Rope and Sound Interactive Tensegrity Sculpture

A unique interactive musical harp using electronic sensing rope technology. 

This piece originally appeared as part of the Extreme Textiles exhibit at the Smithsonian's Cooper Hewitt National Design Museum in 2005.  During 2006 it was installed in the main lobby at Pixar.

This piece is currently seeking a new home in a museum or similar location!
Please email dan-at-MonkeyLectric-dot-com if you can help.

HOW TO PLAY THE HARP

• Grip any blue rope near the center of the rope
• Pull hard to make a sound!
• Each rope makes a different sound (listen to the mp3 file below)
• Watch the display screen when you pull

ABOUT

• Conductive fibers are braided with traditional fibers to produce a patented rope technology that is capable both of carrying a load and monitoring the weight of that load.  The rope acts as its own strain gauge, monitoring tension constantly while the rope is in use. In this installation, changing the tension in the blue sensing ropes creates an electrical signal that modulates the music that you hear through a synthesizer. Just as the human muscular-skeletal system is a tensegrity of muscle and bone, the ropes and aluminum tubes form a tensegrity of tension and compression, pushing and pulling, weightlessness and gravity.
• Based on Tensegrity structures. The three main struts are held in place only by the tension of the ropes, they are not attached to each other or to the floor. A "standard" three-strut tensegrity of similar form has nine ropes required to hold it up. Here we have replaced each of those nine ropes with a spline of twelve, resulting in 108 total ropes. The resulting structure is surprisingly sturdy, it can easily support hundreds of pounds from the top end of each main strut with negligible deformation.

SIZE

• 9 feet high, 8 feet wide, 8 feet deep (dis-assembly is possible for transport)
• approximately 300 pounds
• three main struts are 12.5 feet long, 5.5 inch diameter.

MAKE YOUR OWN!

You can build your own non-musical model of this structure in just a couple hours.  All you need are 3 sticks, a roll of string and a drill.  (see the last step of the instructable)

Step 1 Construction overview

This instructable is intended to show you the inner workings of the sculpture and some of the challenges involved in building it. 

Comments

[Speedmite]

This look cool. It took a bit for me to realize what this is. I thought it was small...

But this looks great, I just wish that there was a desktop version, even if it didnt play.

[dan]

you can make your own non-musical one, no problem! all you need is 3 sticks, a spool of string, and a drill. drill 3 rows of equally spaced holes down the sticks (lets say, 3 rows of 12 holes). cut string into 9 pieces. feed the string through the holes. the models we made in step 4 are done just this way. you may need to have a 2nd person hold the 3 sticks in about the right orientation while you feed the strings through. i think i'll add this as a new step.

[cloverstreet]

This thing is amazing up until the part where you change hi-rezolution naturally complex signals into midi to trigger recordings of other instruments. You should be using models for re-synthesis instead. Then it will become more like a real instrument instead of another beautiful sculpture that mimics a midi-controller from the 80's.

I might like to help with that part, if you are interested. Thank you for the great instructable!

[dan]

yes that would make it better. we didn't do that yet because it is much harder than for a normal stringed instrument. metal instrument strings are very good at having a predictable response that changes consistently depending on the strength and timing of the plucking. the response of our ropes varies a lot given the same input stimulus. this made it a challenge just to reliably detect that they were plucked at all.

[randomray]

Cool sculpture , great idea . Just one thing your sculpture is based on one of Kenneth Snelson's designs . Bucky was pretty smart and cool and all that , but he got his idea from Snelson . Really look it up . Bucky was a shameless self promoter . LOL

[dan]

oh thanks, i added a link to that.

[buteomont]

Ok, I'll be the first to ask - how much did this thing cost to build? It's a nice piece of artwork, but it had to be expensive!

[dan]

About $10,000 in parts and materials. Labor not included.

[JamesRPatrick]

Dayum.

[wtf is 555]

Lol, too much $$$ for musical jump-ropes tied to a girder.

It's nice though.

[dan]

i've seen lots of times where a bunch of paint smeared onto a piece of cloth costs over $1 million. i mean really!

[hammer9876]

You know, you have a point there. LOL!

[Rich99]

begs for a vid of sculpture in use w/ good sound...

[steveastrouk]

Nice work, a bit out of 'iblers usual league, but nice.

Is the rope commercially available ?
Steve

[hg341]

yo uneed to do an 'ible on that sweet braider you have...
cool 'ible and nice art

[shanemac]

(removed by author or community request)

[Kiteman]

It plays sounds when you pull the ropes.

[reedz]

A bell?

[Kiteman]

Electronic sounds, I think

[dan]

there is an mp3 on the 1st step. it plays lots of different sounds and notes.

[porcupinemamma]

Wozers! Talented man