That's "Unnecessarily Complicated Hammock," and I've finally got the initial setup pinned together for test fitting and reinforcement. It at least looks a lot cooler than the first prototype
I'm an engineer, by trade, so generally I hate unecessarily complicated designs. But as a home-tinkerer, I find them an endless source of amusement . I came up with this idea a couple years ago, and even made an initial prototype when I was getting out of college, but got distracted for a few years . The idea is to get a hammock with two support points to approximate the "lay" of a Lay-z-boy recliner
Prototype 1
The first design was totally functional, and comfortable once inside. But, it was too snug in the shoulder openings, which made getting in/out a bit of a gymnastics challenge; you can only get out by doing a sit up while pulling your arms back . This time, I left the shoulder-relief cutouts much larger and I''ve incorporated a "bottom entry" type opening that doubles as a support for the seperate foot/leg boxes. I also reworked the suspension/load paths a bunch from the original design (which was basically a convoluted bridge hammock). Before, the tension supporting the upper spine went right through the "head basket" to the support cables, and squeezed my head annoyingly.
Now, one load path goes from the support point, along the spine, splits at the torso, and ends at the support cables on either side of the waist. Meanwhile, another load path starts at the other support point, splits just before the inseam (at the doorway), and ends at the support cables above the user's armpits. The place where these two paths cross forms a diamond shape beneath the torso, which should dissipate the load enough that the user won't feel like they're sleeping on a rope bridge . Complicated to describe, but I'll be reinforcing these high-stress load paths with webbing (once my order arrives) that will really make it obvious how the weight is carried .
Prototype 2
It's cold outside, so no, I'm not doing this on my patio, now . I apologize for the black-on-black color scheme of the hammock and dummy, which makes things less clear than they could be
It's kinda creepy, but the mannequin is a reasonably accurate form, being made of laundry stuffed into other laundry (), and gives a decent idea of how the lay is supposed to work. The user is supported by panels at the torso (just below shoulders), waist, thigh, and calves (heels and head, too, but the model doesn't have these yet). Between these areas, there is no support pressing on the user (joints, small of back, shoulders). Two cables/straps pulling up below the inseam (not at the inseam ) to the ridgeline serve to separate the legs and knees, and make for an easy/fast doorway to roll forward through (sort of like a vertical Hennessey door).
Right now, the shoulder-blades are painfully unsupported, but there will ultimately be two stirrups riding "sidecar" for the user to lay their arms in, taking most of the load off the shoulders. Some taut, stretchy fabric gussets beneath the shoulder blades themselves should then be able to support them comfortably, without sucking in tension from adjacent load paths.
I have the doorway held open with a pencil in this shot--you can see how it is tensioned closed by the user's weight
The purpose of the mannequin, for now, is to simply check that load is concentrating where I expected it, and to adjust shapes and angles to get what I'm looking for. So far it looks fairly good, but I think I'll have to rework the panel that supports the waist, as I'd expected, since I don't think it's wide enough (no jokes, now ) for my keester. There is a lot going on at that panel (splits and joins door opening, while carrying a lot of load), so I could only make a rough guess at what shape was needed. Another 2" or so of "web" and it should be perfect. The head and foot holsters are fairly straight forward, so I'll fit them last once the rest is finished enough for me to lay on (read: not held together with pins and twine )
I'll update this thread as I get everything attached to real suspension lines (and I become the test pilot ). If I don't get dumped on my rear, and the hammock appears to function as intended, I'll put up the patterns for the various shapes that make up the design, in case anyone else wants to practice putting grosgrain on convoluted edges. So far, construction hasn't been harder than my two Hex-Cat tarps, because all fabric pieces are so small and easy to work with.
TCB
(Okay, I must confess the amount of "engineering" in the design so far is something of a myth. At this point it's mostly a geometry experiment since I don't really know how strong the Joann's fabric I'm using is; some kind of light polyester taffeta called "silkessence")
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