Progress

Model of landscape with reinforcement layer

 Landscape with porous structure

Section view

Delta robot upgrade

So this is the last (final) version of robot. It still needs some final adjustments and of course a proper base. I managed to get nice ball joints so the movement is a bit smoother now.

Moving robot

Building phases

Year 0: plain landscape

Year 1: landscape with reinforcement layer

year 2:  additional layer of mesh above areas which are supposed to be inhabited

Year 3-5: as the wind blows more and more sand accumulates on one side of dune. This new pile of sand will be stabilized too, which will make the shield around inhabitable area more porous and thus better to create shadow and microclimate.

Year 5-10: loose sand inside of dunes will be either dug out  or blown out by wind. Inside spaces will host human activities as well as gardens. Plants will be able to grow underneath less dense mesh which will provide shadow and protection against harsh winds. 

 Section through multi layered structure

Interior of stabilized dune

Reinforcement layer

In order to make the surface of dunes after excavation more stable I decided to add a layer of structure which will respond to pressure and tension forces. Dark gray areas are the areas where according to previous dune movement  could sand accumulate and so bring more load. 

Major stress lines on shell surface of dunes, evaluated by millipede 

Urban layout

Scheme of urban layout based on topology. The arrangement of different  functions is represented diagrammatically.

Different spatial situations defining different typologies

Sand dunes movement

I took specific sample of landscape which I found near the city of Timbuktu. This city suffers as much as other sub-saharan city from desertification. Wind is moving masses of sand from the north east toward the city. I found satellite images showing this area between years 2003 and 2013. Based on this images I analyzed the movement of sand in my chosen area.

Overlaid map is showing the movement of dunes within 10 years. Arrows are dominant wind courses. White areas represent previous dune positions, yellow lines show direction of movement.

Section through the overlaid landscape

Site

The picture below shows villages in sub Sahara Africa. Each village is surrounded by mound of sand dunes. Moving masses of sand endanger houses and  keep village from growth. Local people are fighting desertification by building rectangular grids on the surface of dunes. This grids are made of tree branches or any other biological material, which prevents the sand grains from blow of the surface of dune. One of the main problems is that the geographical location of the Sahara desert does not enable simple growth of vegetation on its dry, parched surface. Also poor locals often collect this wood to obtain firewood for use in kitchens. 

I see here the potential for use of my delta robot which could in first phrase supply the anti desertification grid and in second phase create new inhabitable spaces inside of solidified dunes.

Active dunes covered with anti-desertification grid

Robot moving through the landscape

I wanted to create robot which would be as much autonomous as possible so only little or none human assistance were needed. Shift of the whole construction from one workplace to another seemed like problem because robot has just three legs. I tried to solve this problem by adjusting the leg structure and changing the behavior of middle platform( carrying the lenses) so that in some situations it would work as a supporting fourth leg.

Scheme of robot moving from one triangular workplace to another

 patterns of movement

Inverse delta robot

After some time spent at designing of the final robot I decided to radically flip the whole construction. There were multiple reasons to do that: I wanted to make the machine suitable for extreme environment, light and easy to move from one place t another. By flipping the construction I got rid of the additional three legs. Except of that I decided to use fresnel lens for  solidifying the sand, so I needed the construction to cast minimum shadow.

Digital model of delta robot with its maximal work space

Different types of optic lens- fresnel, hemi-spherical and spherical.

Model of robot as it would look like in scale 1:1

 Visualization of robot at work

Prototype variations

Material tests

After adding a glue extruder I was able to do some  material tests

 I have tried both ways of printing and I used different types and concentrations of glue. The models below where done by overlaying layers of glue and sand.  After the glue dried I removed remaining sand. The whole structure is very porous but also stiff.