From Plastic to Biomaterials: Prototyping DIY Electronics with Mycelium

Abstract

Researchers, makers and hobbyists rely on plastics for creating their DIY electronics. Enclosures, battery holders, buttons and wires are used in most of the prototypes in a temporal way, generating waste. This research aims to extend the boundaries of biomaterials applications into electronics. Mycelium is a fast-growing vegetative part of a fungus which adapts to different shapes when growing in a mold and decomposes after 90 days in a natural environment as organic waste. In order to create more sustainable prototypes, we use mycelium composites with common digital fabrication techniques for replacing plastic in electronics. We present our method for growing mycelium, our design process of using digital fabrication techniques with mycelium, applications for embedding electronics in mycelium boards, making enclosures for electronics, and using mycelium within electronics. This paper could contribute with the merge of biomaterials and electronics, an approach which is still under exploration.

Full text

Demo: From Plastic to Biomaterials:
Prototyping DIY Electronics with Mycelium
Eldy S. Lazaro Vasquez
University of California, Davis
Davis, USA
eslazaro@ucdavis.edu
Katia Vega
University of California, Davis
Davis, USA
kvega@ucdavis.edu
Figure 1: (a) CNC carving and Laser engraving tests. (b) Mycelium for embedding electronics. (c) Mycelium as a enclosure for
electronics (Arduino UNO and Circuit Playground) (d) Mycelium as an electronic component (Bio-breadboard).
ABSTRACT
Researchers, makers and hobbyists rely on plastics for creat-
ing their DIY electronics. Enclosures, battery holders, but-
tons and wires are used in most of the prototypes in a tem-
poral way, generating waste. This research aims to extend
the boundaries of biomaterials applications into electronics.
Mycelium is a fast-growing vegetative part of a fungus which
adapts to dierent shapes when growing in a mold and de-
composes after 90 days in a natural environment as organic
waste. In order to create more sustainable prototypes, we use
mycelium composites with common digital fabrication tech-
niques for replacing plastic in electronics. We present our
method for growing mycelium, our design process of using
digital fabrication techniques with mycelium, applications
for embedding electronics in mycelium boards, making enclo-
sures for electronics, and using mycelium within electronics.
This paper could contribute with the merge of biomaterials
and electronics, an approach which is still under exploration.
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the owner/author(s).
UbiComp/ISWC ’19 Adjunct, September 9–13, 2019, London, United Kingdom
©2019 Copyright held by the owner/author(s).
ACM ISBN 978-1-4503-6869-8/19/09.
https://doi.org/10.1145/3341162.3343808
CCS CONCEPTS
•Human-centered computing →Interface design pro-
totyping;Haptic devices.
KEYWORDS
biomaterials, mycelium, electronics; digital fabrication; bio
fabrication; rapid prototyping, DIY electronics.
ACM Reference Format:
Eldy S. Lazaro Vasquez and Katia Vega. 2019. Demo: From Plastic
to Biomaterials: Prototyping DIY Electronics with Mycelium. In
Adjunct Proceedings of the 2019 ACM International Joint Conference
on Pervasive and Ubiquitous Computing and the 2019 International
Symposium on Wearable Computers (UbiComp/ISWC ’19 Adjunct),
September 9–13, 2019, London, United Kingdom. ACM, New York,
NY, USA, 4 pages. https://doi.org/10.1145/3341162.3343808
1 INTRODUCTION
The use of biological materials as main components in design
has been explored in the eld of Biological Human Computer
Interaction [
16
]. Current research labs or maker spaces do
not have a recycling process and reuse several materials
used for making their DIY projects, instead waste is gen-
erated along the prototyping process, fails and iterations.
Bio-materials oer a more sustainable alternative to waste
due to their biodegradable properties. There are some ap-
proaches in applying DIY tools for biomaking [
4
], however it
was not proposed to merge biomaterials with electronics. In
order to select the biodegradable material that could be more

UbiComp/ISWC ’19 Adjunct, September 9–13, 2019, London, United Kingdom Lazaro and Vega
appropriate for this project, we compare the physical proper-
ties between the most common biomaterials to envision its
application in DIY Electronics (Tab. 1). We realized mycelium
is more suitable for DIY electronics applications due to it
is heat resistant, thermal resistant, light weight, shapeable,
hydrophobic, and it has degree of strength depending on the
substrate it is growing [
8
]. The mycelium growth is only part
of a mushroom life-cycle because there are no mushroom
spores or fruiting bodies involved in this process [
1
]. Fur-
thermore, using mycelium-based biomaterials for making
electronics’ enclosures, embedding circuits and creating DIY
electronics aid by digital fabrication techniques, are an alter-
native to replace common materials used for DIY prototypes
such as acrylic, vinyl, wood and plastic.
Table 1: Physical properties: comparison between dierent
types of biomaterials [3], [6], [14], [17],[8].
Property SCOBY Algae Bioplastic Mycelium
Degree of strength Yes Yes Yes Yes
Shapeable in real time No Yes Yes Yes
Thermal Resistant No No No Yes
Heat Resistant Yes No Yes Yes
Light weight Yes Yes Yes Yes
Hydrophobic No Yes Yes Yes
Compostable Yes Yes Yes Yes
2 RELATED WORK
Mycelium-based products have been manufactured in a di-
verse range of potential applications including acoustic dam-
pers, paper, textiles, bricks, foams (for packaging, and medi-
cal applications), and even for vehicles and electronic parts
[
8
]. However, most of the companies that have created these
various mycelium-based products keep the technology and
processes they use as a trade secret protected by their patents,
including the specic strain they use [10].
Start-ups and several companies have being creating dier-
ent mycelium-based products. Ecovative [
5
] have pioneered
the idea of using mushroom-based foam. Moreover, Dell de-
cided to use mushroom materials in its packing cases under
the eco-friendly fungi foam name[
1
]. MycoWorks [
13
] devel-
oped a mycelium-based bricks that could replace common
construction materials. MOGU [
12
] is currently developing
solutions such as resilient ooring, thermal and acoustic
insulation panelling, decorative elements and furniture com-
ponents. This company has also developed mycelium-like
leather and it is one of the few that describes part of its
mycelium growing process. Moreover, artists and designers
are also including these products in their creations. Aniela
Hoitink and Myco Design Lab created MycoTex, a dress made
only from mycelium discs [
15
]. MycoTecture [
2
] designed
an architectural installation with fungus blocks.
3 PROTOTYPING DIY ELECTRONICS WITH
MYCELIUM
Mycelium presents great attributes for intertwining it with
electronics. We used an already commercialized ’Grow-It-
Yourself’ Mushroom Material [
7
] which comes in a bag, to
start pushing the boundaries of the mycelium-based design.
After we grew molded shapes with various thicknesses nec-
essary for this research project, we used digital fabrication
techniques for DIY electronics implementation. Due to the
dierent recipes for growing and fabricating the mycelium-
based products, they could be created with dierent densities
and weight.
Figure 2: GIY bag and growing mycelium process.
Photo: CC0 Ecovative Design.
Biofabrication: Growing Mycelium
. First, we sterilized
the work area, measuring spoons and kitchen scales using
alcohol. Second, we added our and water in the bag and
follow all the instructions for mycelium activation which are
specied in the bag [
7
], and we stored it in a dark area for
about 4-6 days at a room temperature (27
◦
C or 80
◦
F). After
that time, the substrate will turn into a white color which
means the mycelium colonization was successful. Third, we
transferred the amount of material needed into a mold. The
mycelium material can grow into any shape or design. After
this step, we covered the mold with a bioplastic lm and
make some cuts in the surface to enable the mycelium to
breath. After all, we put the mold in a dark area for about
4-6 days until it becomes white again. Finally, we took the
grown parts out of their molds and put them into the oven
(80
◦
C or 194
◦
F) to stop the growing life cycle. This step is
basically to kill the mycelium and to obtain a nal bio prod-
uct. In summary, the growing process takes about 12-20 days
since the mycelium activation in the bag to the time when
the myco-composite piece is ready to use. This is a sample
of a mycelium growing process (Fig.2).
Digital Fabrication
. This research project compared the
three most common digital fabrication techniques using
mycelium: 3D Printing, Laser Cutting and CNC Carving [
11
].
We tested these techniques on the mycelium pieces in order
to open a new canvas for making DIY electronics. The CNC
carving and laser etching tests show the material behavior
under these techniques (Fig.1a). We also explored engraving
a circuit and laser cutting some shapes for embedding elec-
tronics on the bio-board. We found that CNC carving is not

Demo: From Plastic to Biomaterials: Prototyping DIY Electronics with... UbiComp/ISWC ’19 Adjunct, September 9–13, 2019, London, United Kingdom
the best technique for making electronic circuits because the
default material on the bag (hemp) is rough. However, this
technique can be used for carving larger areas for embedding
electronics. We used this technique for embedding a coin
battery into the composite material, then we traced a circuit
and lled it with metal leaf to have a conductive surface of
an LED circuit. Our last test, was lling the traced circuit
with gallium in its liquid state to create a switch which turns
on an LED. The line thickness in both tests was 3 mm., which
worked the best with the CNC carving technique (Fig.3).
Figure 3: Design 1: Coin battery embedded in mycelium.
Design 2: Gallium used on a myco-composite circuit.
Mycelium for Embedding Electronics
. The laser cut-
ting and engraving technique let us have a circuit layout
reference on the biomaterial surface in order to embed elec-
tronics after. We used 4 dierent materials for creating the
circuit: cable covered with plastic, metal leaf, conductive sil-
ver coating and wires (Fig.1b), (Fig.4). After testing these 4
materials, we realized that the rst 3 conductive materials
are more useful for electronics approach: cable covered with
plastic which has to be soldered to the components, metal
leaf which was embedded in the circuit paths by pressure,
and nally conductive silver coating which is highly recom-
mended due to its high conductivity when it’s completely
dry. The wires didn’t work well because it kept popping
out the circuit path and the conductivity was unstable. The
circuit line thickness was 2 mm.
Mycelium as Enclosure for Electronics
. We created en-
closures for DIY electronics such as microcontrollers, which
are commonly used in makerspaces or research labs (arduino
UNO, micro bit, and circuit playground). We 3D printed a
negative 3D model to be used as a mold for the arduino UNO
(Fig.1c), (Fig.5). As part of the exploration, other mold shapes
were used in order to have homogeneous pieces of 15mm
(0.5inch) thickness, the ones we used to make our electronic
circuits tests.
Mycelium as an electronic component
. We made a
breadboard out of mycelium material. This electronic com-
ponent size is 76mm.x51mm. (3"x2") and it allowed us to
replace the common plastic breadboard by a compostable
one. The bio breadboard was successfully developed and
we incorporated a connection in the circuit for a battery
Figure 4: Laser cutting and CNC machining tests in the
mycelium-composite material for tracing circuits.
Figure 5: Microbit and Arduino Uno enclosure.
holder and a potentiometer to oer interaction to the user
(Fig.1d). The bio-breadboard was laser cut and some etching
was made on both sides of it for design purposes (Fig.6a, 6b).
Finally, wires were used on the back of the bio-breadboard
following the designed circuit to enable conductivity on it.
For testing, we added some LEDs to interact with them by
making a composition (Fig.6c). We also made a comparison
between how a circuit looks like in a common breadboard
and in our proposed bio-breadboard (Fig. 7).
4 DISCUSSION
The use of biomaterials provide many advantages to product
design eld because they are made from natural renewable
resources, can be recycled, reused, or composted. Thus, they
are an excellent alternative to waste (failures and unused pro-
totypes) that now can be 100% biodegradable. We decided to
use mycelium because of its suitable properties for DIY elec-
tronics applications (heat resistant, thermal resistant, light
weight, degree of strength, shapeable and hydrophobic). Fur-
thermore, this biomaterial decomposes in nature in less than
90 days as any other organic waste. Common prototyping
materials such as PLA, acrylic, or FDM can remain in the

UbiComp/ISWC ’19 Adjunct, September 9–13, 2019, London, United Kingdom Lazaro and Vega
Figure 6: Biocompostable breadboard, making process.
Figure 7: Circuit in a Plastic breadboard vs. Bio-breadboard.
landll for hundreds of years as any other piece of plastic if
they are not disposed under the right conditions [9].
Even though mycelium-composite shows an alternative to
plastic in prototypes, it still has limitations in strength and
further physical test should be made to become a long-lasting
material. However, it is a great alternative material to use in
the iteration process of product design such as enclosures for
electronics, or chassis for embedding motors or any others
electronic components.
5 CONCLUSION
Prototyping materials are mainly based of plastic such as
acrylic or they contain a toxic resin in its composition such
as FDM. Using mycelium as a bio-composite material for DIY
electronics opens novel possibilities for replacing those non-
ecofriendly materials and making our practice, as researchers,
designers, makers or hobbyists, more sustainable. We envi-
sion its application to biodegrade enclosures and reuse the
electronic components in future projects, biodegrade failures
in the digital fabrication process and biodegrade material
that remains and is not used after laser cutting. This project
presented our process for growing our own biodegradable
material in dierent scenarios: to make buttons for switches
or keyboards, to create enclosures for electronics, to pro-
totype in bio-breadboards instead of plastic ones, and to
engrave and embed electronics. Future work will explore
other biodegradable materials to replace other plastic-based
and conductive materials, to conduct physical tests such as
tensile, strength, biodegradation time, heat resistance and
compostability.
REFERENCES
[1]
R. Abhijith, Anagha Ashok, and C.R. Rejeesh. 2018. Sustainable pack-
aging applications from mycelium to substitute polystyrene: a re-
view. Materials Today: Proceedings 5, 1, Part 2 (2018), 2139 – 2145.
https://doi.org/10.1016/j.matpr.2017.09.211 Second International Con-
ference on Materials Science (ICMS2017) during 16-18 February, 2017.
[2]
Natalie Alima. 2013. Mycotecture - growing into form - IAAC
Blog. http://www.iaacblog.com/programs/mycotecture-growing-
into-form- 2
[3]
Freek V.W. Appels, Serena Camere, Maurizio Montalti, Elvin Karana,
Kaspar M.B. Jansen, Jan Dijksterhuis, Pauline Krijgsheld, and Han A.B.
Wűsten. 2019. Fabrication factors inuencing mechanical, moisture-
and water-related properties of mycelium-based composites. Materials
& Design 161 (Jan 2019), 64–71. https://doi.org/10.1016/j.matdes.2018.
11.027
[4] DIYbio. 2008. DIYbio. https://diybio.org/
[5]
EcovativeDesign. 2010. The Mycelium Biofabrication Platform. https:
//ecovativedesign.com/
[6]
Kate Till Caroline. Franklin. 2019. Radical Matter: rethinking materials
for a sustainable future. Thames & Hudson.
[7] GROW.bio. 2016. Grow Bio. https://grow.bio/
[8]
Mitchell Jones, Tien Huynh, Chaitali Dekiwadia, Fugen Daver, and
Sabu John. 2017. Mycelium Composites: A Review of Engineering
Characteristics and Growth Kinetics. Journal of Bionanoscience 11, 4
(Aug 2017), 241–257. https://doi.org/10.1166/jbns.2017.1440
[9]
F.-D. Kopinke, M. Remmler, K. Mackenzie, M. Műder, and O. Wach-
sen. 1996. Thermal decomposition of biodegradable polyesters-II.
Poly(lactic acid). Polymer Degradation and Stability 53, 3 (1996), 329 –
342. https://doi.org/10.1016/0141-3910(96)00102- 4
[10]
Gavin McIntyre, Eben Bayer, and Amanda Palazzolo. 2018. Method of
growing mycological biomaterials.
[11]
David Mellis, Sean Follmer, Björn Hartmann, Leah Buechley, and
Mark D. Gross. 2013. FAB at CHI: Digital Fabrication Tools, Design,
and Community. In CHI ’13 Extended Abstracts on Human Factors in
Computing Systems (CHI EA ’13). ACM, New York, NY, USA, 3307–3310.
https://doi.org/10.1145/2468356.2479673
[12]
MOGU. 2017. Mycelium materials and technologies - from Waste to
Value. https://www.mogu.bio/
[13] MycoWorks. 2013. MycoWorks. https://www.mycoworks.com/
[14]
NaturalNews. 2018. Researchers develop blend of bio-
plastics that can decompose under diverse conditions.
https://www.naturalnews.com/2018-11-13- bioplastics-that-can-
decompose-under- diverse-conditions.html#
[15] NEFFA. 2016. MycoTEX |. https://nea.nl/mycotex/
[16]
Pat Pataranutaporn, Todd Ingalls, and Ed Finn. 2018. Biological HCI: To-
wards Integrative Interfaces Between People, Computer, and Biological
Materials. In Extended Abstracts of the 2018 CHI Conference on Human
Factors in Computing Systems (CHI EA ’18). ACM, New York, NY, USA,
Article LBW579, 6 pages. https://doi.org/10.1145/3170427.3188662
[17]
Raghunatha R. L. Reddy, V. Sanjeevani Reddy, and Gautam A. Gupta.
2013. Study of Bioplastics As Green & Sustainable Alternative to
Plastics.