Not sure if anyone here is old enough to remember an obscure model kit from 1987 by Bandai called Revolt Bearmobill (Bearmobill is not a typo, btw). It is a walker like AT-AT from Star Wars except that it does not quite actually walk with those legs.
Revolt Bearmobill uses a moving motor and gravity to move the rear legs to the front to move forward. Notwithstanding its impractical locomotion, it has a very futuristic vibe to it. Anyways, YouTube channel JK Brickworks saw the said toy and set out to create a LEGO version of it. The result is, not surprisingly, super cool.
JK Bricks’ Flip Walker, as he calls it, looks like a machine that flipped right out of 2015’s Tomorrowland. While it may not be able to steer, this LEGO Flip Walker is capable of going up and down low steps.
Just like the 1987 toy, JK Brickworks’ LEGO Flip Walker has a motorized cabin that runs under a body which is essentially a loop. Near each end of the loop are a pair of legs that are set downwards by the virtue of gravity.
When the weighted cabin (which weights a pretty hefty 380g or 13.4 oz.) reaches the front, the weight forces the rear to lift and as it reach a pivoting point, the cabin continues forth, thus completing the flip.
In this process, the rear legs are lifted and when the flip is complete, it becomes the front legs and the cycle continues. It is a strangely mesmerizing process. You can check out the design breakdown in the video below.
Images: YouTube (JK Brickworks).