Trailer with rear steering axles

[elliot330]

Hi All...

I'm in the process of building a low boy but with steering axles on the trailer. At present I am controlling the trailer axles by a channel on the radio, however, my head is in overload when trying to navigate a corner!

Is there a device that when connected to the 5th wheel/ King pin, that detects an angle between the trailer and 5th wheel, thus operating the rear steer automatically?

Thanks in advance.

[mack kid]

This is one way. you use hydraulic cylinders on the fifth wheel

http://www.youtube.com/watch?feature...&v=qSAlfv6RD34

[PetervR]

you could use a "servotester". their use is to test servos without using radio controll.
and in this case the cheaper the beter. basically the electronics from a servo without the servo.
http://www.youtube.com/watch?v=4N_FXFopjo0
grz PetervR

[elliot330]

Thanks for the ideas guys. I should've said that I already fitted servo's on the rear trailer axles, so need something electronic. The servo tester option looks good. I might see if I can explore that.

Thanks

[dabears]

what about add too rods off the front of the 5th wheel. and on the gooseneck add 2 spring switches, so when the rods hit the switch itll turn the direction you want it too. but when the rod isnt pressing on the switch (almost like an open relay) it'll re center the axle?

[hitachi]

you could use the same channel as the steering of the tractor unit.
many trucks in real life are set up that way when you steer the truck the trailer steers too

[mack kid]

How about y harness for servos so both get same signal.

[elliot330]

Originally Posted by hitachi

you could use the same channel as the steering of the tractor unit.
many trucks in real life are set up that way when you steer the truck the trailer steers too

I tried this to start with... but once the tractor unit has turned the bend its wheel can straighten up, however the trailer still needs its wheels steering to make the bend.

[SmallHaul]

Cables in an "X" pattern would probably work nice. The most important thing is the attachment points on both the back of the truck and the trailers steering have to be the same width so that both cables will be of equal length and tension regardless of how much you turn. One gives while the other one pulls...The cables would be permanently attached to the trailers steering and just have removable hooks on the back of the truck.

[SmallHaul]

One more thing that is important if you try cables..not only does the width have to be the same on both ends but, the pivot point has to be very close on both ends or you would get a lot of slack while turning. I use "pull pull" cables on my large scale airplanes for the rudder. It can be a pain to setup so maybe just play with some string and see if it is feasible.