Ashley D Goodenough: "Lyretail" Prosthetic Accessory

Concept:

My focus for Digital Fabrication this semester is the study, design, and fabrication of various prosthetic accessories for specific uses. My first project, which is for a below-knee accessory, will be a prosthetic accessory for scuba diving. I’m calling it Lyretail (or alternately, Scalefin), because my main inspiration for the form comes from a family of gorgeous saltwater fish called Lyretails, also sometimes known as Scalefins. It’s also a fun play on words, and I’ve become endeared to it. There are many variations of the lyretail, but they all have exaggerated and slightly asymmetrical tail fins, and their coloring tends to be dramatic. My goal for this design is to make a diving prosthetic that echoes the streamlined and elegant forms of oceanic fish. The flipper will be similar to a split-fin in that the paddle will not be a solid piece - it will be for diving in conditions where the tide is less strong and unpredictable and you want a little more fine control of your movement. The lower leg portion of my concept draws from the shape of the wings of a manta ray.

From my research, I’ve gathered that a single-axis foot is what most people want from a scuba prosthetic - this way, the foot/fin only moves in one plane and has a predictable path of motion. Another need is ease of attachment and detachment of the flipper to the prosthetic foot, which in most cases is a Sach foot. Given the limited availability of dive prosthetics out there, it’s fair to say that another desire is more customization of the shell to suit your personal style. With these main ideas, I started concepting the Lyretail. When the model is finished, I plan on the ankle joint being a single-axis of my own design. It will ideally be able to lock in 2 or 3 positions, using some sort of manual dial. Additionally, the flipper will either be modeled in a way that means it can be easily slid onto a foot underwater and tightened around the heel, or it will be modeled so that if it were printed in a flexible and water-safe material, it would be simple to slip on the Sach foot and over the heel. The top leg portion will be completely separate from the flipper, but will be connected to the joint and the Sach foot design that fits into the flipper. 

In addition to my online research of scuba prosthetics out there currently, I also interviewed a family friend who is a recent amputee and a dive master. We met and talked about how his dive prosthetic works, and how I could go about making my final design effective but still appealing. He agreed with the need for a single-axis rotation in the ankle, and liked the idea of a locking mechanism - he’s actually been designing something similar recently for his own use, since he’s an engineer by trade - and the need for the flipper to be easy and fast to put on and adjust. I learned that I either need to create a leg design that is a completely functional underwater prosthetic that can use a vacuum and pressurization to stay attached, or my design must be purely a surrounding shell that can fit around an existing prosthetic. I haven’t decided which direction I’m going to go with that yet. He emphasized as well something I need to generally keep in mind in this business: every single prosthetic or prosthetic accessory is designed for a particular person, because everyone’s situation is going to be a little different - height, weight, amputation level, etc. I’m going to keep meeting with him when I have questions about ways to make my design more useful, or if I’m uncertain about my design interfering with its overall effectiveness.

Modeling (so far): 

My modeling deliverable at the end of the first four weeks of the semester was to have a clean, preliminary model of my prosthetic last; I would have the main form ready to go, and have very little detail. I got a little further than that, but may have to backpedal after talking with my friend and learning about how his personal diving leg works. I started scaling my concept drawings to each other in Photoshop and setting up some visual guides so that I could bring some orthographic views into Rhino and use them as a reference. I used PictureFrame to set up my front, side, and top views. I used Control Point Curves to first build the side silhouette of the leg and flipper together, then the front silhouette, creating only vertical curves for now. I also used my top view concept of the flipper to curve out the shape of the sole. Then, using Interpolate Points Curves, I drew horizontal curves to basically act as defining curves for the shape of the leg and flipper. I needed quite a few, since the flipper was more complex than a normal foot last would be. I used Rebuild to reduce the complexity of my curves, and made sure I still had intersection where I needed it. Using CurvatureGraph, I tested the continuity of my curves to make sure I was going to build a surface that was relatively smooth with curves that were continuous after I had been splitting and joining them. Before I used NetworkSrf to create my last, I split my vertical curves at the ankle, so that I could have separate surfaces for the leg and flipper, given that the leg could be a much simpler surface if I rebuilt it separately. Then, I selected all my curves and used NetworkSrf to build a loose surface. The flipper turned out to not be incredibly smooth, no matter how much I refined my curves (with RecordHistory turned on), so I turned on control points and sculpted it for a while just by manually moving points around (MoveUVN). I also used SetPt to align my loops to get a smoother surface, and Zebra to test my UV stretching. In the end, I also ended up using ExtractIsocurve to pull some new curves from the surface, and then rebuilt again using those slightly better shapes. Now that I had two surfaces, I could start refining. I used Interpolate Point Curves and Interpolate on Surface Curves to mirror my concept art from the side view, then projected my curves onto the surface. I used Trim to remove the parts of the surface I didn’t need anymore, but kept a copy of the original surface in case I paint myself into a corner later and need it back. Once the top of the flipper and the leg were trimmed, I used OffsetSrf (with Solid checked) on the leg to make it a closed polysurface with a width of a little over 1/8 inch. I FilletEdged every edge to almost the same radius. I attached the pole to the open leg design using some fancy cylinders and DupEdge to mimic my current shapes and a BooleanUnion/Boolean2Objects combination. For the flipper, I used my own foot last design to build an inner hole, then used BlendSrf to connect the two at the top. I used Patch to close up the bottom of the flipper, but had some cross sections to assist it in being smoother. Since that patch wasn’t quite lining up with my flipper and I needed to clothe my naked edges, I used JoinEdge to close the tiny gap.

Materials: Given that the model is not complete and separated into its component pieces yet, I'm holding off on deciding on materials. My favorite idea right now is to mimic the coloring and patterns of the batfish, and use a rubber-like material for the flipper and a hard plastic for the leg (the hard molded part of most prosthetic legs is made of carbon fiber):

References:
https://www.media.mit.edu/videos/ceb-2016-05-06/
http://biomech.media.mit.edu/#/

https://www.northeastern.edu/rise/presentations/triton-scuba-diving-prosthetic/

http://www.bizjournals.com/twincities/blog/in_private/2012/11/meet-the-scuba-leg.html

http://www.scubadiving.com/article/news/what-its-dive-double-amputee

http://www.palmbeachprosthetics.com/Stories-dive-buddies-part-iii-14.html

Alec McKay:Prosthetic Accessory: Polygo Modifications

After our critiques on Monday, I decided to make some changes to my prosthetic accessory. While the concept stayed much the same as before, there were some additional modeling techniques and changes to materials.

Modeling Techniques and Changes: Polygo now has a thinner shell design, which I created using an Offset Surface on my existing shape. I also removed one row on the inside of the leg so that the wearer can remove their accessory more easily. To do this I exploded the model and removed some faces before doing the Offset Surface. I also added a clip on the inside wall that can fasten the shell onto the pole of a prosthetic leg. 

Material Changes: To add more visual interest to my prosthetic accessory, I added onto the color palate with a new design. Colors gradating from yellow to red-orange form stripes down the leg. Polygo is made from plastic with a matte paint finish.

Thomas Perugini: Midterm Prosthetic Accessory

Concept: The idea behind this project is to emulate medieval leg and foot armor. While it draws from European armors of history, it remains within the proportions of the human leg, creating a more streamlined, and less bulky aesthetic. Inspiration mainly comes from sets of German Gothic knight armor. The name "Sabaton" is derived from the name of a knights foot armor, the sabatons.

Strategies: The general forms of the shin and foot were created with curve networks. The buckles are filleted curves that were extruded, and circles fixed on either side. The strap is two rectangles that were swept along a rail on the back of the boot. The purple plates on top of the base shape were made from larger versions of the leg/foot, but with many portions trimmed away. The bolts on the sides are spheres.

Materials: To keep with the lightweight and easily accessible material, much of the prosthetic is hard plastic. The belt is leather, and buckles are a rough brass metal.

Austin Bower - Prosthetic Accessory

Gundam MK1 concept: I got the idea for this model for one of favorite TV shows as a kid.  I wanted to design one prosthetic more robotic then the others. This model was designed to fit tightly on the knee joint of the prosthetic and not to be removed

Spiral concept: This model was partially inspired by the old glass coke-cola, but otherwise I was just going for a nice spiral look so the prosthetic would not have sharp edge.  

The Knight concept: The original thought behind was based off a MTG card, then I was just going for a knight's armor look.

The Warrior concept: This model started out as just trying to be a stream line design, but i did not like how it turn out so i changed it for more of a samurai style. The other idea is that each side can be switch around for an asymmetrical  look

Technique: I created all models in Maya. Most of the models where does the a series of extrudes, blend deforms and twist deforms. One was mold form several planes by moving vertices into place.  Then I moved them to Rhino to apply the materials 

Alec McKay - Prosthetic Accessory: Polygo

Concept: I started out looking at some unique shapes for high-heeled shoes, and I found some that used polygons in interesting ways. This inspired me to make my boot, which later evolved into a prosthetic cover for just the shin, through experimenting with polygonal shapes and how they fit together. The shape is intended to be simple, fun, and suitable for casual or active wear. Polygo is a play on combining the words “polygon” and “go,” to signify both its angular form and its energetic feel.

Modeling Techniques: I began creating several iterations of the prosthetic by playing around with shapes in Rhino to see what things looked like.  Once I settled on a shape I liked, using heptagons going down the leg in a zig-zagging pattern, I used Sweep to fill in with surfaces the shape I had built with curves. Previous versions of my prosthetic gave me a lot of trouble when it came time to chamfer the edges, and there were a few lessons I learned from that about both patching holes that can be left from chamfering, and creating shapes that are easier to chamfer. For the inside of the prosthetic, I built a new shape using circular curves and Sweep rather than using Offset, since I wanted it to be hollow but the inside didn’t require the same design.

Materials: Polygo is made from rough, hard plastic so that it can be durable, light weight, and more scratch and smudge resistant than shinier finishes. To accent the dynamic shape of the prosthetic, I chose a bright yellow color with black lines that accent the edges. The top, bottom, and inside of the prosthetic is colored in the same black color as the accent edges, so that the yellow contrasts well against the rest of the prosthetic.

Eric Lam - Prosthetic Accessory: Striated

Concept: For my prosthetic accessory, I chose to create something that looked similar to human tissue, more specifically striated muscle tissue. It doesn't look exactly like striated muscle tissue but it's what I imagine whenever I think of muscles. My accessory is also inspired by games and animations that show body enhancements through synthetic muscles.

Technique: I used picture frames to create references to my front and side views of my sketches. I traced the outline of my accessory with curves from both views and used sweep2 to create the basic shape. I turned points on to fine tune the shape. After fine tuning, I selected the shape and used the smash command to create a plane that looked like an unwrapped version of the shape. I created the "muscle fibers" of the accessory, extruded pieces, cut pieces with boolean difference, and finally used flowalongsrf to place the design onto the accessory.

Materials: For the materials I chose mainly plastic for the sleeve. Black rough plastic for the main shape, soft rough orange and yellow for the details in the middle, and shiny red plastic for the "muscle fibers" to bring it apart from the rest. The foot is black carbon fiber since it's supposed to be strong, flexible, and light weight and the pipe is aluminum.

Ashley D Goodenough: "Exogenesis" Prosthetic Accessory

Concept: “Exogenesis” is the idea that life on Earth could've begun somewhere else in the universe. The design concept for this lower leg prosthetic accessory sprang up from a combination of aesthetic ideas that meshed well together after a lot of trial and error: plant cell structures and various cyborg and living machine concepts in media. From the combination of these two came something that reminded me of advanced, mechanical life, and that became "Exogenesis." I enjoy finding interesting ways to combine organic structures and patterns with human-made fabrications. This prosthetic accessory is split into two parts, a lower leg section and a separate but complementary shoe that can be used if and when you want. 

Modeling: Modeling the accessory began with getting a very simplified starting surface from clean curves. I used interpolate points curves on surface as well as off. I also used offset curves and Curve2View to get the foot shape I wanted. Using snaps, I connected a shoe sole curve to four side curves and then to a top curve to create a boot-like opening at the top. To ensure a smooth surface, I created a few cross sections in problem areas. From there, I rebuilt all curves and used curve analysis, made sure they were all connected, and used a network surface to create the last. I used CreateUVCurves and FlowAlongSurface (plus planarSrf) for many of the detailed cutouts, but also used basic curve projection when that tool wasn’t getting the results I wanted. I used DupEdge when I needed to retrieve a curve I’d lost. I used all varieties of Boolean, Split, Explode, Join, Sweeps, Lofts, OffetSrf, Trim, and Untrim to make sure I was keeping a watertight object and not creating naked edges. As always, there was plenty of filleting to keep me busy.

Additions: I added supports to the prosthesis itself to show how this accessory would be attached to an ankle joint. The following renders show the new joint and prosthetic foot, as well integrate my concept art with the new renders.

Materials: I used mostly metallic Axalta Paint materials for my prosthetic, because I wanted it to feel bright, lively, and machined. The color palette was monochromatic at first, then I branched out into some analogous ideas. Eventually, I landed on a combination of mostly metallic colors and one flat: flat white for the accent tubes on the ribbons, lime for the ribbons themselves, dark turquoise for the large sections, and a color resembling goldenrod for the prosthetic pipe. My added prosthetic pole and foot are the same goldenrod color, and the joint is ruby red.