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Biosensing for Human Computer Interactions

After the analysis of “Visualizing techniques with plants”, we will explore interactions for human computer interaction (HCI) through plants. The objectives of this research are revealing technical approaches and which kind of interaction can be performed.

Interactions between humans and computer is usually implemented by sensors. In 2009 Dan Saffer defined a sensor for human computer interaction like this:


A sensor is typically an electrical or electronic component whose job is to detect changes in the environment [Saffer2009, page 13].


We are surrounded by plants and plants are able to sense changes in our environment. The increasing problem with our environment forces us to reconsider our usage of technology. Hybrid solutions between natural resources and our current technology is able to decrease our current environmental issues [ICC2007, pages 15-21]. For this reason, it is obvious to explore the plant abilities of sensing for HCI. The sensor belongs to the basic components of any gestural system, which is used in HCI applications [Saffer2009, page 13]. In our context we replace the common electronic sensor with a plant. An additional electronic circuit translates these bio signals into electronic computer-readable signals. Accordingly to this approach, the gestural system is completed again.


The biosensing method is basend on the concept “Basic components of Gestural Interfaces” by Dan Saffer [Saffer2009, page 13].

The biosensing method is basend on the concept “Basic components of Gestural Interfaces” by Dan Saffer [Saffer2009, page 13].

The most used sensors in interactive systems detect pressure, light, proximity, acoustic, tilt, motion, and orientation [Saffer2009, page 13]. In this research we will figure out which of these detections a plant performs and how it is technically implemented. The introduced technology ranges from simple electronic circuits to complex systems. The presented solutions are ordered by its simplicity to complexity.


The resistor approach

A plant as a resistor between human and computer is an often used technique. The most art projects measure how conductive a plant is and react on this data. In many cases this approach is used for experimental sound performances, like “Plantas Parlantes” (2010) by Ricardo O’Nascimento, Gilberto Esparza, Javier Busturia, Jigni Wang, “Baumarktmusik” (2011) by MSHR, “Kraft Test Drummie and Robert Plant” (2012) by Cristian Martínez as well as the “Mosszillator”  (2012) [LandKuni2013, pages 34, 142-159]. It can be implemented easily through an Arduino and 1mOhm Resistor. This technique can detect touches and delivers information about pressure. Furthermore, the resistor approach enables interaction between the plant and other conductive objects. For instance, it can be used in projects with plants directly like the work “Genesis of Biosynthia II” (2011) by Benjamin Kolaitis or with fruits and vegetables (i.e. “Noisy Cauliflower”, 2013, by Cara Stewart or “Teardrop”, 2013, by J. Viewz). The resistor method is very often used for musical interfaces, which is related to its characteristics of a simple electronic signal and an easy implementation.



 The piezo approach

Another simple method of biosensing is the use of a contact microphone (piezoelectronic sensor). The contact microphone can detect vibrations on solid objects. This is useful for interactions on the plant branches (e.g. "Mogees", 2012) or thorns (e.g. “From the hills” and “Frishasin pijamas” by Cristian Martínez during 2013). The interactions are mostly connected with motion detection on the plant’s surface. This can be a tap, knock, or swipe gesture. The researchers of the project “Mogees” implemented an extensive gesture recognition system, which can be also adapted for HCI applications. Moreover, the same procedure can be used for environmental sensors as well. Especially, conditions like wind, growth or other vibrating interactions are easily detected, like the the installation “Tree Listening” (2012) by Alex Metcalf [AnHuMi2012, page 135] does. Environmental sensing is a key part of ubiquitous computing applications and therefore the piezo sensors are useful tools in this scope.


The capacitive sensing approach

Capacitive sensing is one of the classical technologies for human interfaces (e.g. multitouch screens). It avails from the human body capacitance, which enables us to measure the touch, proximity, humidity, and acceleration. The simplest approach of capacitive sensing through plants can measure the amount of touch and proximity. Many spatial sound installation, like “Akousmaflore” (2007) by Scenocosme [ISEA2011], “Baumarktmusik” (2011) by MSHR and “The Plant Ochestra” (2013) by Alexandra Duvekot, utilize this capacitive sensing method for creating an interaction between humans and plants. Beyond that simple touch detection with plants even more complex interactions are feasible. The new developed advanced “Swept Frequency Capacitive Sensing” technology of the project “Botanicus Interacticus” (2012) is able to detect the location of touches on a plant. In addition to that, their gesture recognition algorithm detects a comprehensive collection of gestures [PoSchoLoSa2012]. These gestures can be performed on any part of the plant. The technology behind “Botanicus Interacticus” is called “Touché” [SaPoHa2012] and was developed by Ivan Poupyrev and Chris Harrison. They measure a predefined range of frequencies from a plant, and then their gesture recognition software determines, if the performed gesture is correct or not. Fortunately, some DIY Hackers rebuild the system with Arduino (tutorial). Though the Arduino results are not as accurate as the “Touché” ones - it does not have such wide frequency range - it provides a technical access  for a broader audience.


The electric field measurement approach

The touch interaction between plants and humans with an electric field measurement is very often mixed up with capacitive sensing technology. From an interaction design point of view the differences are not so obvious, but the electric field analysis provides more accurate sensor values for a proximity measurement. Christa Sommerer and Laurent Mignonneau were the first persons, who used a plant as a human computer interface [SoMig1993]. Their installation “Interactive Plant Growing” (1992) measures the electrical potential difference (voltage) between the user’s body and the plant. Their interface is able to detect five different distance levels, which results in a lower or higher voltage value of the sensor [ICC2007, pages 86-87]. Depending on the user interaction the growth process of the artificial plants can be influenced. Another advantage of their approach is the location of the sensor. The sensor is hidden from the users view and is connected to the plant’s roots. The branches and leaves take over  the role of the antenna.


The biopotential measurement with electrodes

Electrodes are very well-researched circuits in electronic engineering. They used for measuring bioelectronic changes and are an important tool for medical treatments (e.g. EEG, ECG). In that relation, electrodes are utilized for Human Plant Interfaces. In an interactive art context, first explorations of electrical changes within a plant were explored by Yuji Dogane in his artwork “Plantron” (1992) [ICC2007, page 18] and by Christa Sommerer and Laurent Mignonneau in their installation “Anthroposcope” (1993) [GerWeib1993, pages 398-400]. Yuji Dogane utilized the generated signal from the plant and converted it to digital data (MIDI). His soundscape addresses the ecological understanding how humans influence and change their environment. In contrast to an audio feedback, the installation “Anthroposcope” combines the signal from the plant with the human heart rate and produces a computer generated animation [StSoMi2009].

At this time interactive artworks dealt more frequently with the plant signals as additional parameter for their artpiece then as an interface between humans and plants. For instance, the “Yucca Invest Trading Plant” (1999) installation by Ola Pehrson applied the method of Electroencephalography (Brain Computer Interface) to gather plants signals, which were translated to trading activities for stock exchange simulator. Later, the musician and artist Miya Masaoka used the same technique for direct interaction with a plant. Her interactive sound installation performance “Pieces for Plants” (2002) detects touches and proximity of persons. The sound changes according to the human interaction. The proximity interaction is not very accurate but good enough for detecting the presence of humans. Very similar to her approach the research project “I/O Plant” (2007) by Satoshi Kuribayashi, Yusuke Sakamoto, and Hiroya Tanaka is also able to detect biopotential signals [KuSaTa2007]. Their research results revealed that the measured signal depends strongly on the present environmental conditions. In that relation, the biopotential signal for touch or other signals are very different. A calibration method has to be implemented.

In spite of that, the artist Ivan Henriques explored the plant signals during his research for his artwork “Jurema Action Plant” (2011) in more detail. His research focused on action potential mechanism of touch sensitive plants like the venus flytrap or the mimosa pudica. The touch signals are recognized by a special action potential device that measures the action potential changes inside a plant cell. Unfortunately, the plant signal is very weak and it needs a strong amplifier to translate the touch signal to a computer. Additionally, only a few plants can send such a strong touch signal. How and when the signal is dispatched, depends on the species. The venus flytrap and the mimosa pudica are appropriate for the action potential approach, because they react immediately on a touch stimuli and dispatch a very powerful signal that is strong enough to be distinguished from other signals. For HCI application both plants are very useful, because they provide a visual user feedback after the touch. One circumstance has to be considered before touch sensitive plants can be used for a Human Plant Interface. The plant’s touch reaction is an exhausting task for the plant, and should not be frequently touched. Touch interaction can harm the plant and increases the possibility that the plant dies.

The last remarkable activities in the field of biopotential signals with plants in an art context were done by Leslie Garcia. Her plant-based biosensing kit “Pulsu(m) Plantae” (2012-2013) is able to detect environmental changes light and sound as well as human touch interactions. Fortunately, she documented the electronic circuits and the software development very well. For this reason, her biosensing approach with electrodes is very transparent and accessible for a wide range of artists and tinkerers.



The results

Biosensing with plants covers the common sensors touch, sensitive touch, touch location, pressure, motion (for gestural interactions), proximity, sound and light for HCI. Regrettably, the signal quality differs from plant to plant and has to be calibrated for each plant. Furthermore, the data of the biosensors will not be as accurate as the measurements of their electronic counterpart. Too many factors (plant growth, plant health, moisture, etc.) have a negative influence on an exact sensor value [KuSaTa2007]. In consequence of the diversity in signal quality and the lack of an exact evaluation, plants are suited perfectly as a tool for artistical interpretations. Media artists have already integrated this uncertain aspect in their experimental music performances. In spite of inaccurate data, plants are still reliable bio sensors for simple touch, tap, knock, and swipe interactions. Biosensing with plants reaches its full potential in context of spatial interaction. People are able to interact with their usual environment, and the technology behind these interactions stay invisible for the them. In this relation, biosensing with plants is a very suitable tool for ambient intelligence and ubiquitous computing applications. Especially, the research results of Alexander G. Volkov and his team look very promising for a better understanding of plant signals in an environmental sensor context [VolRufRa2006, VolAdJo2007].

Beyond the application of biosensing in interaction design, in our culture always exists ethical concerns related to biosensing. Especially, biosensing with plants prompt frequently the question about plant consciousness and plant soul (e.g. artworks “Pieces for Plants”, “Jurema Action Plant”). Unfortunately, the movie and the book “The Secret Life of Plants” put this scientific topic in a pseudo-scientific and esoteric context [Koechlin2008, page 137]. For this reason, current scientists are very careful in making statements about plants perception. The consequences in ethics and treatment of plants can be huge. This topic gets more interesting if we connect plant perception with locomotion. However, during my research I figured out that most of the above listed approaches are not real plant signals. For example, the technology behind “Botanicus Interacticus” and “Mogees” works on living and dead objects, too. The plant takes over the role as transducer. Except, the biopotential approach with electrodes comes close a to real plant signal. If these biopotential signals are equivalent to a perception, like human and animals do. It is not clarified yet [Koechlin2008, page 46]. Biologists [Koechlin2008, pp. 49, pp. 55] and philosophers [Ingensiep2001] are discussing this complex topic controversially and even emotionall.



[SoMig1993] Sommerer, Christa; Mignonneau, Laurent (1993). Interactive Plant Growing. In Visual Proceedings of the Siggraph ’93 Conference, ACM Siggraph, 1993; pp.164-165.

[GerWeib1993] Gerbel, Karl; Weibel,Peter (1993). Genetische Kunst - künstliches Leben (Ars Electronica Festival 93). PVS-Verleger, 1993.

[VolRufRa2006] Volkov, Alexander G.; Rufus , Don; A. Ranatunga (2006). Plants as Environmental Biosensors. In Plant Signal Behav. 2006 May-Jun; 1(3): 105–115.

[VolAdJo2007] Volkov, Alexander G.; Adesina, Tejumade; Jovanov, Emil (2007). Closing of Venus Flytrap by Electrical Stimulation of Motor Cells. In Plant Signal Behav. 2007 May-Jun; 2(3): 139–145.

[ICC2007] NTT InterCommunication Center (2007). Silent Dialogue. ICC, 2007.

[KuSaTa2007] Satoshi Kuribayashi, Yusuke Sakamoto, and Hiroya Tanaka (2007). I/O plant: a tool kit for designing augmented human-plant interactions. In CHI ‘07 Extended Abstracts on Human Factors in Computing Systems (CHI EA ‘07). ACM, New York, NY, USA, 2537-2542.

[Koechlin2008] Koechlin, Florianne (2008). PflanzenPalaver - Belauschte Geheimnisse der botanischen Welt, Lenos Verlag, 2008.

[Ingensiep2001] Ingensiep, Hans Werner (2001). Geschichte der Pflanzenseele - Philosophische und biologische Entwürfe von der Antike bis zur Gegenwart. Kröner, 2001.

[Saffer2009] Saffer, Dan (2009). Designing Gestural Interfaces. O’Reilly, 2009.

[StSoMi2009] Stocker, Sommerer, Mignonneau. Christa Sommerer & Laurent Mignonneau (2009.) Interactive Art Research. Springer Verlag, 2009.

[AnHuMi2012] Antonelli, Paola; Hunt, Jamer; Midal, Alexandra (2012). Talk to Me: Design and the Communication Between People and Objects. Museum of Modern Art, 2012.

[SaPoHa2012] Sato, M., Poupyrev, I, and Harrison, C. (2012). Touché: Enhancing Touch Interaction on Humans, Screens, Liquids, and Everyday Objects. In Proceedings of CHI’12. 2012. ACM.

[PoSchoLoSa2012] Poupyrev, I., Schoessler, O., Loh, J., Sato, M. (2012). “Botanicus Interacticus: Interactive Plant Technology” SIGGRAPH 2012 Emerging Technology Exhibition.

[LandKuni2013] Kuni, Verena; Landwehr, Dominik (2013). Home Made Bio Electronics Arts. Christoph Merian - Migros Kulturprozent, 2013


  1. admin
    June 14th, 2014 at 12:29 | #1

    The water transport of some plant body parts causes some accoustic signals.The Plant Orchestra (2009) project was built by Luke Jerram and the sound artist Matt Davies, which translates these audible signals to human perceivable audio signals. In relation to this plant sensoring method, the project Tree Listening” (2009-2015) project by Alex Metcalf is also an important one. The research about trees: Rendering Ecophysiological Processes Audible by the Zurich University of the Arts ZHdK explains the techniques in more detail.

    Another sound installation with plants is called Singing Plants & Plant Musicians (since 2010) and was developed by Jo SiMalaya Alcampo. In this project a capacitive sensing method was applied, which is described on the empyre Mailinglist:

    The plants are connected to sensors using conductive thread, it is very much like spider webs. The thread is wired to a circuit board installed with capacitive touch sensors. The board is connected to a microcontroller. Software is used to assign audio and video responses. – Jo SiMalaya Alcampo

  2. June 22nd, 2014 at 13:44 | #2

    The talk Bio-inspiration for adaptive design solution by George Jeronimidis has some interesting points related to biosensing with plants in an architectural context, especially the part about passive and active responsive integrated sensing (starts at 47:10min) sounds very promising. Furthermore, I hope the talk Designing with living systems, a new prerogative? by Carole Collet is uploaded soon.

  3. admin
    September 26th, 2014 at 10:12 | #3

    Michael Lucenkiw wrote a nice master thesis “Flora Machina: A Defensible Cyborg Landscape” (2014) about biosensing in the domain of landscape architecture. His exploration of cyborg plants provides some nice thoughts and ideas for an ongoing research in Human Plant Interactions.

    The abstract of his thesis:

    The landscape is under constant threat from human kind and cannot evolve fast enough to protect itself adequately. By augmenting an ecosystem’s natural resilience with cybernetic technology, it will be better equipped to ensure its survival in an urban setting. This practicum will investigate the creation of a cybernetically-enhanced ecosystem, the cyborg landscape, and how this organism(s) will know and understand the world around it. This practicum has been inspired by the idea of the cyborg, research on plant intelligence, installations, artistic interventions and ideas of chance and performance introduced by composer John Cage. The cyborg plant is a strategy used to expand on the limitations of a plant allowing adaptation to situations and environments. To become a cyborg, is to have an intimate bond between technology and organism, both functioning as one to overcome limitations limiting survival in the environment.

    His thesis contains also very interesting references. For instance

    – The sound installation “Invisible Forest” (2013) by Augustine Leudar using electrodes for sensing plants in an art context.

    – The Public Lab Community and their great projects, like Infragram for analyzing plant health.

    – The EU-funded project PLEASED – PLants Employed As SEnsing Devices seems very ambitious for understanding plant based signals. For sure the results will be also useful in artistic context.

  4. admin
    October 5th, 2014 at 00:03 | #4

    The wiki centre ressources labomedia about biofeedback has also a nice link to an instructable tutorial, which explains the usage of touché (capacitive frequency sensing) in relation to a plant.

    Singing plant. Make your plant sing with Arduino, touche and a gameduino

  5. admin
    February 17th, 2015 at 15:04 | #5

    Another sound/music installation Beet Box (2012) with plants that uses the capacitive sensing approach is created by Scott Garner.

  6. admin
    March 2nd, 2015 at 09:38 | #6

    Another sound installation called Biopilot v1 (2014) by Mirjana Batinic detects electromagnetic changes for manipulating sound. For this reason, I suggest electrodes are used detecting these changes. The artist describes this projects as:

    Biopilot 1.0 [Sound Modulation upon the Plant Model] is a cross-disciplinary tech-biogarden installation.
    Set as a controlled sound platform, this work is open for the audience to interact by playing with devices and making their own sounds with the living systems. The work tends to be live, pulsing, art-sci organism.

  7. March 23rd, 2015 at 21:56 | #7

    Martin Howse published on his website and on the FoAM wiki a comprehensive list of information about further plant sensing approaches (e.g. measuring the Galvanic Skin Response).

  8. May 11th, 2015 at 17:05 | #8

    The sound artist Mileece used plants as an instrument in her music performance Bio-Electricity (2013) at the MoMa New York (article). In her performances she applied the Galvaniv skin response as she has stated in the Vice Motherboard documentation. On her tumblr blog your get more information about her activities related to sound art and plants.

  9. June 9th, 2015 at 17:43 | #9

    Jasmeen Bains, Tyler Bradt, and Yi Zhou created the sound installation The Language of Plants (2015), which was presented at the Grow Op 2015: Culture and Landscape exhibition in eGladstone Hotel in Toronto. They used a similiar approach of making Ecophysiological Processes Audible that is similiar to the installation Tree Listening by Alex Metcalf and the research by the Zurich University of the Arts ZHdK.

  10. July 6th, 2015 at 16:28 | #10

    The scientist Amay J. Bandodkar, Wenzhao Jia, Julian Ramírez and Joseph Wang working on pen-like technology for drawing bio-sensors on organic materials. Their goal is to develop bio-inks, which can serve as electrodes. This method is also in relation to biosensing with plants an very interesting technology. I am curious how the research will continue. Here is the link to their publication:

    Bandodkar, A. J., Jia, W., Ramírez, J. and Wang, J. (2015), Biocompatible Enzymatic Roller Pens for Direct Writing of Biocatalytic Materials: “Do-it-Yourself” Electrochemical Biosensors. Advanced Healthcare Materials, 4: 1215–1224. doi: 10.1002/adhm.201400808

  11. admin
    September 11th, 2015 at 15:09 | #11

    Lately, this summer Mélodie Fenez performed a Plant music concert a.melodie (2014-2015) during the Bio-sonfication event at Spektrum in Berlin. In the beginning of her performance she told her installations is based on the circuit by Karl Heinz Jeron. For this reason I guess the Biosensing works with measuring electronic magnetic fields. I am not 100% sure, because some pictures look like a variable resistor method. However, even the Vice magazine article gives more hints to the electro magnetic field sensoring method.

  12. admin
    September 11th, 2015 at 15:21 | #12

    Another sound installation called Audible Garden (2015) by Amanda White explores the interaction with domestic plants. The sensors and the descriptions seems like a electrode sensing method, which was also used in the performance Pieces for Plants by Miya Masaoka.

  13. September 13th, 2015 at 22:35 | #13

    Above int the text, I have introduced the artist duo scenocosme and their installation Akousmaflora. This installation was not their only one. The Installations Phonofolium (2011) | PDF, Phonofolia (2012) and Lumifolia (2013) apply also an electrostatic (capacitive) sensing approach with plants.

    In 2013 they even applied the electrostatic sensing method to wood. Their sound installation Matières sensibles (Sensitive matters), 2013, is able to measure and transmit the human electrostatic voltage and transmits it to a microcontroller with a sound system. Wood is also an crucial applied material in their installation Ecorces (2012), which deals with absorbed human heat on the wood.

  14. February 2nd, 2016 at 16:41 | #14

    Most of the installations were developed in the 21st century, I think the oldest one mentioned is from Sommerer and Mignonneau 1993. I was wondering if there were also installations before the 90s? Is the increase of newer installations due to a new awareness of plants? Or if there may have been older installations, maybe they are not as much documented as todays?

  15. admin
    February 3rd, 2016 at 03:28 | #15

    Hi Till,
    During the 60/70ies people (researchers on bonatic and sound designer) experiment a lot with plants. It was on the way to become a real serious science topic until pseudo researchers tranformed it to an esoteric topic. Like the book and movie “Secret Life of Plants” and the Japanese research couple with cactus.

    This page has a nice interview about the Bio Sensing Art in the 1970s or check my presentation slides. Since several years it seems the topic plant sensing has a comeback. The art scene took over the topic, because of the greenwave and sustainable product lifecyle. Another reason might be that reasearchers have really emotionally discussions about it. Many have different opinions, that have influences in ethics and philosophy. Some nowadays installtion use exactly the same sensing approach from the 1960s. Some other a real new, like enhanced capacitive sensing methods.

    If you want to know more about the topic please read the introduction of my master thesis or check these pages.

    I hope that helps.

    Viele Grüße

  16. admin
    February 15th, 2016 at 04:58 | #16

    Johannes Marschall, Till Fastnacht, and Abraham Ornelas Aispuro have built up a public Human Plant Interaction installation in Jena, which is called Sonnengarten (2016). Based on their documentation I assume, they applied the Swept Frequency Capacitive Sensing method for detecting touch gestures.

  17. Till
    March 26th, 2016 at 00:35 | #17

    We considered using SFCS, but in the end we used the MPR121sensor in a breakout version from Adafruit because the advanced touch detection was not necessary.

    Btw: Thank you very much for your work and the publications about it!


  18. June 15th, 2016 at 15:31 | #18

    Some weeks ago, Esteban de la Torre and Judit Eszter Kárpáti form EJTECH exhibited some plant based sound installation at CHB – Collegium Hungaricum Berlin. In that exhibition The new ways of viscosity they used mostly the biosensing approach with electrodes.

    Furthermore on their vimeo channel they posted some more experiments with plants – which I have to guess – seem to use capacitive sensing for detecting the human interactions.

  19. Mike
    July 16th, 2016 at 14:10 | #19

    Im surprised you missed this out – its probably the most advanced attempt at this kind of work in the field also by Augustine Leudar (mentioned above) :


    Hes doing a PhD in plant electrophysiology and art combinations

  20. Mike
    July 16th, 2016 at 14:11 | #20

    He also has a text “Integrating plant electrophysiology and art” here :


  21. Mike
    July 16th, 2016 at 14:17 | #21

    Also you should note that exactly the same results of changing a plants “capacitance” can be achieved with a piece of damp cloth – it is complete fraud and tells us nothing about what a plant is “perceiving”.

  22. admin
    July 16th, 2016 at 21:25 | #22

    Hi @Mike ,

    thank you very much for your comments and links! Unfortunately, during my master thesis writing I have not stumbled on Augustine Leudar before. Later, I found his work and added some links about his art installation and research on my comment of this blog post (more above) from September 26th, 2014. His text “Integrating plant electrophysiology and art” I have not known yet, very nice to have something new to read. Thanks a lot for this link!

    Regarding the perceiving plant signal, I agree with you. In my conclusion of this chapter, I wrote that measuring the “capacitance” is not a real plant signal. The plant is more or less used as a sensor body. Measuring real plant signals is not a trivial activity, which Ivan Henriques revealed on his research website https://ivanhenriques.com/re-search/naturetechnology/

    There exist a lot of noise (and other electromagnetic fields and signals), which disturbs the real plant signal measurement. The equipment for those tests is pretty advanced and expensive. It is almost impossible to apply those technology to an artwork. For that reason, I presented also the other approaches of simulating a plant signal/plant interaction. In the end, I think it makes the topic more accessible for everyone.

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