četrtek, 24. marec 2016

Finished Oshkosh 10x10 PLS

After over a year of tweaking the digital version and gathering all the needed the parts the time has come...

First a short list of functions:
6L motors for driving - 3x for left and 3x for right driveline
3M motors - 1x for the gearbox and 2x for autopumps
2 Independent dual gear transmissions - Each for one drive side
2 Steering Servo motors - 1x for front 4 wheels and 1x for rear 4 wheels
10x10x8 Wheel drive with portal hubs - All wheels are driven and the 1st , 2nd, 4th and 5th axles steer
3 steering modes - Normal opposite wheel steering , Front only wheel steering and Crab steering
Very long travel torque sensitive double wishbone portal independent suspension on all 10 wheels - Total suspension travel is over 5 studs on all wheels
Double segment working hook arm with a total of 8 pneumatic cylinders - Is able to hook up and load a 0,4 kg heavy pallete
Two newly designed autopumps to power the arm - Each powered by a single M motor
Two X24 piston engines - Each connected to its own driveline side
Detailed interrior with 3 seats and steering wheel - over 20 studs wide this is one my largest cabins ever built

I got the idea for the model while playing with new suspension systems. I managed to build a very compact and robust long travel independent suspension. This suspension also allowed me to build H driveline in which left and right wheel drive are seperated and in my case can be independently driven. This kind of setup has many advanatges, mainly removing the need for differentials when offroading, allowing small speed differences between sides when cornering and improved maneuverability due to independent drive (the truck can even skid, but its not recommended on grippy services).
After searching online a bit I decided to try to make a 10x10 model of a real truck, the Oshkosh 10x10 PLS:

 This was my original reference


Because I wanted this truck to have some speed I decided to use L motors instead of the usual XL motors. But because this machine is also meant for offroading I incorporated a double speed gearbox for each before mentioned drive side. Because I wanted to have more than just a rolling chassis I incorporated a functioning arm hook which can remotely hook up and load the massive palletes. I had lots of room to spare above the front wheels so I filled the space with two X 24 piston engines. For the final touches the cabin was detailed with three seats and opening doors, and the engine was finished up with a massive exhaust and cooling systems.

The finished model is over 85cm long and weighs 5 kilograms

Notice the 8 wheel steering. The front ladders/steps are flexible

Thanks to the high travel of the suspension there is plenty of ground clearance

 The under shot showing the two independet left and right wheel drives

 Another view of the rear steering and the loading arm

 Here you can see the two dual speed gearboxes. 
No broken gears, but switching gears under high load may damage the clutches
 
 Outdoor photo showing off the truck giving the Coyote a piggyback ride

Front view of the truck offroading

Here you can see how the suspension adjusts to the terrain

 Even when unloaded the suspension still does its job

I also put a lot of time and effort in the following video showing off the finished model in all its glory both indoor and getting dirty outdoor:



As usual with my models I am also relasing the digital version which is available in my LDD package
 The LDD file for the final version can be downloaded along with my LDD package

I would here bye also like to thank everyone who helped me realising this model with your support and donations. A BIG THANKS TO YOU:)

 

sobota, 19. marec 2016

Oshkosh 10x10 PLS video coming soon....

I am now in the process of video shooting this massive model.

Got myself some fancy LED lights and greenscreen fabrics, they work awesome, here's a small preview:

Expect the finished video in a few days :)

četrtek, 17. marec 2016

Double torque tube live axle idea

 I got this idea yesterday and decided to build it.

Its an improvmement of a classical torque tube suspension, but now it uses 2 torque tubes to form two half axles which are connected to each other via a turntable:


To keep the half-axles from bending away there's a lower linkage made out of 5L suspension arms and some beams:




So what's the difference btween this and classical single torque tube?

Lets start with advantages:
- No need for links or panhrads to keep the axle in place
- Now each axle can have an independent drive, therebye elimenating torque flex
- Or you can use one ball joint for drive an dother for steering
- Can carry much more torque

And there are also some disadvantages:
- Less flexible, maximum angle this setup can bend to is some 30 degrees
- Steering is a bit more complicated, since the axles pivot in the center, you need some ball joints and links
- Takes more space

But you can even expand the concept to use three torque tubes.
Now the side ones can carry power while the center one supports the steering system:

I plan to try to use this new idea in future models, since it allows me to make a vehicle with independent left - right wheel drive with zero suspesnsion torque flex.

petek, 11. marec 2016

Livestream reminder

This is just a friendly reminder about tomorrow's livestream.


Also I took some time and imporovised and made my own csutom shelves s I have room to place all the sorting trays:

 Top shelf is where I keep most of my beams, axles and pins:

Lower shelf holds panels gears, connectors and suspension elements:

And the low box on wheels is filled with yet unsorted parts and bigger stuff:
 

To keep the shelf from accidentaly toppling over I used some old beams to wedge it agaisnt the wall:

It may not be too pretty, but it works :)

See you guys on my outube channel tomorrow between 10:00 - 14:00 and 16:00 - 20:00 (GMT+1)

četrtek, 10. marec 2016

Lego double beam suspension



After watching some youtube videos I noticed some trucks had some weird suspension on them...
It looked something like this:



So naturally I started investigating and found that this is a type of setup called a twin beam suspension.

So I tried to replicate one in Lego. To explain the concept behind this hybrid, here's a series of stages leading from live axle suspension to the double beam setup:

In order:
Yellow setup is a live axle
Red setup represent the change from dependent suspesnion to independent suspension
By extending the half axle lengths (blue) we get a lower change in wheel angle relative to the drive surface (camber)
And finally by extending the swing arms PASS the center point we get a double beam suspension


And here's a version with drive and steering:


So what are the advantages compared to the live axle?
- Its independent, which as name suggest aloows the wheel to work independent from each other
- Lower unsprung weight
- Less moving parts - to keep a live axle in place you need several linkages. Here the axle pivots around one central point

And disadvantages?
- Complex design, the axles have to be made to travel pass each other without interfering.
- A need for a CV joint which needs to allow the axle to slide in and out
- Not as robust
- Hard to implement portal gears without making the wheels slide sideways excessively
- Camber changes are still present

I also made a video explanation of the principe. You can skip to 4:30 to see the final version in action:


 

So the final question. Is it useful? Fo me as far as the Lego version goes....no. The disadvantages outweigh any possible advantages. Also lately I have been working a lot on long travel double wishbone suspension which outperform any other previous suspension system in almost all categories.

The only usefulness in this design I see is realism, if you are building a replica of a truck that has such suspnesion.

Because I want to hear your opinion, here's the LDD link to the suspension, so you can try to make your version and improve upon my prototype:
Download prototype here

sobota, 05. marec 2016

Oskosh 10x10 livestream announcement

After gathering the parts and refining the design for over a year the time has come...

...for my first ever real life MOC building livestream!

The livestream will be active in a week's time, exact starting time will be at 10:00 GMT+1 and it is going to be split in two four hour streams with a two hour break between them.

More info in the video:


Of course I will also try to do my best to answer any possible questions when I will be able to.
See you in a week :)

torek, 01. marec 2016

Work In Progress Sherp 4x4

So I was skyping with a good firend of mine, Braker23 and he gave me an idea to build the famous russian vehicle sherp.

So you might be asking, whats a sherp?
Well if a picture is worth a  1000 words I guess a video is worth a million.

So as you can see the sherp is a skid-steering 4x4 all terrain amphibious vehicle. Wow, that was a mouth-full :)

So after playing a bit in Lego Digitial Designer I came up with a simple prototype built around the small boat hull and for the wheels I choose a combiantion of tumbler wheels and inverted track elements.

So after tweaking a bit, here's the real version FLOATING in water (insert a F*** Yeah comment in here)


 More detailed view of the now hopefully-soon-to-be-dry version here:






And here's the money shot of the model's belly showing the reinfrocments used to keep from full from sliding out and wheels from spreading apart:





Where do we go from here?

Well I have to fix the issues of 36 tooth gears slipping at high torque, I need 4 more tracks (anyone got a spare to borrow?) and I need to make it pretty... But not to pretty, since it cannot support too much weight on water, so it has to be pretty like a model. Handsome and light.

In other news I ordered all the parts needed to finish the Silverfox and make the oshkosh 10x10, so keep checking my blog and youtube for updates.