Lego Raptor walking robot biped 2.5 - 2.8. I am working toward Raptor 3.0 by experimenting with a leg that flexes side to side and linkage to control the foot path so that it travels under the center of gravity with as little tipping as possible. The leg has to move forward without colliding with the other foot.
Lego Raptor 2.0:https://youtu.be/dZIsDstTSUE
Lego Raptor 1.0:https://youtu.be/Y-TmDSCBgX8
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https://www.youtube.com/watch?v=rZ1Kk8oHPAw
Unstoppable Lego Technic ATV 4x4 MOC. It's invertible. It goes through buckets of Lego bricks, downstairs and over logs. I really like the short wheelbase.
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https://www.youtube.com/watch?v=eKMcXt1z3cs
Lego 4 speed gearbox. Work in progress - Disclaimer: not good. Just something to consider. There are many different ways this could be put together.
Discontinued LEGO L-motor still a good price June 2021 https://amzn.to/3fVarC2
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https://www.youtube.com/watch?v=Wyh3trdV0l8
2 speed automatic Lego transmission this time with rubber bands instead of springs. It's still super smooth shifting. The rubber bands and wheel/string arm make it way easier to get it to work.
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https://www.youtube.com/watch?v=BDL1XozRxPQ
The Lego L-motor powers the pump that pushes the air prompting the projectile out of the pistol and it packs a punch.
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https://www.youtube.com/watch?v=UlDqlu-UmUo
2 speed automatic gearboxes with less friction. 3:1, 1:1 and mixed ratios so it's like a CVT. Two ways two build it. One of them is even smaller than the original from another video. Both are more efficient and have better framing than the original.
The original uses the other diff not used in these so that might be useful too https://youtu.be/fKXB2s7AdaM
Lego has discontinued the L-Motor
LEGO L-Motor Still a good price June 2021 https://amzn.to/3fVarC2
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https://www.youtube.com/watch?v=gM_7IkzWvtY