[WIP] Scania Dunderbygge

[Hrafn]

Now, I would like some help.

I need to control two pneumatic valves on one receiver output. When off, both valves should be in one end position. When forward, one valve should change position. When reverse the other valve should change position. Both should return again when off.

Does this make sense? If not just ask and I will try to clarify.

My mind have been stuck on this for some time now and I would really appreciate any help you could give.

Do the valves have to be in a particular orientation or spatial relationship to one another?

[Saberwing40k]

Now, I would like some help.

I need to control two pneumatic valves on one receiver output. When off, both valves should be in one end position. When forward, one valve should change position. When reverse the other valve should change position. Both should return again when off.

Does this make sense? If not just ask and I will try to clarify.

My mind have been stuck on this for some time now and I would really appreciate any help you could give.

Happy building

Becca

It would help a lot if you specified just what the valves do. So, when the motor is off, you want both valves in neutral, but when the motor is turned one way, one valve is on, and the other remains off, and the other way, the other valve is turned off, and the other on. This will give you two valves, but with control in only one direction each.

This should be easy to implement, I'll mock something up in ldd.

[Zerobricks]

Like I siad I would use a servo motor to control valves on the same port as drive motor...

[Becs]

Thanks for trying to help.

To clarify, both valves should control the same cylinder so that the cylinder is either extended, retracted or free-floating.

It is for the steering of the rearmost axle, if that helps you get the right mindset.

[Becs]

The pneumatic control is starting to give me a headache, and I am waiting on some parts to complete the truck. So I decided to start working on something to transport

I have choosen to build a Gremo 1050h harvester. At the moment I got a simple mockup just to get a feeling for the size.

I know the wheels looks a bit too small, that's because they are. The power puller wheels would be a better match, but I don't have any, and buying eight of them is just too much money

Anyways, the plan is to make it drive and steer remotely via NXT and the crane might get powered via a gearbox and some PF-motors

Happy building

Becca

[unimog123]

This is really cool! By the way how much did all those unimog tires cost? Can't wait to see the finished product!

[Becs]

Glad you like it.

I don't remember how much i paid for them. I got four from the Unimog and then bought eight more from Lego Service.

[unimog123]

I was also wondering what motors you use for steering and drive (and other functions)? Keep up the great work.

[EyesOnly]

That truck looks great. I'm glad i'm not the one building it though. Must be a lot of work building such an enormous model.

[Milan]

Looking forward to next update!

On that scale, studless cabin looks like it is brick built!

[Becs]

Hi everyone

@unimog123: Let's see.. For drive I use 2 L-motors, steering 1 M-motor through a wormgear. I use M-motors for front and rear walking table, support legs, loading ramp and pneumatic compressor. And servos for the pneumatic valves. All powered by a single rechargeable battery box.

@EyesOnly: It is quite a hassle to move it around. There are only two spots where I can lift it whole without risk of breaking parts, I have to take hold of the chassis between the front axles and then grip the trailer connection from underneath and support the trailer on my arm. I try to work as much as I can without moving it, the strain on my arms makes me reluctant to lift it. I have yet to weigh it

@Milan: Yes, it looks that way. On this scale it would just look weird built any other way, besides, I am not used to thinking all the steps ahead required to build "super car style" with panels, flex axles and complex geometries. So much easier just to stack pieces

Progress on the truck has been mostly details, nothing big enough to warrant photos yet. A pneumatic compressor have been built into a "gas tank" to be placed behind the cab. The problem with controlling the valves is also solved, pictures come later in the post.

Regarding the harvester, I am afraid to report a loss of interest in completing it. At the moment it will just be remote controlled steering and driving by NXT.

If anyone is interested in helping me program it and a remote, let me know. I am still a novice on NXT-programming

Here comes some pictures of the valve control.

I have made an LDD-file of it and the compressor. I think it is easy to see where the missing pneumatics and servo-motor should be.

Happy building

Becca

[unimog123]

Interesting solution!

[Becs]

Hello everyone! I'm back from a brief visit on the dark side.

Holy moly! Time flies darn quickly sometimes. I can't believe it's been almost a year since I last gave you an update.

If my memory haven't failed me, this monstrosity was completed in March last year and have since then been collecting dust on my desk.

I've been busy doing nothing at all since then. Not alot have been done in the way of MOC:ing, but some technic sets have been built now and then.

This creation has been constantly on my mind though, it's been to much of a bother to get it photographed.

Today I finally got my bum out of the seat and cleared my room enough to expose the truck. (My nose itches after brushing of almost 10 months of dust.)

I got my desk rigged for a photoshoot. But first I want to ask you, any special request for detail shots?

And before you ask, I will try to make a video, but due to space constraint there will be no driving around, hope that won't disappoint you.

As a consolation, (hope I don't bite of more than I can chew here) is there anyone interested in photo instructions of this beast?

No matter what, this behemoth will be disassembled after the photoshoot. The pieces will be counted, so I might as well give it a try.

Hopefully pictures will be up tomorrow.

Happy building!

Becca

[Milan]

Looking forward! :)

[rollermonkey]

As huge a beast as this is, I can't believe that a pair of L-motors moves it! Which are the drive axle(s)? How many wheels steer? What else is motorized? Is none of that massive length articulated?

Need more details!

Edited January 21, 2015 by rollermonkey

[Dafgek81]

Very nice MOC, only thing I don't like, it's a Scania.

[gevans12]

That is huge! I wouldnt be surprised if it doesn't give the upcoming MB Arocs a run for its money in the size stakes...

[Becs]

Damn weather, nearly hurt my back shovelling snow today. Almost makes me wish I lived in Glasgow.

@rollermonkey: The two L-motors drives it around quite easily across flat ground with reasonable speed. The whole thing weighs about 9 kg and about I'm guessing about 4 kg of that is located above the first axle. Not as much weight is over the rear axles is making them spin rather than push the truck over obstacles thicker than 1 cm. The other functions will be shown later

@Dafgek81: What's wrong with Scania? I'm a Swede, it's either Scania or Volvo, and I couldn't find as good blueprints for Volvo trucks as for Scanias.

Anyway, got some pictures taken:

The first two axles are steered by one M-motor with linkages just like the real truck. Axle five is self-steered but can be force-steered with pneumatics, I also built a pneumatic lock to keep it straight. Both pneumatic functions are controlled by Servo-motors.

Here is the interior. As you can see, it is build in double layers, even the roof, making the cab alone weigh 2 kg.

The steering wheel, here seen through the sunroof, is connected to the steering, as it should be

Here you can see the front walking table at its extreme positions. They are driven by one M-motor.

On the second picture you can see the prop shaft that is delivering power to axle three and four from two L-motors under the cab. Total gear reduction is 1:8,75.

And here is the rear walking tables, also driven by a M-motor.

The rear section is actually a trailer, but its built together with the truck making it locked from side to side movement. It is hinged though at the level of the hitch seen in red. On the real truck the whole trailer can be lifted by hydraulic rams under the hitch, I tried but Lego flexes too much and pneumatics are too weak to lift it.

The last remote functions can be seen here. Support legs for loading and the loading ramps, both driven by M-motors.

Looking at the truck from the rear you can see the tail lights of the truck shining, lights on trailer is working too.

The big grey box behind the cab is the automatic compressor.

The cab can be tilted manually using a pneumatic hand pump and valve located under the second axle mudguards. Here you see the Servo-motor and valves controlling the last axle steering. Created a small problem though, the distance to the axle makes it use up too much air for the compressor to keep up the pressure. Patience is needed when doing driving around waiting for the axle to steer.

Here is the first axle suspension. Air suspension reinforced with a spring to keep it from sagging. The cab is to heavy to lift with the compressor.

The second axle suspension. Almost the same as first axle, but different chassis width and prop shaft required a small modification. Here you see the pump for cab tilt too.

Third (and fourth) axle suspension. Air suspension here as well.

And finally the fifth axle. Air suspension all around You can also see the pneumatic hoses for the steering.

I just realized that the steering mechanism for the front axles are on the other side of the truck I will take some more pictures of that when I disassemble it.

That's all folks. Hope I didn't miss anything else, otherwise that too will be reported after disassembly.

All pictures from this photo shoot can be found in my Brickshelf folder once moderated.

Thinking about the video, not much to show really with it sitting static on the table. Are you interested in it anyway?

Happy Building

Becca

[LeocornoProductions]

Wow that's bloody huge, how can you make a moc so big that makes the 42009 look so small?!?! Great functions btw. That probably wouldn't be able to move in my bedroom.

[Askan]

It is really beautiful! And really a dunderbygge :)

Of course we want a video!!

[Epic Technic]

Now that is what I call impressive sir!

I wonder how it compeers to Lucio Switch's Tractor Truck.

[Mordep]

I build a 42009 recently and think that it is huge, but now seen those pictures

Maybe I failed to read but how much parts are in this??

[Lucio Switch]

Very Cool!!

I'm interested on the video, there are a lot of things to show, but not static if it's possible, drive it a little bit.

I will see the difference between 2L motors and 4XL motors.

Now that is what I call impressive sir!

I wonder how it compeers to Lucio Switch's Tractor Truck.

My would be shorter and faster (probably) ... I'm used to hear this sentence ...

[Becs]

I'm happy you like it

@LeocornoProductions: A large collection of parts allows for big projects. It can't move around in my bedroom either

@Mordep: I have no count on the pieces, that will come later when I disassemble it. Wouldn't surprise me if the count would be close to 10k

@Lucio Switch: Space might be a problem for driving, will try to find somewhere with good camera view to show it moving in a straight line just to show the speed, turning is impossible here

Comparing our trucks I see that yours is more detailed and built for performance, whereas mine is more built for mechanical accuracy.

I don't know what goal you had for yours when building, my goal was to build the functions to be as near the real thing as possible.

This had the cost of performance but that's acceptable for me. It's just my style of building, accuracy is high on the list for the perfectionist in me

Doesn't stop me from admiring people making things with other priorities, like yours.

Happy Building

Becca

[Lucio Switch]

@Lucio Switch: Space might be a problem for driving, will try to find somewhere with good camera view to show it moving in a straight line just to show the speed, turning is impossible here

Actually I had not thought about this problem , I understand what you say, I had the same problem with the tow truck. You need to go outdoor.

Comparing our trucks I see that yours is more detailed and built for performance, whereas mine is more built for mechanical accuracy.

I don't know what goal you had for yours when building, my goal was to build the functions to be as near the real thing as possible.

This had the cost of performance but that's acceptable for me. It's just my style of building, accuracy is high on the list for the perfectionist in me

My not wanting to be a critical, you are right about the fact that I focused more on the performance than about the mechanic accuracy (well, practically the drive transmission doesn't exist ).The mere fact that a heavy beast like yours can move it's already acceptable.

I don't think that there is too much difference about the details (I like a lot the seats and other things).

Doesn't stop me from admiring people making things with other priorities, like yours.

I agree with you! That's why I urge you to do a video, and not only for the speed performance. Like I said before, there are a lot of thing to show, like how the suspension works or the pneumatic sytem of the last axle.