've really got the (snow)ball rolling now.
-- half, Jul 25 2004


// what about trailers with electronic brakes, they require a tremendous amount of energy to operate //

I keep thinking about wind-up brakes. A hundred feet traveled would stores mechanical energy for a burst of braking. When tripped by the brake lights, the brake applies a light, uniform pressure until released. You see, most 5000# and smaller trailers do not need a lot of braking power. They need to augment the towing vehicle's brakes just enough to keep from wearing them out.
-- bobad, Jul 27 2004


bobad, I couldn't disagree with you more

from my experience trailer brakes need to provide enough braking force to nearly lock-up the tires (but hopefully not quite) and hopefully reduce the typical braking distance for the vehicle in an unloaded condition

what normally happens when one is hauling a trailer is this...

some moron is waiting to turn onto the highway they see you and they think < this guy is too close, I should not go >

then you continue to drive until you are close enough that they can see your trailer. then the person thinks < man! this guys got a trailer I bet he is going 25 mph > now, I am traveling at 65mph with a gross trailer weight of 12,000 and this moron, using some sort of horrific judgment, decides that the best thing to do would be to pull right out in front of me.

This guy would be just another one of those marks on the road if I had not been expecting this and had one foot on the brake and I had my trailer brakes freshly adjusted

this is when you need your brakes to work and work well, not have to rely on some radio controlled battery powered device

trailer connections are built to a standard and they have a standard color code and pine configuration.

if the connectors are hooked up correctly all that is necessary to switch between connector types are adapters that are commonly available
-- shad, Jul 30 2004


There's a type of trailer brakes that'd solve your problems. I will try to find a link for it, but basically it uses any deceleration force by the towing vehicle (car goes slower then trailer, trailer pushing on car) to apply brakes on the trailer, until trailer is slower or equal to (in speed) to the car. All in all, I do find the cables a hassle, especially when they get ripped, or wrecked, or whatever.
-- swimr, Jul 30 2004


What I'd like to know is, why are you borrowing all these trailers? Don't you have a friend with a van, like everyone else?
-- Ander, Jul 31 2004


First of all, I would tend to be distrustful of a system that relied upon batteries in a trailer to operate signal lights. If the batteries go dead, the person in the car might not realize it (unless there were a complicated two-way transponder arrangement, in which case things would be so complicated what would be the point).

Secondly, I guess I don't see what's so bad about four wires going to the trailer. Plug one connector and you're good to go. Of course, if you don't have a connector that's wired up you might have some difficulties, but if you don't have a connector that meets the proper standard why would you have a radio that met the proper standard either?

As for braking, I don't see why braking should require any significant energy since the whole purpose of brakes is to absorb energy. The kinetic energy of the vehicle should provide plenty of energy to operate the brakes.
-- supercat, Dec 18 2004



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