The Petri Dish – Instructables

Making  “The Petri Dish …”


Table of Contents

Flower making

Making the installation


General materials list:

  • Servo motor, at least MG955 or equivalent
  • 0.96″ OLED display, I2C interface (you can use a bigger one too)
  • Two sets of 5v power supply adapter and 5v breadboard power module
  • Assortment of jumper wires or 28AWG wires
  • Thin gauge wire, ~10m
  • Thick gauge wire, ~2m
  • Tools; pliers, snips, wire strippers, power drill, 2 spanners
  • Wood glue
  • Scraps of plywood
  • 2×1″ wood planks, single 10ft piece will suffice
  • some clamps of various sizes
  • multimeter
  • M3 screws, M8 bolts

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1. Making petals

1. Making a petal

  1. Create drawing plan for how many petals to be included in flower
  2. Get tools in order; snips, wire cutters, pliers, ruler
  3. Cut wires to length, about 60cm in our case. I am twisting a pair to create an interesting pattern as well as to make the wire thicker
  4. Use rounded pliers to twist
  5. Shape a petal using the drawing as a guide
  6. End off with a loop in the middle to allow for connecting a linkage later
  7. Flatten the tip of the petal
  8. Apply curvature to the shape
  9. A petal is done! Repeat till you are done (5 times in our case)

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2. Attaching petals

2. Attaching the petals

  1. Use a thicker gauge wire to create a 6-sided polygon.
  2. Strip off a small section of the thin wire (~8cm)
  3. Coil on both ends to connect a petal to the polygon
  4. Repeat till all petals are connected! Make sure all petals can swivel back and forth freely

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3. Petals’ Base

3. Making base for petals

  1. Cut out a section of thicker gauge wire (~9.5cm)
  2. Twist on both ends, facing in different directions
  3. Connect one to each corner of the 6-sided polygon
  4. Twist an additional strand into one of a lollipop shape; this will act as the connector to the stationary plastic tube that supports the moving main metal linkage.
  5. Connect 2 linkages first, check if they are holding the petals equally. For my first try, it wasn’t(see picture with red circle). Adjust by making one of the linkages shorter.
  6. When fixed, continue with the rest of the linkages.
  7. With all the linkages connected to the stem base, you can twist the bottom of the wire around the plastic tube.
  8. Let’s begin making the final part of the flower!

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4. Flower mechanics

4. Linkages for petal mechanism

  1. Twist another strand in the similar lollipop shape. This piece goes all the way through the plastic tube to the bottom. (~35cm, depending how long you make the stem..)
  2. Create a linkage that is slightly different. One of the ends is at a 45 degree to the other. You will need 6 of these as well.
  3. Connect one end to the loop in the middle of the petal. The other goes to the ‘lollipop’ wire made in step 1 of this section.
  4. Again, some of the linkages might be longer than others. Adjust accordingly till all six are connected equally to the middle .
  5. When you are done, you can test it out by pushing and pulling gently at the other end of the rod made in step 1. (See video below)

The Flower is done!

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Making the Installation

1. Prepping the materials

1. Materials Prep

Plywood(1.2cm or thicker)

  • 4pc: 20x11cm (housing sides, A)
  • 2pc: 15x15cm (housing lids, B)
  • 1pc: 20x25cm (console surface, C)

2 x 1 inch planks(pictured darker colored here)

  • 1pc: 20cm (center connector, right notch on both sides: 2.5cm depth, half width, D)
  • 1pc: 30cm (middle connector, left-right notch, E)
  • 1pc: 7cm (console surface connector, left notch, angled cut at other end, 60-degrees, F)
  1. Cut to dimensions the above.
  2. Use a compass to draw a circle to act as a guide to cut out rounded ends.
  3. Drill 8mm holes or whatever size bolts that you are using to link the connectors together.

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2. Electronics box

2. Making the electronics box

  1. Attach the center connector(D) to one of the housing lids(B). You can use M3, 25mm screws.
  2. Drill a hole that is big enough for the plastic tube through the middle of the center connector(D) and the housing lid(B). An additional hole is drilled for some wires for  electronics.
  3. Connect two pieces of housing sides(A) with a small hinge. You can use M3, 10mm screws. Do the same for the remaining two pieces(A).
  4. Place the two sets of the connected housings at right angles to each other to form a 4-sided box.
  5. Align the top housing lid to this housing and drill a screw through to connect them.
  6. Take note to only connect one of each of the two sets of housing sides(A), so that we are still able to open the box on two sides. (see picture for a view from the underside)
  7. Attach the bottom housing lid(B) as well, with screws.
  8. Short sticky foams are placed to limit how much the housing sides can be pushed in.
  9. A hole is drilled on the attached side of the housing for wires.

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3. The console

3. Making the console

Plywood(~1.8cm thickness)

  • 2pc: 7 x 8cm (cuboid sides, G)
  • 1pc: 5 x 8cm (cuboid side, H)
  • 1pc: 13 x 8cm (cuboid base, I)
  • 3pc: 5 x 8cm (jar sides, J)
  • 1pc: 8 x 8cm (jar base, K)
  1. Cut to dimensions using the above specifications; these are for making slots for holding a cuboid and a small glass jar.
  2. Draw a 4x3cm rectangle and a circle of 4.6cm diameter on the console surface(C), then cut them out.
  3. Drill four equally spaced holes in the middle connector(E); these are for LEDs
  4. For the cuboid container, use 2 pieces of (G) and 1 piece of (H) as sides, and 1 piece of (I) as base, and glue them together, you can use wood glue like Titebond.
  5. For the glass jar, use 4 pieces of (J) and 1 piece of (K) and glue them up as well. See picture for reference.
  6. Glue console surface connector(F) to the top, middle part of console surface(C).

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4. Arduino + servo + linkages + breadboard

4. Install Arduino, servo and linkage and breadboard

Scrap Plywood

  • 5pc: 1.3 x 2.5 x1.6(thickness) cm (servo supports, L)
  • 1pc: 7 x 4 x 0.5(thickness) cm (servo base plate, M)
  1. Cut to dimensions using the above specifications; these are for making a housing to hold the servo in place.
  2. Drill 2 holes or more on the base plate(M) for screwing it to the enclosure. Make sure that you can still access these after the servo is installed.
  3. Glue two sets of two pieces of (L) together to form (L2)
  4. Align the servo and glue up a piece of (L2) to the base plate on one end, to allow for the servo to be attached via m3 screws.
  5. Then glue a piece of (L) at an angle, and glue a piece of (L2) lying flat on top of it. See picture for reference. Make sure that you glue these two pieces in a way that allows you to remove the servo later. Then screw the servo onto this support with M3 screws as well.
  6. Install plate with servo onto enclosure. You can temporarily remove one of the screws from the top and bottom of one side of the enclosure, and swing open the side to have more access to the inside of the enclosure.
  7. Create a linkage as shown to connect it from the servo to the bottom of the metal linkage of the flower.
  8. Install Arduino onto one of the swinging side panels with M3, 10mm screws. Attach breadboards with double sided tape as desired on the inside. Here you can see I have attached a short one inside, and another extra breadboard on the other swinging side panel.

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5. OLED + magnifier

5. OLED + Magnifier

Plywood(5mm thickness)

  • 2pc: 11.6 x 2cm (glue up these 2 pieces together, the OLED will be attached to this, N)
  • 4pc: 5 x 3.2cm (side supports to hold m8 bolts, O)

Plywood strip(width: 1.1cm , height: 1cm)

  • 4pc: 8.4cm (housing’s top and bottom frames, P)
  • 1pc: 2cm (housing’s bottom spacer, Q)
  • 2pc: 7.2cm (housing’s side spacers, R)
  1. Cut to dimensions using the above specifications; these are for making a magnifier to increase the viewing size of the tiny 0.96″ OLED we are using.
  2. Glue up the pieces using the supplied CAD pictures as reference.
  3. Drill a M8-sized hole on each side of panel (O)
  4. Align with the glued up panels (N) and drill m8-sized holes.
  5. Attach the magnifier housing and OLED pieces with M8 bolts and nuts as shown.
  6. Attach hinge(0.5 x 1.5inch) at back, bottom of housing.
  7. Then attach this assembly to the center connector as shown.
  8. The OLED display is held in place with blu-tack, and wires can be tucked from behind as shown.

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6. Neopixels installation

6. Let’s install some Neopixels!

  1. Solder wires onto Neopixel(SK6812)
  2. For center connector(E), feed wires through holes and attach them together in series. Remember to follow the indicated direction on the underside of each Neopixel.
  3. Place a Neopixel a little above the center area of the petal as shown.
  4. Feed a Neopixel through hole in console area.
  5. Add another breadboard power supply module for powering the center connector and console’s Neopixels.
  6. The flower petal’s Neopixel will be powered together with the servo motor.

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7. Finishing touches

7. Finishing touches

1.5cm wide single-sided sponge tape

  • 2pc: 6.8cm (horizontal outer linings)
  • 2pc: 10.5cm (vertical outer linings)
  • 2pc: 3.2cm (horizontal inner linings)
  • 2pc: 3.8cm (vertical inner linings)
  • 1pc: 3.5cm (bottom lining for pipette)
  • 2pc: 11.5cm (side linings for pipette)
  • 2pc: 5cm (side linings for magnifier)
  • 1pc: 8cm (left vertical line for manual area)
  • 1pc: 14.5cm (horizontal line for manual area)
  • 1pc: 6cm (right vertical line for manual area)
  • 2pc: 20.7cm (side linings for central connector)
  • 3pc: 6cm (for wrapping flower stem)
  • 1pc: 16cm, cut to half of width (lining electrolyte area)

1pc: 10 x 60cm cloth

  1. Cut single-sided foam tape according to dimensions and stick them onto the console area.
  2. Use bubble wrap to insulate stem area. Then use aluminium foil to wrap it up. As we are going for an all-metal look for the flower, its a good choice.
  3. Then use wide masking tape to cover the neopixels as shown.
  4. We will next use bubble wrap to cover these areas, partly to act as a sort of diffuser for the LED lights. Do this for both the dripping area and the center connector as shown.
  5. The finished product with lights is shown above.
  6. Fix the black cloth around the console area, you can use your own methods. Here I used double-sided tape and some straps.
  7. Print the artwork(below) for an instruction manual and paste it at the manual area.

“Instruction manual”

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8. We are done !

Wiring Schematic

  1. Use M8 bolts to connect the 3 connectors(D, E, F)
  2. Wire up all the electronics using provided schematic(above).
  3. Load up the code to Arduino.
  4. Connect 5v power supplies to the two breadboard power supply modules.
  5. Cross your fingers and fire up the installation!

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9. Demo video

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The Petri Dish

Concept premise

At the dawn of the 21st century, the Internet’s birth enabled social media, unlimited 24/7 news on a global scale and free information about any topic imaginable. There’s also Youtube and a million other media sharing outlets in the digital sea of bits.

Information has become commonplace and democratised. But as we head further into the next few decades, how will information continue shaping our daily lives and influence how we carry out our daily tasks?

My project, affectionately named “The Petri Dish”, is a social commentary on how we have come to embrace information that is fed to us in an unquestioning manner. Will we use our intuition to understand and make wise choices, or will we lose our ability to perceive, succumb to our ‘technological overlords’ and follow their instructions blindly?

On a side note, it is named as such because we are used to thinking of performing experiments in a lab using a petri dish. Here I am presenting the notion of the participant at the installation as “The Petri Dish” instead.

Development of Idea

It all started out with the idea of highlighting social issues that are deeply relevant to the current century. My initial attempt was to bring to attention the problem of waste products, and how our insatiable consumerism habits will ultimately come round and bite us. It was a simple idea; there was to be a trash can that will project whatever goes in towards two artificial ‘local environments’, a terrarium and an aquarium. The terrarium represents our living environment, and the aquarium represents our water bodies, e.g. a lake. On further development, there were a few issues that prompted a pivot. Firstly, the scale and scope was too big and wide respectively, and I didn’t feel a certain intimacy was achieved as the object was not focused and directed.

“The Petri Dish” was thus born.

The participant will get to nurture a flower, guided by instructions from a screen. Initially, I was hoping to utilise the whole lineup of gardening stuff: soil, fertilisers and water. In the initial body-storm exercise, I was given feedback that it probably is a little too much, and doesn’t add to the fact that the flower is kinda ‘unreal’ in the first place, so mimicking ‘real gardening’ with all bells and whistles might not be the best approach. Thus, the setup was dramatically reduced to only one element, an ‘electrolyte’, and the participant will decide accordingly how he/she will approach the task on hand and achieve a ‘satisfactory’ result.

The screen will always give false instructions, so after a few rounds, the patient but eager participant will realise that he/she must use her own intuition to nurture the plant sufficiently and stop when its just right and ignore any contradicting instructions from the screen.

Ultimately, the installation is designed to frustrate participants and stimulate distrust of the screen.

Design Process

Inspiration for flower mechanics: Ever Blooming Mechanical Tulip by jiripraus

Initial Ideas

Overview of how it works

Dimensions, dimensions…

Interaction console details

See here for details on initial conceptualisation.

Further development after class feedback

Design refinement

As mentioned above, after two rounds of user feedback, I have refined the interaction to become much simpler. Now the user only controls the amount of electrolyte(water) he/she wants to apply. And information will be presented through the flower’s mechanics and the OLED screen.

Prototypes (Rough & Polished)  &  User Feedback

Rough Prototype

Rough Prototype

Feedback for rough prototype:

  • Replace soil with something representational(try not to use real soil..)
  • Participants feel obligated to not kill the flower
  • Signage with instructions is sometimes not considered to be important to look at
  • Indicators for current state of flower is crucial for participants to make ongoing decisions
  • Usage of perhaps colors to guide participants with indicators and ingredients to use

See here for more details on body-storming session..

Polished Prototype

Feedback for polished prototype:

  • What does the 53% represent? Seem like it doesn’t matter.
  • Is there supposed to be something else after the growth part? Lack of further instructions from screen.
  • Currently, participant is unclear if he/she is following the instruction closely (this is partly due to the fact that the code is not working properly).
  • Consider change 53% to 53ml, could work better as the dropper is measured in ml.
  • Servo motor creates alien-ish sound; visual and audio links to the character of being a alien
  • Use Optic fibre to create lights for flower
  • If flower is dying, the movement can be glitchy to signify ‘dying’ in the ‘alien’ sense
  • The fact that following instructions doesn’t work could perhaps somehow be more emphasised

The interaction of liquid versus flower bloom is somewhat effective. I feel that overall the code needs to work much better(it was only working 20% ..), and the OLED screen’s instructions has to work in tandem with the participant’s interaction.

Grand Finale !

Final improvements:

I added some lights on the console and center connector to suggest movement of the electrolyte. There is also a light on the flower to hint at its state. Overall the lights add to the installation’s visual mood when deployed in a dim area.

The code is working pretty much this time, and I have figured out the quirks associated with the OLED, that is perhaps for another post.

An instruction manual has been added to the console , but it is not merely aesthetic. There is some information regarding the flower that can help the player make informed choices.

Buzzer sounds have been added as well to help with providing feedback throughout the interaction process.

Lastly, part superficial part practical, the OLED has gained a magnifier in front of it to help players make out stuff on its tiny screen. It kind of adds a little character to the whole piece as well.

Make your own !

Instructables w/ code and schematics

In-class final presentation

Parting thoughts:

I could sense the urge in participants to “win” the game, I guess that’s the power of ‘gamification’. It is also interesting to see everyone’s different approaches, even though they were all pretty aware of the underlying premise of the installation. I think the refinements worked quite well too as I think theres less confusion about what is to be done, and the screen is much easier to be read this time.

The information on the manual is pretty crucial, and it was a pity it could be read easily with the lights off. Engaging the installation in a dark environment is definitely more desirable, and sets up the mood appropriately as well.

Speaking of moods, I think that’s an aspect that I can work on more. The establishing of surroundings can be better utilised, great examples include the ah gong photo frame and the space dome pieces.

Though thoroughly challenging, I had a great 13 weeks for this module and look forward to more in my upcoming years! cheers!

Final Project Development: Drawings

Installation overview


  • Load cells
  • Servo(s) / Steppers
  • OLED displays
  • LEDs
  • Hygro sensor (moisture sensor)
  • Capacitative sensors (DIY with aluminium foil), pending usage..


All measurements are most probably highly tentative, subject to materials availability and also subject to change after testing..

Flower and pot details

The mechanics of the flower is TBC as of now. References here:

Botanical Engineering from IDEO labs

Ever Blooming Mechanical Tulip by jiripraus

Participants’ console


How does your audience experience your project?

They will be allowed to do the following, in any order and times they please.

  • Add water
  • Add soil
  • Add fertilisers
  • Remove any of the above
  • Observe flower behaviour and react accordingly.
  • Retry if flower ‘died’

Is it for a single person to engage with your project or for multiple participants concurrently?

It is designed for two participants concurrently.

What is the interaction or situation you are creating for your audience?

The situation I am attempting to create is one of questioning ‘authority’. It is essentially an abstraction of what we are faced with on a daily basis.

Every day, whether at work or in school, we are constantly fed with instructions of all kinds; from people who know better or otherwise. It has come to a point where there is a serious lack of critical questioning.

Schools are increasingly promoting a more inquisitive approach to learning, especially at the tertiary levels.

In this interaction, I aim to re-create the dynamics of the aforementioned problem; participants are given a set of detailed instructions, to nurture a flower into full bloom. However, after repeated attempts, they will realise that even if they follow the instructions to the letter, they will inevitably fail.

The odd individual who chooses to take charge of his/her own destiny and tap into his/her skills of acute observation and reasoning, thereby acting accordingly will be duly rewarded.

What is the intention of this interaction?

The decision to have two participants is critical to the concept. The installation aims to critique prevailing societal norms to not question ‘authority’, especially when it concerns processes that one is not familiar with.


  • How to effectively carry out recycling at a grassroots level
  • How to verify water from the taps are safe for consumption
  • What is the logical stipulated number of hours we should spend at work and if all safety issues are adequately addressed

These examples might seem far-fetched, but in a mature, modern, first-rate society, these are serious issues that everyone needs to consider, not only for their own good but also for people they care about.

In an ideal situation, all these ‘issues’ are ‘well taken care of ‘. But the fallacy of this assumption arises whenever accidents happen and get reported in the news. That is almost always the case when major scandals get unveiled and millions of tax dollars squandered.

The modern society we live in comfortably abstracts many of these processes away for our ‘benefit’, so that we can focus on what we do best, to specialise and contribute economically; and to be in a constant chase for material consumerism and the quest for bigger and better things. I digress..

Final Project Development: Body Storming

Instruction sets


What did you learn from the process?

The extremely fast-paced process of making a paper prototype forces me to condense the essence of my concept to the bare minimum; the absolute essentials that is required for others to understand and interact with. This may feel overly limiting at first glance, but it allows the designer to test out his/her idea with only fifteen previous minutes of his/her life wasted!

Another critical lesson learnt was that having 2-3 variables for participants are more than enough for meaningful interaction. Initially I had the idea of including more variables; like a slowly-spinning platform that forces the participants to either move or use different items as time passed, and more kinds of soil and fertilisers to complicate matters.

Having two players introduces an interesting, albeit unpredictable element to the implementation of the concept, and it is something that I might need to test further with other players.

Rough transcript of received class feedback:

  • Replace soil with something representational(try not to use real soil..)
  • Participants feel obligated to not kill the flower
  • Signage with instructions is sometimes not considered to be important to look at
  • Indicators for current state of flower is crucial for participants to make ongoing decisions
  • Usage of perhaps colors to guide participants with indicators and ingredients to use

What surprised you while going through the process?

It is really surprising how much gaps the human mind can fill when it comes to looking at ‘representational’ motifs and immediately understanding what they each stand for.. For example, participants could tell that the crudely assembled object represents a flower by a satay stick with 5-6 pieces of square papers pierced at the top..

Also, from the direction the pieces of paper are facing; upwards or downwards, participants can imply whether they are improving or worsening the situation.

How can your apply what you have discovered to the designing of your installation?

I will first decide on how many elements participants can interact with; soil, water and fertiliser etc, as well as the form they will be taking on. The visual cues are going to be crucial to allow clear understanding of what is to be done, and how to go about doing it. This can be achieved with colors, and maybe letters and lights.

The concept definitely needs more refinement and simplification. Currently the interaction does not feel fundamentally sound; a clearer final goal and streamlined steps need to be devised.

Originally I have intended to split the process of interaction to different ‘stages’. But seeing the demo test convinced me that it would be more viable to just have a singular stage where users can do any number of things before the conclusion. Simple is better.

Yoko Ono’s Cut Piece

“Cut Piece” (’65) by Yoko Ono for “INSTRUCTIVE AUTO-DESTRUCTION” by Anthony Cox in “Art and Artists”, August, 1966

How does it change the viewer’s relationship to the work?

In “Cut Piece”, viewers were invited to participate and profoundly shape the final outcome of an ‘artwork’ in a very direct manner. The complexity and implications of the piece were radical and groundbreaking as the artist has dedicated her body as the subject. Traditionally, when a viewer interacts with a piece of work, the nature of the interaction reflects the viewer’s state of mind in terms of aesthetic, mood etc. However, in “Cut Piece”, the viewer’s interactions signified much more. It was a manifestation of his/her desires; the uninhibited nature of one’s self. In the collective form, the total effect of viewers’ actions portrayed a certain sense of the anarchy and primal, chaotic nature of the human psyche. Such an effect would be hard to achieve with an inanimate subject in the same rein. The fact that there are real tangible stakes(the well-being of another person) involved in the process and outcome of the piece, brings out other aspects like societal inhibitions and collective psychological behaviours of its participants. In essence, it’s a social, science and art experiment all at the same time; ‘speaking your mind’ in the utmost sense.


How does it alter the way an artist or designer create the work, when there is an interactive component?

The work becomes much more experiential for the viewer, and the outcomes are indefinitely varied with each iteration. The process takes center stage, and the result may or may not become inconsequential. There is a shared sense of deeper meaning being derived; shared because each participant’s actions influences the one that comes after, and deeper meaning as there are layered meanings accumulated as the work progresses. The artist cedes much control to chaos, and the typical process is turned on its head. Here, the artist decides the starting variables and allows the process to occur organically. There is no inkling of what might happen and what the end result resembles. Interestingly, a simple parable of such a mechanism in the real world would be a presidential election(subject). The candidates(variables) are shortlisted, and the people(participants) vote accordingly to their judgement(emotion/logic). The results(final outcome) can be pretty arbitrary and unexpected, yet it reflects the collective wisdom and perceptions of the society in question.


A derivative of this seminal piece was Marina Abramović’s Rhythm 0(1974). Here, Marina altered the variables, by placing 72 objects on a table for her participants to use. There were ‘positive’ and ‘negative’ objects, allowing her viewers to perform good or detrimental acts. The narrative here is further intensified, as the objects reminded the participants that they could either do good or evil. The emphasis on moral choices is central to the eventual outcome. It became potently clear that the reminder was inconsequential. Most people were inherently ‘savage’ by nature.


On a lighter note, interaction can be employed as a way of facilitating dialogue(verbal and otherwise) between artist, viewers and society. As such, the artist ‘designs’ the central idea and interactions as perimeters, and presents it as a live petri dish, after which, may decide to perform an interpretation on the outcome(s). The exploration happens on a participatory level, as opposed to the traditional singular point of view.