How to Construct Tool Kits

MANY DIGITAL TECHNOLOGIES occupy a curiously contrary position. On one hand, they seem to offer engagement and empowerment for individual users. On the other hand, they are often highly controlled and monopolized technologies that bind users into particular practices and relations. Such an observation has been made through numerous analyses of an array of digital gadgets, data, and platforms. Digital technologies organize devious relations to a seemingly empowered if minutely surveilled user, from social media that profiles users while enabling views to be broadcast to apps and wearables that track sleep and fitness for the promise of greater well-being and productivity. Digital technologies manage, inform, and otherwise mediate everyday activities, and these functions are overseen by a limited number of organizations with often questionable agendas.[1]

To unravel the typically rigid contours of digital devices, many technology advocates have begun to assemble microcontrollers and sensors and code to develop a more informed engagement with these machines. Here the tool kit becomes a way to fashion a more deliberate encounter with digital devices. By making electronics from the ground up, one is meant to be able to understand the decisions that are made in setting up technical configurations one way and not another. But even the fashioning of a tool kit already contains a set of built-in assumptions and orientations toward technopolitical action. It is this unboxing and remaking into tool kits for assembly that I examine more closely here. Multiple tool kits address how to develop observant digital practices, including how-to guides for erasing your internet profiles, how to become anonymous online, how-to instructions for undergoing a data detox, and how-to guides for building a DIY bulk surveillance system.[2] In this sense, tool kits not only provide instructions and materials but also indicate how to live with, through, and against these technologies. Tool kits provide instructions not just for assembly and use but also for attending to the social and political ramifications of digital devices.

Citizen-sensing technologies present a similarly complex set of instructions, practices, relations, and politics. Many of these technologies monitor environmental variables, such as air or noise pollution. Air quality monitoring tool kits can be found in multiple forms, which do not even necessarily include digital devices. Indeed, there are long-standing practices of working with diffusion tubes to monitor nitrogen dioxide. Small plastic tubes can be affixed to lampposts and street signs across an urban area and then sent to a laboratory for analysis. These low-cost analog devices provide a monthly average of nitrogen dioxide levels and can give an indication of pollution levels in an area. These monitoring practices often also include instructions for how to undertake a campaign for improving air quality, together with technical instructions for installing diffusion tubes and analyzing data. The tool kits that assemble along with these devices can be oriented to community organizing and local activism, urban design and traffic interventions, collective mappings and town-hall meetings, and problems of digital functionality. These aspects of tool kits are no less important, yet they do have a tendency to recede from view when the focus is on learning the technical aspects of digital monitoring technologies.

Citizen sensing is another set of such technologies and practices for monitoring the air that are often bundled into tool kit form. These digital technologies are used to monitor and measure environmental problems and to generate data that could be actionable for policy and regulation. The rise of citizen-sensing practices and technologies could in one way seem to activate instrumental—or, in other words, potentially reductive and functional—approaches to citizenship and political engagement.[3] Yet, in another way, these instruments in the form of low-cost environmental sensors could rework what might be seen as instrumentalist approaches to politics to develop new vocabularies of effect and effectiveness and to challenge the apparently linear logic of these instruments through the more knotty and wayward operations of attempting to realize political change.

The seemingly straightforward practice of monitoring environments with sensors, which in turn is meant to activate political change, rarely—if ever—unfolds in such a straightforward way. Nor does citizenship magically emanate from the use of these devices. The uptake of citizen-sensing devices, then, triggers a critical set of questions: Which modes and practices of citizenship do these digital technologies activate, legitimate, reproduce, or transform, and who is able to operate as such a digital or sensing citizen? If the how-to aspect of these technologies is meant to guide not just the construction of sensors but also the construction of environmental citizenship, then how do sensors influence relations and responsibilities toward environments? And if the use of citizen-sensing devices does not lead to straightforward outcomes, then how do these practices instead generate open-air instrumentalisms? These questions inquire into whether citizen sensing achieves its stated outcomes and realizes its hoped-for effects, or whether different engagements unfold along the way that rework the operations and relations of these instruments. At the same time, these questions consider who gets to be recognized as a citizen and how or whether sensing technologies reproduce the inequalities that often characterize citizenship.

This investigation into How to Do Things with Sensors is in another way a shadowy proposition for practice-based research. Rather than undertaking an ethnographic study of citizen-sensing projects, this research works through involvement with sensor technologies, communities, environmental pollution, and political processes as a way to understand these forms of action. By working with and through practice, it is possible to query the promised effects that sensors are meant to have and to test the forms of political engagement that take hold. Yet these are also practices in the making, where technologies, citizens, and political effects are not sedimented into stable form. Practice-based research is a way to inhabit and also shape these dynamics through inquiry.[4] This research examines the practices that assemble for using citizen-sensing technologies. It considers the insights or data that these technologies generate about environmental problems. And it investigates how new forms of evidence might be mobilized to improve environmental conditions.

While these orientations might seem to point toward instrumental relations in the sense of straightforward outcomes or effects, they instead give rise to expanded understandings of instrumentalism that are more aligned with a pragmatist and practice-based approach to instruments and ideas. Practice-based engagements with citizen sensing can put these questions to the test within specific situations and in relation to distinct environmental problems. They demonstrate how technologies in practice give rise to particular ways of organizing action and generating effects that are never as straightforward as they might initially seem. These points of practice guide this investigation into citizen sensing, where tool kits have been tested and installed in numerous settings and with a wide range of participants. This how-to guide unfolds in part through recounting experiences and experiments in practice that emerged from working with environmental sensing technologies.

Getting Started: An Incomplete List of Sensor Kits

Let’s look more closely at a few citizen-sensing technologies to consider how these practices are meant to present alternative strategies for documenting and acting on environmental problems. While only a few forays into the many sensors available for environmental monitoring are addressed in this how-to investigation, there is an extensive array of citizen-sensing projects that have been variously reviewed, assessed, tested, and assembled throughout the course of this research. These attempts at getting sensors up and running, developing sensor kits with communities, and working with sensor data inform this estimation on how to do things with sensors.

The focus here is on monitoring air quality. Yet there are many more sensors for monitoring water, noise, vibration, temperature, humidity, wind, heat, energy, radiation, soil, and vegetation. Water quality can be monitored through conductivity, temperature, and total dissolved solid sensors like the CaTTFish, and water levels can be monitored through ultrasonic sensors like the Flood Monitor.[5] There are Pocket Geiger sensors for measuring radiation[6] and DIY seismic sensors for measuring earthquake activity.[7] Moisture sensors monitor the health and presence of vegetation,[8] and temperature and humidity sensors monitor beehives and ensure the health of honeybees.[9] One of the earliest and most long-standing uses of DIY sensors has been in the area of monitoring air quality. Numerous sensors are now in circulation for monitoring air, from the DIY to those sold as finished products.[10] An incomplete list of operational, obsolete, and speculative citizen-sensing devices and tool kits for monitoring air quality includes

Aclima
Airbeam
Airbox
Aircasting
Air Quality Egg
AirSensa
Air Sensor Toolbox
AirVeda
AirVisual
Alphasense Sensors
Area Immediate Reading (AIR)
Array of Things
Atmotube
Awair
Breathe Cam
Brizi
Cair Smart Air Quality Sensor
Citizen Sense Kit
CityAir App
Clarity
Clean Space Tag
Common Sense
DR1000 Flying Laboratory
Dustbox
DustDuino
Dylos
EarthSense Zephyr
Float_Beijin
Flow, Plume Labs
Foobot
Grove Air Quality Sensor
hackAir
IGERESS
InfluencAir
iSPEX
LaserEgg 2
LifeBasis
LondonAir App
Luftdaten
MicroPEM
Netatmo
NOKLEAD
PANDA
Plantower
Plume Air Report
PuffTrones
PurpleAir
PUWP (Portable University of Washington Particle monitor)
Safecast
SensorBox
Sensors in the Sky
Shinyei Particle Sensor
Sidepak Personal Aerosol Monitor
Smart Citizen Kit
Smoke Sense App
Soofa Benches
Speck
Tree Wi-Fi
Tzoa (Enviro-tracker)
WeatherCube
Wynd

Here are DIY sensors and off-the-shelf kits, wearables and desktop devices, as well as a few apps that double as sensors through the use of smartphones for monitoring or navigating environments. The assortment of sensor names variously suggests democratic initiatives, technical enterprises, environmental revitalization, research projects, and manga characters. The list of names further designates projects and products, communities and practices, locations and platforms. In other words, these tool kits do not de facto include certain components and exclude others. They are in varying states of composition and decomposition, salability and discontinued-ness, with different monitoring capacities.

Some of the companies or makers of the aforementioned sensors make avowedly apolitical statements, which indicates that the data the sensors collect are not intended to support political projects, nor are the data open to the collectors of air pollution data.[11] Other projects, such as the Dustbox developed through the Citizen Sense research group,[12] deliberately seek to investigate how or whether new types of political and environmental engagement can materialize with these sensors. Yet, for many of these projects, the focus is on the technical device as a way to variously organize, attract, and mobilize citizen participation and data collection. The problem of air quality is in part organized through the devices and practices that environmental sensors make possible. Monitoring air pollutants, collecting data, and communicating evidence about elevated pollutant levels could be seen to be instrumental approaches to air quality, which these instruments facilitate. The instruments and instrumentality of air quality unfold in relation to this broader proliferation of sensors and sensor citizenship. Yet these are open-air instrumentalisms that do not follow a unilateral trajectory.

In this incomplete list of citizen-sensing projects and technologies, you might notice that some of the devices are ready-made and some require assembly. Some devices are “locked down” as consumer products, while others require ongoing tinkering and maintenance. Several of the sensors included in the preceding list are beta-stage and prototype technologies that have particular idiosyncrasies and require adjusted setup, troubleshooting, and puzzling over how to work with the data that they collect and present. Over the course of this research, sensors available in makerly form have increasingly crept toward a more settled product-like state, and in the context of the Internet of Things, several plug-and-play sensors are now available. Yet, if you have worked through building and setting up air quality sensors, you are inevitably left to wonder about how or whether such off-the-shelf devices are calibrated, how to access and analyze data, and whether data can be used to support claims about environmental pollution.

This scan of air quality devices and practices is also incomplete because sensors, and especially air quality sensors, continue to multiply and expire within the usual fleeting time spans of electronic devices. As soon as sensor technologies and projects are identified, new devices emerge, and others lapse into obsolescence. Some of the air quality sensors in this list are new, some are prototypes no longer in use, and some are dead devices that would require considerable effort to reboot and plug back in to operable systems. As with many tech projects, once technologies sediment into stable forms, they seem as readily to disappear or cease functioning, with websites flickering into oblivion, firmware updates colliding with hardware configurations, and peripherals no longer communicating across ports.[13] But this observation also jumps ahead, because it points to a few things to keep in mind when starting to use citizen-sensing tool kits. First, it is worthwhile to discuss briefly how sensor kits are configured as cosmologies of sorts.

Flat-Pack Cosmology

The modular instructions and diagrams for assembling tool kits demonstrate a distinct approach to problems, where relevant components are gathered together, documented, and assembled into an entity that will address the problem at hand. Think of the flat pack that consists of an itemized inventory of parts, including atomized images of assembly, with connecting actions signaled through arrows segueing across framed sequences toward a clear outcome. Similar to many modular products that can now be purchased and assembled with apparent ease, a certain flat-pack relationality is operationalized through sensor tool kits, where all the items needed for completion of the project need only be joined together by following straightforward instructions. What begins to unfold in this approach to tool kits and instructions, actions and outcomes, is a flat-pack cosmology, where the speculative universe of an environmental problem, for instance, assembles into a neat diagram of constructable relations held together through air quality sensors.

Cosmology is a term used by Whitehead to describe a metaphysical system that captures a universe of relations that is at the same time undergoing processes of transformation.[14] Cosmology also has a longer history of use within indigenous theory and practice as a term and concept that refers to sharing or holding experiences, connections, and activity in common.[15] While flat-pack cosmology is inevitably a heretical use of the term and concept, it indicates how the tool kit as a distributed and connected system forms and works, including the ways in which entities develop, how relations join up, how societies materialize, and how these varying components unfold and are sustained because of the values attributed to technology, especially in modular form. The difference, however, is that for Whitehead, cosmologies endure in the realm of abstraction and are drawn into the experiences of actual entities. Nevertheless, the characteristics of experiencing subjects, whether sensors or humans, express a cosmological system of relations under way. Stengers makes such a move in her multivolume text Cosmopolitics, where, through investigating the history and philosophy of science, she demonstrates the ways in which scientific and technical practices make particular worlds hold together, and to what effect.[16] Cosmopolitics, then, describes how these systems of technoscientific relations have political effects, and how they come down to earth.

From cosmology to cosmopolitics, Whitehead and Stengers provide reference points for engaging with the diagrams of relations that tool kits call into being. Tool kits offer up a particular way of concretizing maker-subjects, items for construction, modes of assembly, models of action, modes of becoming, desired outcomes, and ways of holding things together, or binning it all away. Tool kits are ways of organizing problems and relations for action, and even when the point is to crack open the black box of a sensor technology, the component parts that result from such crackery are configured in particular ways to allow for new modes of assembly. This taking apart and putting together, constituting and reconstituting of entities is indeed a salient characteristic of tool kits, which, on one hand, are notable for their modularity—their flat-pack-ness—and, on the other hand, need to be sufficiently open to be adaptable to new circumstances and uses.[17] Tool kits, especially air quality monitoring tool kits, are at once procedural and contingent arrangements. Indeed, the procedural method becomes quickly troubled in the flurry of calculating how to work with kit and in the open air of environmental monitoring. The next section details these points of procedure as well as how they go awry.

Ten Points for How to Construct Tool Kits

When starting off with a citizen-sensing project, one of the first things that many people will wonder about is how to construct a monitoring tool kit, keeping in mind that a tool kit is always more than just a collection of sensors. Some citizen-science tool kits more extensively outline techniques for learning protocols, organizing collection efforts, analyzing data, and influencing policy than the finer details of technical kit configurations.[18] Here are a few notes that outline some of the key considerations when beginning your project. After you have read these notes, we will look at a few sample projects that will give you a more detailed sense of how these points could be implemented.

1. What is a tool kit?
The first thing to keep in mind when doing things with sensors is that these typically makeshift instruments will give rise to questions about the purpose, the composition, and the coherency of the technology under investigation—but never in such a philosophical way. Instead, the question will arise in the middle of attempting to get sensors to work. The refusal of electronics to function as a key part of a sensor tool kit will reveal the limited effect and scope of these devices. The eventual functioning yet occasionally inexplicable output of sensors will make one wonder at the apparent achievement of obtaining a connection. Sensors have not necessarily, as Simondon would suggest, become sufficiently integrated so as to seem “natural” within their own self-generated milieu.[19] Instead, they are often troublesome contraptions that would consume your time and energy as you attempt to find an operative pathway to citizen engagement. Sensors, you might discover, are just one particular entry point for engaging with air pollution, which is also interconnected with environmental public health, development, community organizing, and environmental justice.
2. Which sensor should you use to monitor the air?
This is a question I am often asked by people interested in beginning to monitor with sensors. The answer is, it depends. This is the second note on how to do things with sensors. The sensor you choose to use depends on whether your interest is to tinker with electronics, to plug in a device without having to modify it, to focus on collecting “accurate” environmental data, to map and share data with a wider monitoring community, or to focus on a particular air pollutant of concern. These are not always mutually exclusive objectives, but often the focus will be placed on one priority area more than another.
3. What are the parts you will need?
The third note about how to do things with sensors is that most guides will begin with a seemingly comprehensive list of parts. Photographs of parts show neatly arranged and brightly colored LEGO-like electronics that beckon for a makerly connector to join them up. The parts will include jumper cables and wire ties, Velcro and tape, breadboards and LEDs, microcontrollers and gas sensors, potentiometers and buzzers, 9-volt and lithium batteries, and resistors of various sorts. This list of parts is assembled in different ways, but the basic components include electricity and computation, held together through digital infrastructures. This is less a sensual universe of the four elements and more a functional universe of the many efficiencies. As noted, I call this how-to universe the flat-pack cosmology. The flat pack seemingly includes all the parts and instructions you will ever need to realize your objectives. However, just as your cosmology of electronics begins to assemble, you will discover that a part is missing or that the comprehensive list of parts defines sensing in one way, such as how to pass voltage along a wire, and not another, such as how to convert voltage into a semiaccurate measurement of pollution levels. The cosmology of flat pack is then always in process, splintering into multiple cosmologies of what the how-to kit might enable or open up.
4. Where should you begin?
The fourth note when working with sensors is that you are most likely better off diving in and tinkering with a bit of kit before you assiduously read the instructions or absorb extensive advice. The intricacies of pins and holes, cables and ties, are best encountered through physical proximity rather than secondhand reports. Turn to forums and videos once your brain is on the bake, the electronics refuse to talk, and you are sufficiently prepared for the curious if unique hybrid of geekery and spleen that often pours forth from makerly FAQs. Your virtual interlocutors will frequently declare, “No, I will save the planet first, and it will only be through my bespoke circuit diagram!” The how-to should, for this reason, be approached with caution in the face of such zealotry.
5. How do you make a working sensor?
The fifth note on how to do things with sensors is that the device you are working with is likely to be in need of upgrades and updates before you have even begun. The instructional guide that you are following will recommend software or hardware that will no longer be available or will be out of date. The microcontroller hardware will have been updated to a newer version. You can start with an Arduino microcontroller, to discover that the software libraries to be loaded on your Arduino no longer function with your microcontroller version. The entire configuration of the sensing kit will have shifted so that a new iteration needs to be developed through the very making and following of instructions. To do things with sensors, then, you need to trudge through states of nonconnection and electrical blank spots. Lights will refuse to flash, data will decline to post, and URLs will flash 404 where platforms should appear. The online forum and the FAQ section will become your most helpful resources in these early states. There you will find the near-time updates and fixes that will come to your aid as you bodge your way toward a working sensor.
6. Are we there yet?
The sixth note is that a sensor tool kit will never be complete. It is a roving arrangement of stuff that will need to be topped up, updated, supplemented, extended, and hacked together. A tidy toolbox will soon become the site of a mass spill event. A clear desk will conceal an essential cable. Online warehouses will become ever-expanding otherworldly depots, where making and remaking require just one more trip to the webby aisles of Cool Components. Where does the necessary kit for undertaking a citizen-sensing project begin and end? This question could forever remain unanswered.
7. What should you do with the data?
The seventh thing to consider is that once you have built your sensor, you will need to post your data and map your monitoring locations. This process can take place on a platform that you develop along with a sensor device or on an externally developed platform that may or may not last the year. Once platforms expire, your device will likely require an entirely new configuration to pipe data to another platform. Some platforms require inputting latitude and longitude to mark fixed locations. Other platforms track the routes and itineraries of sensors used in more mobile ways. Platforms can also include the outputs of sensor data, which are presented in a wide variety of formats, from raw voltage counts to units converted to regulatory standards of parts per million (PPM) or parts per billion (PPB) or micrograms per cubic meter (µg/m³). Pollutants monitored could include gases and particles, from nitrogen dioxide to particulate matter. These different ways of presenting and engaging with data raise multiple other how-to questions about how to analyze data sets, how to generate evidence, how to communicate findings, and how to influence policy. A successfully connected sensor, as it turns out, will be the least of your problems once you move to the domains of platforms and data.
8. How should sensors be used in the field?
Now that we’re well on our way to making your first citizen-sensing tool kit, here’s the eighth thing to remember: if your plan is to monitor environments, you will eventually have to move from the desktop and workshop to the open air, where sensors will be used in situ, over time, and in a range of conditions. You might have bashed together a passable device consisting of a metal oxide sensor, breadboard, jumper cables, and resistors, all activated by a lithium battery. You might even have mapped or located your device on an online platform, thereby giving your project an apparently global reach. However, there are still yet more instructions that could be written for how to undertake pollution sensing, which necessarily extend once sensors are taken out into the open air. This guide, then, attempts to account for the contingencies, experiments, and openings that occur through such open-air instrumentalisms.
9. How do you register pollution?
Assuming that the purpose of putting together sensors is to monitor environments, then a tool kit assembled for addressing air pollution will also ideally need to address practices of environmental observation and engagement. Note 9, which would even precede note 1, is that although it can be quite easy to get bogged down in making sensor devices work, the milieus of these technologies necessarily comprise events such as how pollution registers or might register—including in existing monitoring networks, asthmatic bodies, or regulatory violations—and how communities become involved in attempting to address the problem of air quality. The scope of your tool kit might need to be redrawn so that the environmental, social, and political aspects of monitoring are as much an area of study as attempting to create a blinking LED.
10+. How do you create a community monitoring project?
Note 10 sprawling to an indefinite number of notes is that once in the open air, you will encounter endless considerations for how to make sense of your attempts to monitor air pollution. This list of further things to consider includes the following: Which air pollutants are you monitoring? Where are the likely sources of emissions? Which monitoring protocols and methods will you follow? Have you calibrated your sensor? How often and for how long will you collect data? Will your monitor be stationary or mobile? How many locations are in your monitoring network? How will you compare data across monitoring locations? How will you compare your data to other regulatory or reference monitors? In which measurement units will you present your data? How will you analyze your data? With whom will you share your data? What do you hope to change, improve, or challenge about monitored environments? With which organizations or regulatory bodies might you collaborate to act on findings from community monitoring? Think of these points as a guide that can be read alongside examples of citizen-sensing installations and in relation to your own monitoring project.

Although this section is first arranged as a ten-point plan in keeping with the exigencies of the how-go genre, it then quickly unfolds into an open-ended set of considerations when attempting to monitor pollution. As this preliminary list of overarching points related to assembling sensors for citizen monitoring demonstrates, any actual monitoring project that goes beyond the initial assembly of sensors will encounter situations that can be specific to the environments monitored. Although these tips could be presented as a set of instructions or as a checklist for how to go about monitoring, they are also far from definitive in terms of addressing the particular conditions that could arise when undertaking environmental monitoring. In the process of following these instructions, you might have learned that the assembly of sensors is far from straightforward, the composition of a tool kit is neither fixed nor complete, the posting of sensor data can come in many forms, the analysis of data is an area of ongoing development, the protocols and methods for monitoring are often still in process, the “citizens” who would monitor are often differentially able to make their voices heard, and the environments to be monitored will make specific demands upon how data are collected, presented, and turned into evidence. When following any instructional guide for sensors, you will find that open-air instrumentalisms abound.

This is not to say that it is not possible to operationalize environmental sensors for detecting pollution and gathering data. Multiple low-cost and DIY sensor projects are now in place that continually collect data and generate particular accounts of environmental processes. However, these practices are provisional and full of necessary work-arounds.[20] Inevitably, more than a few how-to guides for using sensors will present this process as a rather simple and matter-of-fact situation.[21] This how-to guide suggests, conversely, that by attending to the deviations from the straightforward approach, you could find that many more engagements with sensors, environments, and politics emerge that remake the operations of instruments and instrumentality. Open-air instrumentalisms in this way are to be valued, because they are the process through which technopolitical experiments and more just environmental collectives could coalesce. More will be said about this point in the sections that follow. Now, let’s turn to look at a few detailed examples and experiences of assembling sensors for testing and eventual use in the field. A few things to ask along the way are, How does a tool kit expand or shapeshift along with differing uses? What other considerations come to the fore when attempting to monitor actual air pollution near an industry site or in a congested city? And in what ways does the how-to expand from technical delineations to indicate that these practices have been political all along?

How to Connect Sensors