TBE's RTC Bipedal Walker Leg Design

This is a guide on how to make simple legs for a bipedal walker that will always return to a standing position, no finicking required!
I developed this mechanism while working on my bipedal walker that i uploaded to the forums, Theta. [forum.spiderlinggames.co.uk]

This guide will not exactly show you how to build the mechanism, just how it works and its relation to the human body as a source of inspiration. If there are suggestions on how to make this guide better and/or more comprehensive, i will edit the guide as necessary.

You can find my original, far less in-depth version of the guide here [forum.spiderlinggames.co.uk]

I developed this guide and mechanism myself, and if it bears any resemblance to another guide or mechanism someone else created, or that you created, the similarities are coincidental and not meant to infringe upon a preexisting idea or explanation.

Introduction

Terminology and Background

Firstly, i tried to imagine how a human would move its body, and how to translate that into Besiege. This required some knowledge of muscles and how they worked, but not a biology degree or anything. I used a corpse diagram of how muscles worked that i found in a human body book laying around as a point of reference. it was similar to this:

Leg Mechanism

Mechanism & Explanation

The muscle is connected to the bone by 2 ligaments and when it needs to move the bone, it contracts. I tried as best I could to emulate how a human ligament-muscle system of movement works using a simple hinge-piston-brace system.


The front of the piston is attached to the "bone" by a brace, so that when it contracts, it's pulling on the hinge, which is connecting it to a seperate part, and that causes the main "bone" to be lifted in whichever direction the HPB is. As you can see, there is a hinge-piston-brace (HPB) system at each joint. When not moving, they support the weight of the machine using their spring-like properties, and just stay still. I usually have two HPB's on each joint so they can better support the weight, and also so that if one breaks, you still get some movement. If you want to reduce weight, use only one per joint and increase the strength.


I have it mapped so that the legs move with the left and right arrow keys.
When pressing either [LeftArrowKey] or [RightArrowKey], the corresponding pistons will contract, like muscles and ligaments. In this leg's case, [RightArrowKey] causes forward motion and [LeftArrowKey] causes slight backward motion:
Pressing right:


Pressing Left:

Foot Mechanism

Foot "Mechanism"

My foot "mechanism" isnt exactly "mechanised". The foot just keeps balance better, thus taking the strain off of the balloons, or in the case of the aforementioned Theta, the Knight. The foot, unlike the leg, doesnt really have any sort of image or hard scientific reasoning to back it up, just a basic thought and some blocks. And really, thats all you need in besiege, lol.
My custom foot design is also based off of the performance of a real foot: provide balance for the body. The way it does this? The base of the foot is a ball joint, and on each corner of the ball joint, there is a small suspension block with its own ball joint connecting it to the calf. This makes it so that the ball joint can still move, but with heavy resistance and return-to-position functionality. This keeps the mech standing upright while allowing for slight terrain crossing capability, and ability to deal with rough landings. To further improve impact tolerance, mount the foot assembly to a suspension block instead of directly mounting it to a ballast or otherwise rigid block.
Range of movement:

Review

Review of Everything (basically a TL;DR)

I used a hinge-piston-brace system to replicate the function of human muscles so that the leg can walk and return to standing position. I also used the fan blocks to increase walking speed but that doesnt matter much.
I attached the HPB's to the joints of the legs to provide mobility in the most efficent way possible.
The feet are ball joints with suspension blocks on each corner that allow it to absorb angular impacts and to balance more easily.

SIDE NOTE:
oh my god typing this is making my wrists hurt so badly i need to buy an ergonimic keyboard or something uuuuuuuuuuuuuuuuuuugh
ALSO im typing this at 4:30 in the morning so i can hardly keep track of what im doing
i wrote the same paragraph TWICE before realising it and i probably left spelling and grammar issues all over the place so uuuuuuuuuuuuuuuuuuugh x2
END OF SIDE NOTE

I hope this helps any aspiring mech makers! I came up with these on my own, which means that any of you can come up with better, so keep on building and keep letting dumb ideas come to full fruition!

also if you want me to put Theta on the workshop instead of leaving it only on the forums, then i'll do that when i've slept at least 10 hours and have had my 2nd morning pepsi and 4th bowl of cereal

[TerabyteAIX]

Nice, before this I just made quadruped designs using the spinning bar technique

[Lemon]

F U C K H A N D S

[TBE]

thanks
i will say tho, the guide is kinda old and the legs aren't that good compared to proffessoinal walker designs, but it is a good place to start. thanks for using my design!

[misu]

very helpful

[Jessica]

ey