Structural engineering with cardboard

Moving into a new flat I have ended up with a lot of cardboard and have actually struggled to get it to all be taken away. I then saw this Kickstarter on hacker news which introduced me to the idea that I could perhaps use the cardboard I had been throwing away the whole time. I have been toying with some ideas for building myself a robot, or at least a robot arm but they seem to be just ludicrously expensive and still not able to lift much weight.



One of the problems with the advancement of robotics is that although processing power has come down in price at a rate that no other product ever has, the cost of actuators (The motion inducing components like motors) has remained largely the same. I want to explore an idea I have for using cheaper motors in a robotic arm in another post though.

The problem I want to look at here is the possibility of being able to use cardboard, a material which can almost be considered to have a negative price, as the structure to the robot. I love the ideas of a robot which can produce its own tools from the materials around it. Generally, when I think of this I am thinking of the robot carrying out the carpentry to build itself new limbs or replace damage limbs it has.

The idea spawned from the kickstarted campaign was that it might be possible to use the more ample material of waste cardboard to produce the body of the bot.

Perhaps with restructuring, it might be the material I needed to be able to cheaply produce things that I wanted.

I had been considering getting a 3d printer although the reason behind that was mainly to be able to produce custom gear systems for the robotic design it would also have been useful to use for the body of the robot. 


What if I could make use of all the cardboard I had been throwing away.


In my curious googling around the topic, I found this paper which describes the fundamental strength of the cardboard but I wondered what would happen if I experimented with different sized prisms of the material and perhaps even looked into the idea of making cardboard ply with wood glue.

People have made furniture out of cardboard that seems to be strong enough for its purpose.

What I was imagining was taking a prism of cardboard, varying the size of the base triangle, the length of the prism and the number of wraps of cardboard per prism.

I imagine there would be something akin to the following setup to measure what I believe is called the shear strength of the cardboard structure. Here we secure the prism on one side and add weight to the other side measuring the total weight we can add before the beam buckles.


We could then measure the compressive strength using something akin to the following setup although I'm not sure how you would get reliable readings given the prism is likely to fall over with the weight atop. Any support provided to stop it falling over will affect the measurement of the total weight before the beam collapses.


I realise that this post would be much more useful had I actually run the experiment and had numbers to hand. I would counter that with that this blog exists first and foremost for me to explore my ideas prior to or as a replacement for building the projects.

Perhaps I should stick to putting the cardboard in the recycling, rather than leaving a pile in the kitchen for my girlfriend to fall over.

A non-robot use for the cardboard.



I had been considering getting something to vertically grow strawberries in up the window. The plastic solutions on amazon seem to be quite expensive and so I wonder if it would be possible to design a solution using waste cardboard which I could then spray paint to make a more appealing colour. If I could create column I could then either grow the strawberries in plastic bags or old water bottles.

That way I could reuse a lot of the waste and have a custom system that was to spec.


Comments

Post a Comment

Popular posts from this blog

THREE.js: minecraft in a weekend

Image
I have been enjoying exploring the ideas behind procedural worlds and in a previous post even showed a simple voxel renderer based in THREE.js which would load chunks when the camera got close enough to the edge. That was based on the great tutorial here which explains how to create a voxel-based mesh in THREE.js such that it doesn’t use all of the machine’s resources for the smallest of worlds. I found that to be an invaluable source of information and continually referenced back to that throughout the weekend. Looking back at my git logs for this project to be able to type this up, I have no intention of this post being a tutorial in itself, my progress was as follows: Walking around rather than observer view Sideways collision detection - not walking through the map Changing to a system where there was a sensible grass - sand - water height system Adding trees Another optimisation for terrain generation in addition to the afor...
Read more

Picking apart Perlin noise from first Principles

Image
Although there are a lot of tutorials explaining the what and even the how of Perlin noise and the general class of algorithms; gradient noise, I have found none explaining the why behind the algorithm. Why does this algorithm work? In this post I aim to build up perlin noise from first principles, explaining why we add each element to the algorithm as we do. We will start by trying to make a surface, perhaps for a computer game world map. We are aiming for something that looks like a mountainous region. We don’t want to hand craft this landscape as we want it to go on forever, how can we procedurally generate this world? Given we want the surface to be random, we could start with that. However as you can see that doesn’t lead to the most pleasing of surfaces, in fact it wouldn’t be traversable in the game. Our problem is that there is no smoothness from one place to another. The lowest of points could be adjacent to the highest of points. What we want is for it to take som...
Read more

The invincible 20 year olds

Image
It is often said that people age 20 think of themselves as if they’re invincible. It’s an attribute most commonly given to young men in general.  The idea of immortality is one which comes up in mythology a lot and sometimes it comes up within scientific circles. Bacon spent his life in search of finding ways to become immortal until, in perhaps an ironic way, his search killed him. When immortality is spoken about the concept of ageing is often also brought up, Tithonus comes to mind. Solving the problem of ageing through does not lead to immortality, although it may seem to be that way. Each year you live your chance of dying that year increases. This is how the ageing process manifests itself in this side of the numbers, growing from a low of 0.01% age 5 up to almost 40% age 100. What if instead, this didn’t rise. What if every year you had the same chance of dying as wh...
Read more