my first topic, my first moc ...
With this moc a had two goals building a tracked vehicle:
1. Make it as small as possible
2. Maximize playability with lots of power functions
To the first point: the distance between the tracks is only six studs and the whole vehicle fits into the shovel of a 42030
And now the power functions: it is using a 8878 rechargeable battery box, an SBrick and four M-motors. Two motors are used for driving and there is a subtractor inside (which means one motor runs the vehicle forward/backward, the second motor is turning it left/right). The third motor runs the container lifting device at the back and it also locks/unlocks the trailer coupling. As it is double worm geared it is very slow, but very strong. The last motor runs the lifting device at the front. As there was absolutely no space left for any more gearing, it works by using a rope and a set of pulleys.
Enough words, here some more pictures:
As you can see these are pictures made with the LDD and so it was easy to extract the power functions:
All just digital? Of course I know what you are waiting for. And here is the video showing this little thing in action:
If you like my creation and want to copy it you can find a LDD-File here:
There is also a background picture availably for your SBrick-profile (as you can see in the video). Maybe you have to adjust the resolution depending on your mobile device.
Some notes to the LDD-file if you want to copy this:
42003 on the roof are not placed exactly as this is an illegal lego connection. Watch the video for exact position.
Same for 32039 at the rear axle.
The lifting device at the front needs a rubber band to keep the rope tight. Otherwise the rope would fall of the pulleys.
For the lifting device I used a beam with ball cup which is not available in the LDD. I replaced it by 6M Half beams and a 2M cross axle.
The cable routing is quite tricky as the vehicle is so small. I used same cable fixer to make this easier. Ok, no Lego-parts. Shame on me. But you can get them in every do-it-yourself store for a little money.