Hanging around

Guerilla tensegrities have an unpredictable lifespan. Not necessarily by decomposition, that happened only twice as far as I can say, but rather due to their accessibility. If it's easy for me to install them, it's easy for anyone to take them, whether for their own enjoyment or as part of their paid jobs.

I released 13 objects into the wild so far, with only two or three still in place. I still wonder if my motivation reflects more narcissism or exercises in letting go. However, I cannot regret the experiences I made, the bits of adrenaline rush while doing it, and about how to increase the positioning to appeal at least to me when I cruise through the neighbourhood to check whether they're still in place.

The first object I released took the most effort and excitement, and it lasted for nearly a year. A three strut minimal tensegrity made of pencils, attached to a power wire with an elaborate mounting mechanism. It survived many periods of wild weather, and I found it on the ground after the attachment broke, still intact.

Yet I wonder if it was ever noticed, being tiny and in a place the usual gaze would wonder about to find something unexpected. Two objects of similar size in plain eyesight were gone quite fast, and lately I went to much bigger sculptures for outdoor installations - I ran out of space, and I hoped to increase their visibility.

The first sculpture put up in a place for its splendid visibility didn't even last 24 hours, installed in a stealthy night action it was gone before I could take any photo during daylight. Another one, which I placed in the trunk of cut-off tree, survived some flooding from the creek next to it, and I adjusted it several times for maximum viewing pleasure, is gone now as well.

My attempts to attached some medium sized octahedra on top of wooden poles might have gone with the wind - I found one of it next to the pole after a stormy day, yet I'm sure now that the way of attaching them is simply not viable.

One of the objects that is still happily hanging around, provided me a flood of synchronicities. I met someone living just about 50 metres away from where I hung it out, having one of the most amazing sunday afternoons, a day after it got into place.

Initially, it hung much closer to the branch it's suspended from than I intended. I wanted to give it visibility and freedom of movement, and instead pulled it very tightly to the branch. I still have no idea how it lowered itself down, the elements might have helped me in giving it a more prominent position. One day, instead of being snuggly close to the branch, it had at least the little bit of clearance to rotate in the wind, became more visible, and is now affected by the slightest breeze.

It's now about seven weeks that it's hanging around, and I haven't got a name for it. Hold on, I just found one: Louise, please. As it's along one of my favorite bike paths, I will have ample opportunity to check on its longevity.

Louise, please (6 strut icosahedron)

Rainbow Buckyball

After a quite disappointing season on the Rose Street Artists Market, I had a break to reconsider the direction I want to take my tensegrity work to. I want to increase the size of sculptures, but with only limited space available, and no marketing opportunity for bigger things it's not something very feasible at the moment.

So I came up with the idea to make my third buckyball, a truncated icosahedron requiring 90 struts, this time using 6 colours. With the two colours versions I already found out how to structure different colours, and I had at least a plan. There's 12 pentagons in the buckyball shape (which is basically the same layout as a soccer ball), and 20 hexagons. Using six colours means each hexagon can contain all colours.

I thought if I start out with the pentagons, each build in a single colour, it should work out in this way. It still turned out as some tricky puzzle, and the actual build took me as long as the preparation of all the elements.

After building the twelve pentagons, 60 struts were gone, and 5 five struts of each color left. Each hexagon in this tensegrity consists of the struts from a adjacent pentagon, and three that connect to another hexagon. I had to figure out a build algorithm that allowed the hexagons contain all colours, which took me only two attempts.

There are two pentagons of each colour, and as expected, they appear on opposite poles of the finished structure. To my surprise, the remaining five struts of the same colour form an equator, only this configuration warrants that each hexagon contains all colours. This symmetric distribution of colour doesn't continue with the hexagons, all of them seem to have a different variation in the way the colours are arranged.

While I expected to have at least two hexagons in 'rainbow configuration' (yellow, orange, red, purple, blue, green), it might not be possible to achieve this, but I really can't be bothered to reassemble this sphere, or to transform this into a mapping problem. The weight means it's best to suspend this sphere, which measures roughly 45 cm from pole to pole with 20cm struts.

Rainbow buckyball (90 struts)

Caught in the act

I have too many larger sculptures that want to be seen. As I haven't found a gallery, and carrying more than one of them around doesn't work too well, I outsourced some of them. Three of them vanished so far, two of them disintegrated, and four are currently on display in the neighbourhood.

Tet-a-tet

Installing my sculptures in the middle of the night has some trade-offs. One that I really liked vanished in less than 24 hours, without me having any chance to see it hanging in daylight. Another one hangs much closer to the branch its dangling from than I wanted, I couldn't see my progress in lifting it up and so it ended up too high for my liking.

My last attempt to install something on top of one of the wooden posts failed as well, not too mention the bruises I got in the process. As I fail to notice any illegal thing in placing tensegrities in the wild, I simply decided to use a break in rain to do my work.

I wanted to use a tetrahedron made of string within a tensegrity tetrahedron as mount point, which meant 'squaring a triangle. My rough measurements worked out okay, a tighter fit is still possible.

I admit, I used anti-stealth mode. As the winter came back with a cold spell, I wore my space jacket. Lazy as I can be, I rode with my unicycle, carrying a relatively large sculpture in front of me.

At my target, I saw a young woman contemplating on the bench next to the post. I smiled over to her, leaned my unicycle to the post to easily reach the top, and to my pleasure, my idea how to slip the string tetra above the post worked well.

Tet-a-tet a bit closer

I didn't wait for the sun to come back for better shots, did my best to adjust the sculpture as balanced as I could, and happily cycled back. I passed a group of people that had seen me before, one of them asked me: Where's your little thing? I just shrugged my shoulders, with a big smile, and another one commented: "Very Brunswick". Indeed.

I still have to have a second look in sunlight. The visibility seems fine, but the tetrahedral shape has least appeal. A square within a tensegrity square can use the same mounting technique, and might look much more stunning. I still need to make a choice about the strut length, I think 30 cm could be too small for a dramatic effect.

The great outdoors

With the formats and materials I used so far, my sculptures suit indoors much better than outdoors. Yet bamboo and nylon can withstand outdoor conditions, it just needs some more considerations.

I was a bit surprised when I brought a larger structure to the market on a rainy day. It lost considerable amount of tension, and also its delicate balance. Some similar happened when I spray painted a larger structure and left it outdoors for drying, on the next day it had gone into a dangerously floppy state.

My last experiment involved a 4-strut tensegrity, which basically could be balanced upside-down, with one strut fixed into the ground, and three struts floating in tension. The model reaches about 160 cm up, which gives me a bit of leeway for the tension. The first build felt okay, could be handled without disintegrating and lots of movement throughout.

I installed just before a rain storm broke out, with some significant winds. The next day, I found it still in place, yet the top three struts had folded down. The rain must have allowed the strings to stretch more than a healthy amount, although no connection become undone, the overall tension didn't suffice anymore.

With the strings still wet, I simply tuned the model by looping the strings in their grooves, taking care that the overall symmetry wasn't gone. Only 12 strings are needed to keep the 4 struts together, but I wished I had more than two hands while I tried to give it more sturdiness.

I sealed the top of the struts with a glue gun once I was happy with the overall tension, and gave it another go.

New life (in a mist of breath in a cold night)

The Melbourne weather brought a bit of sunshine the next morning, so I could finally hope for a shot in daylight. After straightening the structure in its base a bit, I was quite happy with the result. The visibility isn't too great, but I guess the sun will bleach the struts which currently blend into the background a bit.

I can only hope that the council won't rip it out too soon, it's along my favorite unicycling route so I have a fair chance to keep an eye on it for some longer. It's very accessible, and I rather have it taken by a flooding Merri Creek than over-eager council worker or some destructive neighbours. Time will tell.

New life (in an old Willow tree)

Filling the void

I started experimenting with combining tensegrity structures from the very start of my explorations. Most of the results used models of similar dimension and base geometry and some sort of quick and dirty approach. It took me a while, and some larger sculptures to deviate from this idea, and the initial set of combined structures had a clear defined orientation in space.

The idea of core and shell allowed me to create more complex structures which still can be placed in a variety of orientations. It also taught me experimentally that Buckminster Fuller's idea about the tetrahedron as smallest 'building block' of the universe can be demonstrated with tensegrity models.

Although I haven't attempted yet to exactly model the volumetric relations between the Platonic Solids as described in Synergetics, the 'compatibility' of all these highly symmetric structure becomes very apparent. Tetrahedra fits easily into 6-strut icosahedra, 12 strut cubes and octahedra, and 30 strut dodecahedra. Most likely also in 30 strut icosahedra (the most common tensegrity sphere), I just haven't bothered yet to build one.

Cubic merkaba

Octa Octa

Icosa Icosa

Inner strength

I got asked to build a tensegrity model that shows excitability on the outside, and has some core adding resistance against heavy loads. That's the inspiration for the Inner Strength models, both of which have already arrived in Queensland, with one unfortunately broken in transport. 

Inner Strength - Purple Heart

Inner Strength Purple Heart served as concept study for this idea. I used an already build up octahedron and experimented with ways to install an icosahedron in its centre. The most difficult part was to figure out the length for the tendons leading to the centre, they needed enough tension to withstand forces. Probably too much, one of the purple struts broke while the model was squashed by something heavy during transport.

Inner Strength Hard Core

I used the experiences from the first build to play with the variables a bit - a heavy, solid core held by low diameter struts for the octahedral shell. The weight of the core adds to overall tension on the outer shell in seemingly stabilising way, with still an amazing amount of varying movement throughout the structure.

Cube in octa

I already discovered that I didn't need struts in the centre, tetrahedron, octahedron and cube can be constructed by tendons joined at the corners. The Cube in octa is suspended from the center of the triangular faces of the octahedron, creating redundant network paths. The nylon tendons highlight that the cube was made without struts, and embed a familiar shape in a less conventional surrounding.

Copped Hypercube

Copped Hypercube was my first attempt to suspend the frame of a Platonic Solid in a small scale model. The struts of this model were recycled from a models that lost most of its tension, after being very floppy to begin with. The current emanation is extremely springy, and it seems like the cube adds resistance against total collapse, while some its edges slack off.

It's fun to build a framework entirely from string, so that it entirely depends on tension to hold its shape. I will have to upscale to find out more about the change in behaviour depending on the relation of inner and outer structure. The large scale model on display at the moment has a tiny tetrahedron in relation to its out shell, which still seems to contribute to its overall stability and movement.

Youtube

I decided to open a new account for all the tensegrity related videos I shot. As the user TouchThisTensegrity you can find slideshows, howtos and exploration of single objects on youtube. By and by, I will replace the videos in blogposts here with their new location.

It's also a good starting point to collect playlists of other tensegrity explorations. Hope you'll enjoy the new channel.

Changed market dates

I can't come to the market on June 24th. I will figure out next sunday which alternative date I pick, and what to do in the next market season. However, I found a new way to relatively safely send models via mail, so your last chance to obtain one of my wonderfully weird works hasn't come yet.

Market

As you can see in the latest entries, I have been quite busy lately. Many of the new models will be on display tomorrow, Sunday April 29th, on the Rose Street Artist's Market in Fitzroy. If you're in Melbourne, and have never been there, come and enjoy a variety of goods you can't find easily anywhere else. See you there.

Wrap up

I hope my thirst for novelty got quenched for a while - I still feel the itching to build something fantastic, yet I'm more than happy that I mastered some structures which posed lots of challenges. What started off with revisiting the x-module, and having some tetrahedral galore, ended with a four tensul (3 strut prism)  multi-coloured tetra with non-elastic string which balances in 20 constellation (four corners, four faces, six edges in two constellations).

Vier gewinnt (12 struts, outlining an tetrahedron)

Although I like the visual effect by using different colours, when I tried to make a digital 3d model out of the structure, the optical continuity of same coloured struts overwhelmed the software, and led to very blurry results. However, when shot against a suitable background the colours create many interesting perspectives, and even without being collapsible, the structure is very playable.

Vier gewinnt

I drafted the model with elastic string, using nylon for the 'base' of each tensul. It was tricky to balance, and untuned itself easily. Once I replaced all tendons, the model had movement as well as balance. I dread scaling the concept up, as the build was quite challenging with plenty of hick-ups on the way.

Clover (6 strut tetrahedron)

Clover isn't really a new structure for me - it's tetrahedron where the struts meet in close proximity at its center, instead creating more clearance and 'central space'. However, in this configuration more symmetry than usual can be seen, especially with the use of different colours. Nylon provides plenty of sturdiness, and with my corner configuration it looked a bit like a 4-leaved clover.

More rip-offs

The success with rebuilding the tetrahedron based on Marcelo Pars' idea motivated me to do more as yet unexplored structures. There's still some challenges I want to take on, watch this space.

Caged rainbow (18 strut tensegrity cube)

The simplest of my new structures just adds 6 struts to a cube with changing chirality along its corners. Similar to a dice, where opposite sides add up to seven, colours oppose each other of each side. Snelson managed to build an x-module in a way that outlined a tetrahedron, I was surprised how well my guestimation for the different tendon lengths worked out.

Tetra ala Snelson

It might look better when slotted into a base, so that only one strut connects to the ground, similar to Earthlon, which shows the 'ascension skylon' out of Burkhardt's collection of structures, and turns it around.

Earthlon

I drafted Earthlon with elastic strings. but it gained much stability with less elastic tendons. It has only little movement, nevertheless looks quite surprising.

Polarised canary

Polarised canary took quite some time to get together, and probably the tendons holding the upright strut could be a bit shorter. The same concept should work with three struts on either end, and looks a bit like a beam capable of absorbing shock along its length.

Homage to Pars

When I came across the website of Marcelo Pars, a Dutch tensegrity artist, I knew that my explorations wouldn't find an end soon. The site looked a bit different at the time, but had already some fantastically inspiring pieces on display. I had the impression that he builds models on a larger scale than I do, and much more with 'redundant' struts that I explored so far.

Besides exploring basic geometry, he managed to give his objects a solidity in appearance (and potentially in mechanical behaviour) that eluded me. I totally enjoy the ethereal appearance of some of my own structures, and managed to resist the call for more solid struts.

Parsed Rastafarian (12 strut tetrahedron)

While I consider the tetrahedron (in some educated believe in Fuller that the tetrahedron comprises the smallest unit in universe) a very appealing shape, most people exposed to my work prefer the icosahedron when it comes to 6 strut structures.

Parsed Rastafarian (sitting on a tetrahedral face)

While playing with the Java tensegrity viewer by Bob Burkhardt, a pioneer of constructing tensegrity structures, I realised have easy it should be to build a 12 strut tetrahedron like Pars did. I had a small colourful tetrahedron lying around, and decided to transform it. 

Parsed Rastafarian

The tetrahedron 'proves' that one and one add up to four, and it hides 3 pairs of orthogonal edges in it. Three colours suffice to show this twisted pair of edges. While I love many visual aspects of the small version, it's tricky to balance it on all corners, and the relative large diameter in relation to the length of the struts brings the struts nearly into contact.

Homage to Marcelo Pars (12 strut tetrahedron)

The proximity of the struts could easily be changed by upsizing. The corners are held together in a single spot, I'm tempted to connect the corners to the center. Well, as the first emanation with 60 cm struts already has quite a large prestress, I might delay this idea until the next build. 

Homage to Marcelo Pars

The larger build unveiled the space in between the intricate weaving patterns in the center of the sculpture. I'm still hesitant to play it hard, I had some accidents during the build and it feels so taut that I fear to break some of the flimsy struts used.

Genesis revisited (4 strut x-modul)

My attempts to scale the classic 4 strut x-module up didn't succeed. The 30 cm strut version, very taut with only nylon string, can easily be held in balance by slotting into a relatively heavy base. I hope my lungs didn't take damage from drilling the fibreglass base...

Double plus good

Using two colours for the tendons allows to show the 'centre' and 'periphery' of the x-module. Using two colours for the four struts will enhance the polarity of the struts, could be fun be find out how a chain of x-modules behaves. I did this before, very early in my tensegrity exploration, certainly worth doing again.

Pented up

The small 30 strut dodecahedron I had lying around didn't really invite for playing, so I thought in combination with a basis its wobbly qualities come into good use.

Explorations

After building a relatively large number of tried and tested icosahedra and octahedra, which so far exceeded the demand by far, I went back to the fun of exploring other shapes and build methods. Floating Spell is an adapted pentagonal prism, with the top struts connecting across the center.

Floating Spell (20 struts)

Five Elements creates different views from each angle, with two of the twelve pentagonal corners appearing copper from the outside, and black from the inside. Each strut looks basically identical, nevertheless a variety of pattern appear throughout the structure.

Five Elements (30 strut tensegrity icosahedron)

12 Meridians belongs to the recycling projects among my latest explorations. After deploying the centrally joined corner tendons, I rebuild a dodecahedron with black and white struts, which failed to impress me in its first incarnation.

12 meridians (30 strut tensegrity dodecahedron)

Balanced Infinity is a 12 strut cube with centrally joined corner tendon, and elastic string for the tendons along the edges. The model feels very floppy, yet when handled gently balances on each of its eight corners. It can go through quite some interesting before losing balance.

Balanced Infinity (12 strut tensegrity cube)

Star Icosa stems from the ambitious idea to build a 30-strut icosahedron entirely with non-elastic string. So far, my attempts usually lacked the precision in tendon length for satisfying stability in 30 strut models. The star connected corners looks especially interesting under UV light.

Star Icosa (30 strut tensegrity icosahedron)

Redfaced Revisited is another recycling project. The original Redfaced had transparent elastic tendons, It has a cuboctahedral shape (Vector Equilibrium), and handles nicely.

Redfaced Revisited (24 strut cuboctahedron)

Polar Symmetry belongs to the experiments with scaling up. Although the nylon string has only little elasticity, the model can collapse on itself and bounce back.

Polar Symmetry (6 strut tensegrity icosahedron)

The next three objects a variations of the same structure, utilising central corner joints. Green Bridge shows the pure concept: 4 20cm struts rising near vertical, two 30cm struts crossing in the center along a horizontal plane. 

Green bridge

Fiercely occupied uses different colours for the different tendons, and has a Pokemon as inhabitant.

Fiercely occupied

Gargoyled Tetra is also inhabited by a Pokemon, and also outlines a tetrahedron with the four orange tendons in its center. The tetrahedral pull towards the center contributes to the overall stability.

Gargoyled Tetra

After finding some many 'merging' structures in my latest tensegrity experiments, I revisited also the idea of the merkaba. The study has some flaws to it, yet it would like see a much larger build to dismiss this concept.

Merkaba study

Surprises

My latest strategy to tensegrify objects with a pseudo-corner linking tendons yielded some surprising results. Like mentioned in the last blog, it reduces the total amount of string required, although it might take a bit more time to prepare all components. Building models with those already joined tendons was surprisingly easy, however, precision is paramount, and especially on smaller scale tricky to achieve.

When things come together nicely, magic seems to happen. The shot shows an icosahedron with braided nylon string (not really stretchy), flattened and held together by a paper clip. I was very hesitant to push this model to the limit, yet couldn't stop once it bounced back happily. A collapsible model with non-elastic string, which makes me wonder whether I can build collapsible models of other shapes that do the same. Well, as I have a bit more building material at home I'm not too concerned about having some breakage during the experimental stage.

I want to explore the effect (and potentially integration) of UV light on my structures. The results are already very promising, much better that the photo suggests. Most of the nylon string has already a fluoro colour, spray painting the struts as well could bring some dramatic effects.

Scaling

I used up my supply of recycled struts from my geodesic dome, well, the larger length. Fuller claimed that the ratio of strut to string length remains constant independent of scale - so far, my scaling attempts had quite some errors in it.

As I was curious whether I can use eight centrally joined tendon trinities to build a six strut icosa without any support than my body and dexterity, and furniture nearby. The symmetry of this structure made it so much more elegant (at least conceptually) than most other tensegrity builds. I prepared eight corner joints with three tendons each, based on calculating the string:strut ration from a smaller and larger model.

I even got fancy and used two different colours for the tendons, I hope the different qualities of the string used won't create problems later on. After only one minor hick-up the model came together nicely, with the length I measured being precisely what I wanted according to my calculations. I can imagine that even a bit less tension would provide a stable (not disassembling) model.

The tetrahedron survived some wild storms and still hangs in its slightly hidden space, while three other outdoor installations have gone.

Next big thing

I think I got sufficiently mad during the last week to call myself an artist. I upscaled to a degree that my calculations were quite off the target, and a lot of re-adjustment was required. Three structures with 95 cm struts emerged. The first one, attached to its current destination in a stormy night before the rain hit, still survives the wild weather. The second structure didn't stay for 24 hours in the wild, the latest one still needs some painting and still blocks some of my lounge.

While the tetrahedron exposes some efficiency in the use of materials (roughly a 1:1 ratio of string and tendon), the six-strut icosahedron seems wasteful. The initial string/tendon ratio was about 2.7:1, and as I was running low on nylon strings, I wanted more bang for my bucks. I can't really prove in any fashion that in order to create a tension triangle you can equally to from the corner along its sides or to its center, and the central joints introduced another additional node in the network of strings, but in practise it works just splendidly.

The six-strut icosahedron is a strange tensegrity, connecting the 12 corners of the icosa in a neatly way highly symmetrical through its center. In a way, the minimal 3 strut tensegrity can be understood as minimal octahedron. I better test this experimentally :) Being able to reduce to string/ratio to 1.5:1 made the idea of larger icosas much more viable, and I can't stop experimenting with the result.

I hit a sweet spot with the tendon lengths. Any three struts will balance (all 20 faces), drop and squeezing tests showed a lot of robustness, and the wigglyness can be hypnotising. I won't test it to breaking strength without camera, but I love the options offered by this design in a larger scale. It's simple to suspend small scale objects in the center, some sort of generic 'picture frame' to showcase more complex models.

I wonder whether I can use a set of centrally joined tendons to build from the scratch.

Bigger things

I recycled some of the struts I used for my geodesic dome experiment. With about 90 cm strut length 6 strut models of tetrahedron and icosahedron just so fit through my front door, my ambitions certainly outgrow my available work space indoors. 23 squared still hangs in a modestly visible spot from a tree, the storms of the last few days haven't affected it.

I have no idea about the effect sunlight will produce - typical Melbourne weathers meant grey skies since I installed it. But I found a perfectly suited spot for the next installation, an icosahedron, again with some parts of the struts spray painted.

The rain seemed to have stretched the tendons, I twisted some struts to increase the overall tension. I hope my idea about visibility works out, at night it's basically invisible. Hope the sun comes back to Melbourne soon.

Do or die

2012 started suboptimal when it comes to market appearances. Without the more complex sculptures, there's less eye catchers on the table. Who cares, I'm basically trying to sell art, so can't really analyse my success in business terms.

On the other hand, the lack of sales means I can come up with new projects what to do with tiny supply of rods I still have at my disposal. The source has dried out, just after I got a better idea how to work with the slightly heavier material than usual.

However, I experimented with a different topology for the tendons in the corner. Instead of connecting the tendons between neighbouring struts, I used a little ring to join them in the center of the corner. The struts have now an individual degree of lateral movement, and the cube happily balances on each corner. I also build an octahedron and the Vector Equilibrium in star formation instead of using loops for the corner.

As I enjoyed the different movement patterns with centrally joined corners, I went a bit bigger, attempting a hanging installation for outdoors. It survived already some strong gusts in its test location, it behaves quite nicely in windy conditions. The structure tends to rotate slightly out of the wind pressure, and doesn't swing itself up easily.

Octoids

I haven't been that busy during a week with building tensegrities ever, and I enjoyed it thoroughly. I needed models I could transport without a car. It will be lots of fun to find out how practical my idea of transport will be tomorrow, unicycling with a backpack from which twenty or so tensegrity structures dangle....

Besides a set of octoids, octahedra in which colours enhance aspects of their structure, I build a number of colourful icosahedra. I hope I can source more of the material I used for the latest icosa builds, it saved me lots of work. Doing the computer related things, like preparing and uploading the slideshow turned out much less pleasurable. Nevertheless, all is prepared for an interesting market day tomorrow, including the update of the market datea for the first three month of 2012.

The next season

Many things happened since I last had a stall at the Rose Street Market, most unfortunately, my car got totalled so I now face the challenge to transport enough models either on PT or on a unicycle.

As most of my toy octahedra were gone, I prepared the components for another batch of octoids, spending lots of time on sawing, cutting and a bit of spray painting. Luckily, I didn't forget how to build tensegrities, determined to produce enough portable material for next sunday's market I got into a bit of a rush - six octahedra, one icosahedron and one cube provide the first yield of two days work.

By chance I came up with a new colour combination for square struts, which works amazingly well. I might need to prepare another batch of struts to use up all the coloured ones I have now, and getting the photo and documenting job done.

I nearly forgot the joy of bringing tensegrities to life, especially those with unique looks.