Electronic Geek needed (and ideas)

[Gomjaba]

I am looking for a solution ...

Imagine a truck .. and a trailer (not mine, this one is googled):

http://i32.tinypic.com/r9ek3d.jpg

So, both, truck and trailer have a lot of gizmos (which you don't see on the picture).

The trailer for example has lights etc. and also motorized support legs which can be lowered and liften via the radio. You can also switch on lights etc. etc.

The battery however is in the truck itself. As you can see there is a grey cable leading from the truck to the trailer which is plugged in using a 9 pin

(back of the cabin - the socket is on the right hand side - on the left hand side are just 4 switches)

http://i25.tinypic.com/20jgs37.jpg

It is very nice to have the lights and motorized support legs switchable with the radio ... but it is pretty pointless IMHO if you still have to walk over there in order to connect the ugly cables.

My plan was already to change the cable to something REAL looking. So instead of the electrical cable I intend to use the look of air pipes

http://i30.tinypic.com/2cibczq.jpg

Fair enough ... BUT .. those you have to touch manually already .. even though it would look better.

What I was thinking is some sort of magnetic telescopic something which connects both electrical in some way ....

Hard to explain ... in a way planes get refueled ... or something build into the 5th wheel ..

I have NO idea what I can use / build ...

[Mouton]

I am far from an electronics wizard. But since I am curious I have given this topic some thought as I am interested in getting a trailer myself.

The motorized support legs have their own powersupply on the trailer. They already operate as we all wish they would since they have an activator that feels when they are supposed to operate (when the fitfth wheel is beeing opened/closed).

The LEDs however, need power and signals in some way. The problem is the brake lights, which would require two power levels as to give both tail light and brake light.

Using the air cables (red, white and green) gives three cable and the remaining could be installed in the fifth wheel (preferably by isolating the pin). While this is quite easy to do and will look the part you still need to actually insert the cables yourself.

I see two other paths to go down if you want it all to work hands free:
I would go for this solution; use a second receiver in the trailer that activates when the support legs go up. This could be done with a micro switch installed in the support legs mechanical switch. Such a receiver could duplicate the rear lights,brake lights, backup lights and a bunch of orange position lights (or even an illuminated number plate) at a fair cost. How?, Simply by hooking it up to a Tamiya TLU-02 (http://www.tamiyausa.com/product/item.php?product-id=53937) and a TLU-01 (http://www.tamiyausa.com/product/item.php?product-id=53909). You would need:

TLU-01
TLU-02
An extra receiver for the trailer
A 5 cell AA-battery to feed the receiver and TLUs
Tamiyausa.com has links to the manual. A quick glance thru them indicates that it would work as desired. In other words all this can be done using only Tamiya parts. :Tamiya1:

The expensive route is to investigate Wedico's (are we allowed to curse in church?) solution to the problem. Wedico does have a kit that uses IR to transmitt the commands between the tractor truck and the trailer. Beware though, all such experimenting will void the warranty! The part for the tractor truck is Wedico 790 and for the trailer the part no. is 791. Also worth mentioning is that those Wedic parts cost about 230 dollars, so it is a lot of money for something that is only a start for a solution. It gets even worse when you dig more into it as others say you need Wedico part 796 and 979 instead. Those would set you back a hefty 600 dollars! The problem is to get the Tamiya MFU to talk to the Wedico parts. Wedico operate on 12 V too, which could mean incorrect function or even damage to either part. Another "problem" is that IR can have problems operating correctly in strong sunlight. As you see this is no hands-on solution, but rather a suggesion as to what might work.

[Gomjaba]

Thank you very much for your input Mouton.
It is indeed a very nice idea using the light kits.

I was actually thinking about something else too. I will have to make a few modifications which require an additional power source anyway - preferably 12V .. Since I am building a scaled 53ft trailer, I will have enough room for gizmos like that.

So, in theory, I should be able to use that powersource for the LEDs and the support legs as well ...

This is pretty easy to do ... but then again - I require the signal as well.

But talking about the air cables. My last truck actually had 5 cable going to the trailer (my real one that is). I had (Scania) one yellow cable, one red, and 2 black ones .. the black ones where electrical leads ...

Besides, you can always fit more leads into one cable using tubing ....

But something else came into my mind yesterday .. I am not even sure if I even put the motorized legs in there .. the trailer will be made from scratch and I am not sure whether the legs actually fit ...

Still have enough time to plan :)

[janderson]

Ok, this topic has bothered me for some time now. I do not care for the gray din plug cable and would like to see the possiblilty of disconnecting the trailer vie remote only.

The only to easy ways I could come up with are: (Stolen from 1:1 Cars electronics)

Ever seen those nifty steering wheel controls for radio and cruise controls?

1. The old way the did it was have a plate with a round contact trails so when the wheel turns it still keeps contact. Would require a male brush type contact on trailer to meet up with 5th wheel

2. New way is through infrared you would have a transmitter and receiver that beams signals to the trailer.

Of these two choices

#1 uses no power to run as they are only contacts
#2 would require power for both TX and RX

For #2 please see attached drawing to get a better idea. (sorry for crude drawing)

[mrfish55]

I am working on the same idea as jandersons , photoetch brass contact plates on the fith wheel and spring loaded contact points on the trailer, will post pics when complete and let you all know how it works.

[janderson]

Well it's good to know my idea is not so far out in left field and someone is working in that direction.

I still think the infra red idea would be the best, as it would be clean and wear nicely over time, but would require a lot more technology

[Gomjaba]

Thanks, I thought also about the 5th wheel idea which is, I think, the cleanes and easiest way to do it.
So I could simply create a ciscuit board and screw it onto the 5th wheel ...

But I agree - the infra red version would be the best, but a bit more complicated.

MrFish55, would appreciate to see pictures :)

And janderson, the drawing is very good :) Not crude at all :)

[janderson]

And janderson, the drawing is very good :) Not crude at all :)

Thank, but for me it was way crude, but I wanted to make it easy for people to get the concept :first:

[Mouton]

I have considered jandersons solution too, but I see a problem with placing multiple leads in the fifth wheel. Unless you turn off all lights before hooking up/unhooking the trailer you might short circuit the MFU.

That is why I suggested using only one lead in the fifth wheel. You could use two, one in the peg and the other etched like already suggested. But adding more leads would risk damaging things. That is why I believe in going for a second reciever and the TLU-01 & TLU-02. That requires no etching skills and no further knowledge in electronics as to make sure no damage will be inflicted on the MFU once you short circuit several of its leads.

It would still be doable if you springload all the pins and have them lifted at all times when the fifth wheel is not locked. The springs need to lift the pins beföre you start driving away from the trailer and must not come down untill after you have fully backed up so the peg is in place on the fifth wheel.

[janderson]

Very true, but it would depend on how you setup the pins. You would only be able to back straight in though you could not hook unhook 5th wheel if trailer/rig were not straight

You see ground would always be active so it would be the last to hok up and first to leave

The brake is only really hot right when you hit the brakes, so at the point of unhooking or backing in there should be no voltage to it.

They other lights should not matter as the ground will be gone, so it should not effect if they skip over the traces really.


I see the only real issue is wear from use and corrosion from no use.

I added a few more details of where I would place the pins

[rcgrsemunki]

Hey Janderson,:yourock:
The drawings definately make this idea seem feasible. To simplify mounting, one could even mount thin copper strips into a sheet of lexan and use Tamiya's thin double sided tape to stick it to the fifth wheel. That would avoid having to do any permanent carving in the plastic.
The question I have though is about the spring loaded ball connectors that would mate to this. Would something off the shelf work, or would it have to be built as well?

[janderson]

I would imagine something would have to be built for the contacts. I would like to see what Mr Fish came up with?

[drew6210]

will the http://www.tamiyausa.com/product/item.php?product-id=53937 work with this http://www.tamiyausa.com/product/item.php?product-id=56501

[McFig]

I don't believe so

[Mouton]

drew6210, while it cannot be controlled by the electrical unit you can use the TLU-02 in parallel with the electrical unit. I assume you want to add more lights to your rig? If so, you can do that by adding a TLU-02.

Keep in mind that the TLU uses LEDs that sort of look like HID headlights whereas the electrical unit uses light bulbs, which look more scale on the "older" rigs.