Upon searching, on google of course, for cellular scaffolding I stumbled upon the Wiki article for tissue engineering and additive manufacturing which took me down a rabbit hole. I soon found out about Dr. Anthony Atala, M.D who has already started 3d-printing kidneys. What? This happened 3 years ago. I feel so out of date. Anyway, they are printing cells in some kind of pink gel using a gel extruder which looks to be pneumatically controlled. This is how our first paste extruder is going to operate. We have already ordered most of the parts, it's just a matter of finishing the plan and making the time!
Bioresorbable polycaprolactone has been shown to work great as a medical stint.1 The Scientist has a great mini review of 3d-printing entitled, "Organs on demand"
Monday, September 1, 2014
Tuesday, July 29, 2014
Open-Source Stereolithography (SLA)
Stumbling around later-than-should-be-up on the internet, I found this slideshow presentation. Looking past a lot of grammatical errors, there appears to be very valuable information for 3d printing makers in the open source movement, specifically for FDM (fused deposition modeling) and (SLA) Stereolithography apparatus 3D printer specifications:
I have noted a few companies that sell consumer-level SLA 3d printer.
3DS offers full-color powder-fusing inkjet machines that fuse nylon powder together and color it for you in one step using a printhead.
I have noted a few companies that sell consumer-level SLA 3d printer.
SLA 3D Printers:
Formlabs Form1:
Formlabs has created the Form1, this is the first SLA 3d printer I saw in person when I visited Autodesk's campus @ Pier 9 in San Francisco. I was given a personal tour by my girlfriend's friend. You gotta love making connections with new people. The print is created upside down on a tray.d9-asdf
The print is created upside down again on a plate coated with polydimethylsiloxane (PDMS) which undergoes a sequential dipping and curing process using a z-axis screw and modified high-definition video projector. (the modification is likely the bulbs3D Systems: Projet 1200 SLA
3D Systems (3DS) has been in the additive manufacturing business for quite a long time compared to most other 3d-printing companies. Most 3DS machines are workhorses with large build volumes, meant for industrial prototyping. 3DS offers SLA printers which cure acryllic monomeric resin to make a variety of hardnesses, anywhere from flimsy rubber (Shore 40ish) to hard plastic (Shore 95+). These printers use a nozzle to deposit support and resin mixtures simulateneously, typically these prints are not colored. This model features 585 dpi and 30 micron layer resolution. At $4,900 it is considerably cheaper than any 3DS printer I have asked about. Unfortunately, it uses a proprietary plastic.3DS offers full-color powder-fusing inkjet machines that fuse nylon powder together and color it for you in one step using a printhead.
Friday, July 11, 2014
Our First 3D Printer - A Lasercut RepRap Mendel (Techzone Remix edition)
By us, I mean James Mitchell, Kevin Takalo and I. Currently, we've decided our company name is going to be Hedron. Here are pictures I've compiled of our first 3d printer. This printer came as an incomplete kit, with decrepit generation 3 electronics which we swapped out for Generation 6 electronics pictured below. We then upgraded to RAMBO v1.2 electronics to support a heated bed and made numerous other modifications and upgrades to it. We still continue to make improvements because it is still working well! I will continue to post updates on what we are making. There is still a lot I have yet to document. Enjoy these pictures, they are displayed chronologically starting from the top.
Time lapse video of the printer working is made with 'VideoVelocity
Free' software and a Mcnally IceCam 2 Webcam. they are meant to fit together to form one big tetrahedron (out of PVC).
This is some of my first time-lapse video footage.
Second print of the left eye-piece used a raft for better adhesion, a raft is a few layer solid cushion used to increase surface area and flatness for the part (10mm raft outer margin), but this still detached due to warpage.
Third Test print was also a failure due to lifting. (10mm raft margin).
I applied an ABS-Acetone slurry, composed of 1:1 acetone:ABS scraps thoroughly mixed and dissolved, on top of the Kapton tape with a small paint brush for The Fourth Test print (30 line brim width) and this time the print successfully stayed stuck to the bed. In fact, the print stuck so well to the slurried kapton that I had to rip the kapton tape off to get the print off the glass top.
Steampunk Goggles using 52mm Photographic Filters by guyc is licensed under the Creative Commons - Attribution license.
Owl statue by cushwa is licensed under the Creative Commons - Attribution license.
Notes:
We made a heated print platform out of acryllic aluminum, but after printing with it at ~90 degrees Celcius it warped considerably far from flat. Therefore, we took the advice from the Reprappro Tricolour wiki and sandwiched the heated PCB (Printed Circuit Board) between a 1/4" piece of MDF (Medium Density Fiberboard), which is used as an insulator, and a 3/16" piece of aluminum sheeting, which is a heat spreader. I applied thermal paste to the top of the PCB (the side with the traces) and bolted the three sheets together at all 4 corners with some M2.5 cap screws and nuts. Be sure to cut out the aluminum for the silver traces on the PCB to avoid shorting out your electronics and power supply.* The printer has now has gone through numerous upgrades including RAMBO v1.2 electronics, a 2 mm ID (inner Diameter) teflon bowden tube that connects the printed reprappro tricolour cold-end and the purchased all-metal tricolour hotend. So far we have printed: a plastic x-carriage for the hotend, a spool holder, plastic parts for a Reprappro tricolour mendel 3D printer, plastic parts for a Cherry Pi Delta printer, an iphone 5 bike mount, and some custom designed parts i.e. a silicone mold and trinkets.
*MK2 PCB Heated Bed shorting issue resolved. It turned out I was shorting the silver soldered contacts of the PCB with the aluminum heat spreader and causing the RAMBO v1.2 electronics to reset over and over. The Pronterface (printer interface) software data log displayed a code 'brown out reset' indicating a loss of power (in this case due to shorting). I plugged in the multimeter and measured the resistance of the heated bed between the + and - contacts and found 0.3 ohms. This bed should have a resistance of around ~2 ohms between the + and - contacts and around 4 ohms between the - contacts. After cutting out some of the aluminum for the contacts the heated bed is getting up to 90 degrees celcius (a measured value) in about 5-10 minutes. The thermistor is reading about 10 degrees too high. I have not calibrated the thermistor yet.
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This is the printer when we first got it working |
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You can still see the wires are hanging out bare |
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Some of the first test extrusions. The yellow film is Kapton tape (polyimide film) which helps the plastic stick, the green stuff is PLA plastic (polylactic acid), a corn-based plastic that supposedly is biodegradable |
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Some initial problems we had skipping steps. Offsetting of the layers occurs when the stepper motors skip electronic pulses (steps), or when a belt skips, or when there is binding in the railing. We thought this was due to overheating, so we installed 12V cooling fans and aluminum heat sinks on the stepper motor housings. |
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This neon transparent PLA came as a 1kg roll of filament (1.75mm), we hope to be producing our own types of filaments in the near future. |
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We started with a very simple 20 mm x 20 mm x 10 mm cube to get our axes "steps per mm" values set in the firmware. Currently, we are using Marlin firmware. |
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We had insufficient infill, this was a matter of getting the extruder 'steps per mm' value calibrated in the firmware |
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One of the first bed of ABS parts made for the next 3D printer (RepRappro Mendel Tricolour). You can see the MKII PCB (Printed Circuit Board) heated bed we added. |
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We printed an upgraded Reprap Mendel x-carriage, and upgraded the hotend to the Reprappro tricolour Mendel kit (0.5mm) and made a custom mount for it. |
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This is a Reprappro Mendel tricolour-style heated bed platform (pictured here without the borosilicate glass top clipped on) |
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These are the Rambo v1.2 electronics we upgraded to control our printer purchased from Norcal electronics |
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Here we printed out the green and silver spool-holder arm. Filament spool holder for Prusa Mendel by mpluma is licensed under the Creative Commons - Attribution - Share Alike license. The bowden-style white cold-end (the part that feeds the filament) is from a Reprappro Mendel tricolour. |
Tetrahedron
I printed a tetrahedron that my designer friend, Kris Johnson and I designed together. There are wavy ridges in the sidewalls of most of our prints at this stage due to a phenomenon called "z wobble" (60-100mm/s). Initially, we thought it could be due to overextrusion while laying down the perimeters or slop in the gantry. The wavelength of the ridges is approximately 5 or 6 layers and is consistent from print-to-print. It turned out realignment of the x-axis rods, brearing mounts, and motor mount bracket fixed the z wobble.This is some of my first time-lapse video footage.
SteamPunk Goggles
First print of the left eye-piece failed because the bottom detached from the bed, due to warping of the print while printing. This happens if there is insufficient bed heat and/or adhesion. To increase adhesion we print a perimeter which can be seen around this print, called a brim. This print has a 20 line brim width. A setting we use in Cura, which is the software we use to control this printer.Second print of the left eye-piece used a raft for better adhesion, a raft is a few layer solid cushion used to increase surface area and flatness for the part (10mm raft outer margin), but this still detached due to warpage.
Third Test print was also a failure due to lifting. (10mm raft margin).
I applied an ABS-Acetone slurry, composed of 1:1 acetone:ABS scraps thoroughly mixed and dissolved, on top of the Kapton tape with a small paint brush for The Fourth Test print (30 line brim width) and this time the print successfully stayed stuck to the bed. In fact, the print stuck so well to the slurried kapton that I had to rip the kapton tape off to get the print off the glass top.
Steampunk Goggles using 52mm Photographic Filters by guyc is licensed under the Creative Commons - Attribution license.
Owl statue
printed at half scale, like most all of our prints, has some repeating lines and ridges in the sides from a problem termed "z wobble". Z- wobble is when the z-axis screw rods wobble in circular paths causing the x-chassis to wobble.Owl statue by cushwa is licensed under the Creative Commons - Attribution license.
Notes:
We made a heated print platform out of acryllic aluminum, but after printing with it at ~90 degrees Celcius it warped considerably far from flat. Therefore, we took the advice from the Reprappro Tricolour wiki and sandwiched the heated PCB (Printed Circuit Board) between a 1/4" piece of MDF (Medium Density Fiberboard), which is used as an insulator, and a 3/16" piece of aluminum sheeting, which is a heat spreader. I applied thermal paste to the top of the PCB (the side with the traces) and bolted the three sheets together at all 4 corners with some M2.5 cap screws and nuts. Be sure to cut out the aluminum for the silver traces on the PCB to avoid shorting out your electronics and power supply.* The printer has now has gone through numerous upgrades including RAMBO v1.2 electronics, a 2 mm ID (inner Diameter) teflon bowden tube that connects the printed reprappro tricolour cold-end and the purchased all-metal tricolour hotend. So far we have printed: a plastic x-carriage for the hotend, a spool holder, plastic parts for a Reprappro tricolour mendel 3D printer, plastic parts for a Cherry Pi Delta printer, an iphone 5 bike mount, and some custom designed parts i.e. a silicone mold and trinkets.
*MK2 PCB Heated Bed shorting issue resolved. It turned out I was shorting the silver soldered contacts of the PCB with the aluminum heat spreader and causing the RAMBO v1.2 electronics to reset over and over. The Pronterface (printer interface) software data log displayed a code 'brown out reset' indicating a loss of power (in this case due to shorting). I plugged in the multimeter and measured the resistance of the heated bed between the + and - contacts and found 0.3 ohms. This bed should have a resistance of around ~2 ohms between the + and - contacts and around 4 ohms between the - contacts. After cutting out some of the aluminum for the contacts the heated bed is getting up to 90 degrees celcius (a measured value) in about 5-10 minutes. The thermistor is reading about 10 degrees too high. I have not calibrated the thermistor yet.
Thursday, April 25, 2013
Building Community with Biomimicry: The Village Building Convergence (VBC)
My sister encouraged me to check out a Portland group of people who get together for several days, weeks or months every year to build community in their neighborhood. They have made at least 32 community-building gathering sites around Portland. Their activities range from painting streets and intersections to starting community gardens to building kiosks, covered benches and playgrounds out of natural building materials like cob, earthen plaster and straw bales. I will post pictures of this year's progress when I see it as I'm volunteering to help this year; this google image search shows some of what they have done.
Building community is important to biology because we, as a part of biology, thrive on shared physical resources and, like plants, we grow faster the more interconnected we become. Plants and fungus trade nutritional ions and soluble organics between each other (nitrates, amino acids, and many more) like we trade cash for groceries at the store only they do it in a much more sustainable way. Instead of needing to travel miles to the grocery store to get what they need, plants get it from proximate sources within a web of vastly distributed and entangled biomass; there can be miles of mycelial (fungal) networks underground. In fact, the largest organism is said to be the fungus Armillaria solidipes (formerly Armillaria ostoyes), also termed the "Humungous Fungus"; it is 3.4 square miles of fungal networks and astonishingly comes from Oregon's very own Malheur National Forest. A locally-derived sustainable web of resources for thriving life is a reality for biology and it's the backbone philosophy the VBC puts forth as it expands evermore into humanity's cultural realm; it is part biomimicry and part ingrained genius.
There are so many reasons why it's beneficial for us to build community, the connection and sharing of resources saves energy. In biology, plants are supported via their root systems to the soil and connect with each other to extract nutrients from the surrounding materials in the soil. The more symbiotic fungal networks they can tap into, the less roots they need to grow in order to get the nutrients they need, and the more sunshine and CO2 they can convert into sweet sugar. No wonder that millions, and maybe even thousands of years ago, biology was existing on a huge scale. Soil contains a lot of goodies for plants; it is derived from decomposed proteins, fats, sugars, clays, silts, sands, ancient marine life, and even dissolved air; things from the air include dissolved carbon dioxide as carbonic acid, nitrogen, and oxygen. Clays are a variety of nano-sized tectosilicate particles from 1 nanometer (nm) to 1 micron (1000 nm), approximately the size of proteins, that are suspendable in water.
Silts are micro-sized aggregates 1 micron to hundreds of microns of tectosilicates. Tectosilicates are minerals which include crystalline Silicon dioxide (quartz), feldspar, zeolites, and other awesome naturally occuring compounds and elements. Sands are macro-sized aggregates that I hope you are familiar with already. Other things in silt and clay include water, potassium, sodium, calcium, aluminates, magnesiates, and even more! Nature is ridiculously complex. When dissolved with water these aggregates become like porous hydrated spheres floating in an ocean of soil, like in the movie SPHERE,
exchanging charged ions and adsorbed organic compounds kind of like a space shuttle. Biology as a whole uses these materials for it's minature biochemical factories, also called enzymes.
Besides the awesomeness of using miniature factories, the mycorrhizae, or root fungus, acts to extend the absorption capacity of plants by over 1000 fold.
This picture reminds me of the human brain and the internet. So get out there and visit vbc.cityrepair.org if you're in Portland, or better yet start your own neighborhood takover and get your neighbors involved in building community so that we all don't have to work as hard to get what we want. For more fun related to biomimicry check out this video and then get involved in the movement! As a whole we can create beautiful intersections between roads, people, and plants using biology as our guide. Now you can consider yourself a newly appointed villager in your local city village and be merry!
Building community is important to biology because we, as a part of biology, thrive on shared physical resources and, like plants, we grow faster the more interconnected we become. Plants and fungus trade nutritional ions and soluble organics between each other (nitrates, amino acids, and many more) like we trade cash for groceries at the store only they do it in a much more sustainable way. Instead of needing to travel miles to the grocery store to get what they need, plants get it from proximate sources within a web of vastly distributed and entangled biomass; there can be miles of mycelial (fungal) networks underground. In fact, the largest organism is said to be the fungus Armillaria solidipes (formerly Armillaria ostoyes), also termed the "Humungous Fungus"; it is 3.4 square miles of fungal networks and astonishingly comes from Oregon's very own Malheur National Forest. A locally-derived sustainable web of resources for thriving life is a reality for biology and it's the backbone philosophy the VBC puts forth as it expands evermore into humanity's cultural realm; it is part biomimicry and part ingrained genius.
There are so many reasons why it's beneficial for us to build community, the connection and sharing of resources saves energy. In biology, plants are supported via their root systems to the soil and connect with each other to extract nutrients from the surrounding materials in the soil. The more symbiotic fungal networks they can tap into, the less roots they need to grow in order to get the nutrients they need, and the more sunshine and CO2 they can convert into sweet sugar. No wonder that millions, and maybe even thousands of years ago, biology was existing on a huge scale. Soil contains a lot of goodies for plants; it is derived from decomposed proteins, fats, sugars, clays, silts, sands, ancient marine life, and even dissolved air; things from the air include dissolved carbon dioxide as carbonic acid, nitrogen, and oxygen. Clays are a variety of nano-sized tectosilicate particles from 1 nanometer (nm) to 1 micron (1000 nm), approximately the size of proteins, that are suspendable in water.
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| Clays - SEM Micrograph Wikimedia Commons |
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| from http://www.thebeerdrifter.com/wp-content/uploads/2012/10/sphere.jpg |
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| Zinc-containing enzyme Human glyoxalase I (Wikimedia Commons) |
Besides the awesomeness of using miniature factories, the mycorrhizae, or root fungus, acts to extend the absorption capacity of plants by over 1000 fold.
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| Alberton, O., Kuyper,T (2009) |
Saturday, March 30, 2013
Geodesk's New Logo
This is an evolution of my logos
Here is a flower that reminds me of a crop circle
.jpg)
and then it turned into this
which is going to become something amazing someday
Wednesday, March 27, 2013
Thermal energy storage
Geodesk is all about researching ideas and developing useful products just for the fun of it. The current to-do list is long, but a high priority item is designing a solar reflector with parabolic mirrors to focus infrared through ultraviolet light towards a collector; a hollow pipe filled with a circulating absorption media. The water should get hot enough to produce free hot water except for the cost of the materials needed to build the system. Water pumps and cooling fans may be necessary safety features if the system is not designed for dealing with steam.
In line with Geodesk's mantra, a collector design that uses little or no newly manufactured, toxic, or non-biodegradable materials will be made. The design will attempt to incorporate a solar-electric tracking system to operate as efficiently as possible for the season and time-of-day. A neat blog called George's workshop has an article about a pretty sophisticated sun-tracking solar reflector here that uses vacuum tubes as the collector to increase efficiency in cold weather.
But what about hot water at night? Simple, cheap, and locally abundant materials with high heat capacities, like rock, sand, clay and water store a large amount of heat effectively. People have already figured this out. as you can see to the left is an attractive passive solar thermal mass called a water tube wall.
Hydronics is the practice of using water for thermal energy storage and has been in use in radiant floor heating for people's homes for decades and possibly even centuries.
Technically, a material with a high specific heat capacity (HC) will store a lot of heat given the opportunity, making a practical heat storage medium. Water's HC is 4.184 Joules per gram degree Kelvin, (it doesn't even need to be clean water), which is higher than most other materials.
Water can be pumped by a solar-electric-powered pump through a network of collectors and radiative tubing to heat floors, walls, air or water. Car or refrigerator radiators work well to radiate heat away from liquids and into the air. The car radiator works better with a fan so this could be setup to run from a low-powered solar-electric panel. The radiator can be contained in a ventiliation or circulation system in a wall, floor, or free standing to heat air.
Rock, tile, cement, and other insulators also make great thermal energy storage. Hot water can be pumped through tube networks in contact with the insulator to store heat. A trombe wall is an example of using passive solar directly without a hydronic network
Geodesk strives to design around basic principles: Materials we use and the waste we generate must be 100% recyclable and come from natural sources. By using natural materials, we are using sustainable nature-based design principles (also coined biomimicry or bionics). We are using up abundant and free resources and generating valuable products to benefit the environment and the community. For example, a large part of the Geohydrosolar system just mentioned could use materials already mined and mass produced for the automobile industries, destined for or already sitting in the junkyard i.e. mirrors, reinforced rubber hose (heater and radiator hoses), clamps, water pumps, heat exchangers (radiators and intercoolers), fans (both electric and pulley driven), and even gas tanks (mass storage). The geohydrosolar system could even be setup to purify water via distillation or run a steam turbine, all from using reclaimed materials and a lot of innovative design, research and rapid iterative improvements. Lastly, the geohydrosolar system can cool a hot house in a wet climate by using indirect evaporative cooling, this method requires putting a salt water solution under very high vacuum to make it boil at slightly below room temperature. Or, in dry climates, a hot house can be cooled using direct evaporative cooling, however this requires an abundant water source, which in dry locations can be scarce.
Enter the Namib desert beetle which can collect water on it's back in super dry climates, or maybe even Peruvian frog nets.
Another item on Geodesk's to-do list is designing a telescope for personal use. It could even be like the James Webb space telescope
In line with Geodesk's mantra, a collector design that uses little or no newly manufactured, toxic, or non-biodegradable materials will be made. The design will attempt to incorporate a solar-electric tracking system to operate as efficiently as possible for the season and time-of-day. A neat blog called George's workshop has an article about a pretty sophisticated sun-tracking solar reflector here that uses vacuum tubes as the collector to increase efficiency in cold weather.
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| Image obtained from George's Workshop blog |
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| Passive Solar Water Tube Wall Obtained from: https://www.thenaturalhome.com/img/waterTubeBlue2.jpg |
Hydronics is the practice of using water for thermal energy storage and has been in use in radiant floor heating for people's homes for decades and possibly even centuries.
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| A radiant floor heating manifold with hot (inlet) and cold (outlet) sides, the tubing is called PEX (Cross-linked polyethylene) |
Water can be pumped by a solar-electric-powered pump through a network of collectors and radiative tubing to heat floors, walls, air or water. Car or refrigerator radiators work well to radiate heat away from liquids and into the air. The car radiator works better with a fan so this could be setup to run from a low-powered solar-electric panel. The radiator can be contained in a ventiliation or circulation system in a wall, floor, or free standing to heat air.
Rock, tile, cement, and other insulators also make great thermal energy storage. Hot water can be pumped through tube networks in contact with the insulator to store heat. A trombe wall is an example of using passive solar directly without a hydronic network
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| A simple stone trombe wall. The downside to this design is the expense of the steel mesh. Obtained from: http://media.treehugger.com/assets/images/2011/10/trombe-wall-bluff.jpg |
Enter the Namib desert beetle which can collect water on it's back in super dry climates, or maybe even Peruvian frog nets.
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| Obtained from Wikipedia |
Another item on Geodesk's to-do list is designing a telescope for personal use. It could even be like the James Webb space telescope
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| James Webb Telescope Artist Impression Obtained From: http://www.mnartists.org/uploads/users/user_6887/5363167d0bcd619b207654457ca3497e/5363167d0bcd619b207654457ca3497e.jpg
Misc. Solar Thermal Notes, Links and Videos
Biodegradable film
PEX tubing manifold for radiant floor heating
cool write up on manifolds for solar thermal panels
DIY solar thermal with refrigerator heat exchanger (kinda ghetto)
video on hot water storage modular
a Thermosiphon
video on solar thermal air heating using gutter downspouts, osb/plywood box and shower door glazing
video on copper pipe manifold and corrugated galvanzied steel sheeting for DIY solar thermal water panels
video with good aluminum can heater
This guy uses ceiling insulation for a wood box container
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Tuesday, November 6, 2012
Taking design cues from crop circles
Geodesk takes inspiration from crop circles. It took hours to complete the glyphmimicry seen below. It was drawn by searching on-line tutorials for making a spider web using adobe illustrator. It's always the first time something is done that it takes the longest. The radius of the outer curved web lines is smaller than the inner curved web lines, clever designers the circlemakers are yes. Freddy Silva is the author of "Secrets in the Fields" the lower two images are excerpted from a Google image search that somebody published from his book, the top image is Geodesk's recreation of the genuine circlemaker's glyph. A future project is the Julia set and the sunflower pattern which is composed of rotationally symmetric golden spirals.
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