my truck camper

[OP827]

About cable lift systems in North American popular popup tent trailers.
I agree with you 100%.Their design is inherently inferior due to overloaded cables, lifting screw and, on top of all, the cable system is located outside and subject to all elements. It is designed to fail at some point.
I understand why they fail on so many trailers, failing to close or to lift. I am confident that a good and reliable cable system can be made for a trailer. Australian Kimberley Karavans seem to have a good record.
BTW air crafts were using cable systems a lot and small ones still do.

In the end we all choose the system that we feel good about for our builds, this is the advantage of DIY.
Cheers!

[KCStudly]

I have two small linear actuators for my hatch. The particular model has potentiometers built in with extra wires so they are able to provide position feedback. I was able to find a controller that will synchronize and/or operate multiple actuators in stages (i.e. two steps). It also has the ability to store two separate preset positions, along with sensing a blocked operator and returning to the previous preset. The controllers are marketed for custom car applications where they sometimes automate door, hood, trunk and/or whatever they want to operate.

I'd have to look back at my build thread to recall the specifics.

[Philip]

I have been threw your build thread KC. The actuators I am looking at do not have pots. Just set speed of movement. The type with the pots in an industry app would have a variable speed controller hooked to them. Use the pot signal and have a driver board to set speed of movement threw the range of motion. By that I mean start up at slow speed, increase speed middle of travel, slow down before stop point. They used that type in robotics a lot. The small home built CNC market us this tech.

OP8 start pricing quality cables, rollers, tension devices and all the items to make a good manual lift system. Then add in time required to design and build into the item. All those items added together would be more than the price of a actuator system. For a large scale production item it could be done. For a one off item like mine. Just not worth the effort.

[OP827]

Philip,
Have you seen this Landrover conversion to a folding roof camper?

https://s-media-cache-ak0.pinimg.com/originals/d2/79/69/d27969f487139cd3fbfa31f1f8d5bc69.jpg
https://s-media-cache-ak0.pinimg.com/originals/dc/07/d8/dc07d89a6192dbc39426db88d863d7a2.jpg
https://s-media-cache-ak0.pinimg.com/736x/5b/e8/e3/5be8e39e9613f2331e75385858bbc4c5.jpg

What do you think of it?

[Philip]

Philip,
Have you seen this Landrover conversion to a folding roof camper?

What do you think of it?

The one issue I could think about is weather sealing on that design. When its closed thats easy. When its up how good could it be sealed up. The camper I am building is going to used. There are times we might be on the road 30 or more days. I don't need something that leaks when setup.

[Philip]

Here is the next version of this thing.












I like this version better. That dormer didn't look right. Thanks for helping me see the light.

[OP827]

Are you going to add hard walls to the popup part or you are thinking of tent walls? The shape looks nice, btw.

[Philip]

I am still thinking on that one. I would like hard panels mounted on hinges to swing down. With linear actuators that can't happen due to mounting inside the living area.

I am currently running over a scissors setup for lifting in my mind. Those would mount on the flat flange around the living area. That would allow for hard panels.

I do have an upholstery machine and I know how to use it. So canvas will happen if I can't figure out a lift system for hard panel usage.

[OP827]

You could still use actuators and hard walls, see a little sketch below. Google Esterel Caravan or Gobur Caravan to see for yourself about how such weatherstripping is done around hinged areas and panels. It is a time proven concept. What is new here in this sketch is how it is configured for your camper roof and actuators added to the side walls right where the back and front panels end in folded position. What do you think about it?

[Philip]

I am jealous. I have problems drawing a straight line with a ruler. Forget about the 3D programs. I haven't found one yet I can get anything made even close to what I am thinking.

Nice design. The biggest problem is the side walls. Your showing fixed bottom and sliders on the top. The opening on the top of the camper is not going to be wide enough to allow both sides to lay down in the closed position. With measurements I have taken on the flatbed. That top opening is only going to be around 40". I am wanting 24" of lift. So total width on the doors laying flat would be 48". The angled in sides of the camper will determine the top opening. Those angled sides end where to the outer storage areas end inside the camper. I am playing a balancing game here. Even tho my truck is diesel powered. It is touchy to wind drag. If I straighten out the angled section to widen the top opening it throws a lot more profile into the wind. But when I get far enough to have the top basic frame done. I am going to do some mockup on this design and see where it leads to.

Now here is what I am thinking of. I stole this pic from boll-rig a member on EXP.



I would do a little redesign on this. The full cross tubes on the lift part is not needed. No reason to tie both linear actuators together. They are stand alone devises. You just need to make sure all the mountings are in the same position on both sides. I would change to square tube, round tube bends to easy. This system holds all the wind loads the top will encounter. This top has longer arms than what I would need. He is lifting around 36". So I would be using smaller, shorter actuators. This package I could fit into about 2" of width space. With the panels hinged off the top I could make the doors different heights. That would make the mounting points different in the top. That would allow the doors to overlap when folded up. The long sides would have a slide in notch the end walls would fit into to provide a weather seal.

I sure wish I could draw.

[KCStudly]

So if the hard sides hinge down from the top that means that the lift bars and actuators are outside when the top is up(?). Sure would be nice to have them be inside out of the weather (although they are pretty rugged).

[Philip]

So if the hard sides hinge down from the top that means that the lift bars and actuators are outside when the top is up(?). Sure would be nice to have them be inside out of the weather (although they are pretty rugged).

Yes they would be outside. I would prefer inside. To do that means going canvas sides, not wanting canvas unless its the last resort.

The actuators I am looking at are the mini round ones. Those are pretty water proof and small. I could also slide them inside a tube and seal it somewhat. They only measure 1.25" in dia. no offset gear box on them. Can also get them in custom lengths and force output.

[Philip]

My sister and BIL were up a couple of weeks ago to visit. He worked in the fiberglass industry for 42 years. We had a few good long talks about doing glass work. Before they left he told me he would send a few items I could use. I hit the jack pot.

[OP827]

Philip, your roof size seems to be small enough so that it could be made to be easily liftable by hand with simple devices.
Foam sandwich structure is the best way to achieve that.
Manual lifting mechanism can be made as in this video ( https://youtu.be/MCXLYHYj47c?t=53 ), I also saw it in several other diy campers on the net. Four Wheel campers use that as well for over the cabin, bigger roof than yours.
Sometimes, simplier means better and less complex and more reliable system. I do not know about you, but I sometimes get trapped into over thinking something that may have a simple solution. How heavy you think your roof will be? My build sandwich roof piece, which is perhaps 4 times bigger than yours was in a range of 60lbs, without attached side walls.

BTW, my suggested design sketch above may still be optimized to work for your dimensions, geometry of track needs to change from straigh to two pieces that incline from enges to a centre. I can do another sketch if you are interested to pursue the design path I suggested.

Cheers,
Oleg

[OP827]

Hard sides and actuators inside are possible with adaptation of this idea of folding roof and walls -

More pictures and info on that camper is here- http://www.messynessychic.com/2015/06/30/the-fantastic-folding-mini-motel-caravan/