To model joints in the human body such that the individual bones do not touch one another, enclose the entire structure in a fascial sleeve which acts as a compression system. Myofascial wrappings act somewhat like helicial tensegrity masts. Tensegrity provides a simile, not a metaphor.
Context: Tom Flemons Archive
Images of masts and weaves.
Tensegral weave patterns encase each joint
(June 6, 2014) Buckminster Fuller mentions in his book Synergetics that Tensegrities are pure pneumatic structures. So yes a Biotensegrity theory of human structure would necessarily mean we are looking at the hydrostatic pressures in the body. A single compression strut that models for example the femur in the body is inadequate to describe how tensegrity in the body works. I’ve used single struts in this way as a form of shorthand to build my models easily. But I’ve long believed that individual bones need to be modelled as tensegrity structures themselves. So a better way to model a leg or arm for example is to build a tensegrity mast which functions as a compression strut that replaces a single femur strut but also models the hydrostatic pressures in the entire leg. My more recent models of legs have this feature. (see attached images).
I also believe that the only way to successfully model joints in the human body such that the individual bones do not touch one another is to enclose the entire structure in a fascial sleeve which acts as a compression system. A fascial compression sleeve can be modeled as a spiral tensegrity mast. Thus my most recent drawings show a tetrahedral or octahedral tensegrity mast enclosed in a spiral tensegrity mast. (see attached image).
As for how you wire all of this together… As Vytas has pointed out any muscle attaches in multiple locations along a bone via the periosteum. Thus I would think you can make multiple attachment points along a bone similar to how membranes can model tensional forces more comprehensively than single lines (see attached image).
(June 6, 2014) Sure, forward our correspondence and any images to anyone you think might be of help. I suggest as well, that they take a look at my paper The Bones of Tensegrity found on my website. In this paper I make the argument for fascial sleeves as compression elements in the body.
Tensegrity Levers (July 2015) Tensegrity systems can be described as floating interconnected levers operating without fixed fulcrums in networked arrays. Looking for equivalent structures in the body, we find bones coming together with muscles, ligaments and tendons crossing and securing the joint, and with fascia wrapping each component and the entire joint latitudinally and obliquely in a complex multi-tiered manner. Something very similar to a tensegral weave pattern connects everything via the periosteum to the bones. A simple model of this is a double spiral tensegrity mast.
You can see how each strut is linked via slings such that the entire structure supports and transmits forces as a collection of first class levers. The fascial weave that wraps and passes over each joint could be described in the same way and account for why our joints are so much stronger than third class levers should be.
Changes to prestress allow joints to be alternately stiff or yielding, as discussed in The Need for Levers with Floating Fulcrums.
Myofascial wrappings act somewhat like helicial tensegrity masts
(March 9, 2016) For the concept of biotensegrity to be useful at the level of structural anatomy then myofascial wrappings must be understood to act somewhat like helical tensegrity masts i.e. able to act as compression sleeves as well as extend under tension like helical springs.
It’s my strong opinion that long bones can only be said to float in the myofascial matrix and revolute joints be included in the definition of possible tensegrity configurations if we can describe the anatomy of the body to be linked like tensegral masts knitted together to form a woven whole.
Tensegrity provides a simile, not a metaphor
(March 9, 2016 continued) I want to be careful how I use words here – I mean the body is put together somewhat like a woven linkage of helical tensegrity masts. We need to talk in terms of similes not metaphors. Tensegrity structures are not homologous with biological structures.
( wikipedia: In the context of biology, homology is the existence of shared ancestry between a pair of structures, or genes, in different species. A common example of homologous structures in evolutionary biology are the wings of bats and the arms of primates).
Also tensegrity forms do not equate with biological forms. My leg/knee/foot model acts a bit like our bodies (function) but the form is only slightly similar and in some cases not at all. My most recent leg/foot for example doesn’t have a femur, tibia or fibula – rather I used elongated 4 fold tensegrity prisms and joined them with a complex revolute joint which is also composed of two more 4 fold tensegrity prisms. In this sense I would say that tensegrities can be analogous to biology but are not homologous. Confusion at this point has led to much misunderstanding. For example there are no icosahedrons floating around in the body, vertebrae do not stack together like a tetrahedral tensegrity mast, and bones do not float in isolation in the same way that struts in a tensegrity do.
(June 7, 2016) I’m perfectly prepared to say that the body behaves like a tensegrity (simile) – the map, but not that it is one (metaphor) – the territory. There are structures in the body that may act in ways similar to tensegrities e.g. myofascial tensional meshes that wrap joints perhaps can be compared to helical tensegrity masts. But the complex chaotic wrapping of fascia over and around joints looks nothing like a tensegrity mast – I’m abstracting out tensegrity principles that might account for how joints can float. Also I think I made a good discovery that the structure of the pelvis bears a close resemblance to an octet truss – yet no one has ever made any comment on this. I can see the pattern but then I’m a geometer and there don’t appear to be any anatomists or biomechanists that are trained in geodesic math – so no one has recognized the implications. I could write a whole paper on the implications but who would understand it if they can’t see hidden structure?
Videos of weave encasing a joint
(Aug 29, 2015) A tensegrity array can act as a weave encasing a limb:
A leg/foot model with tensegrity weaving
Tensegrity mast as an envelope for a non-tensegral joint
(Aug 29, 2015) This woven tensegrity braid bends when actuated. Without the dowels the bend is gradual and sinuous. With dowels inside, the angle is acute and sharp.
Video of tensegrity arm with saddle sling elbow
(Aug 29, 2015) A model of two long bones (e.g. in arm or finger) inside a spiral tensegrity woven braid. The joint model: two Y shape ends at 90° to each other, connected and suspended by a tensioned saddle sling. Unrestrained, this functions essentially as a universal joint. With longitudinal restraints it functions as a revolute joint that is not hyperextendable (range of motion no greater than 180°).