Chop-Chop: Faster, Pussycat! Kill! Kill!
Master of Interaction Design Program, K3, Malmö University, Sweden
This paper describes an embodied interaction critical design
project stemming from a brief to ‘design an accident’. Chop-Chop
is a self-tracking Internet of Things (IoT) smart knife system
designed to simplify life, better yourself and save you time
through coaching you to become the fastest chopper. The system
was created with the goal of sparking a debate around how the
current state of smart products improve our lives (or not). In this
paper embodiment refers to the body of data formed over time by
the digital traces left by anyone using Chop-Chop. The question is
what the resulting agency and privacy implications are.
Additionally we attempt to understand what biases and power
relationships are embodied when making objects ‘smart’? We
argue that raising awareness around such topics is more relevant
than trying to create the ‘best’ smart knife on the market. Lastly
we argue that critical design should venture out from the gallery
spaces into the real world. There is a need for discussions and
raised awareness involving a broader spectrum of stakeholder
perspectives to help incite change regarding IoT agency and
privacy issues, including political and judicial aspects.
• Human-centered computing • Interaction Design ·
Interaction Design theory, concepts and paradigms.
Critical design, smart knife, user awareness, tangible interface,
agency, privacy, IoT.
The critical design Chop-Chop smart knife system stems from a
brief to ‘design an accident’ and is the result of a collaborative
effort by a group consisting of Delia Albu, Nicole Carlsson, Raya
Dimitrova, and Katrine Lynggaard.
The Internet of Things (IoT) market has been projected to grow
rapidly in the near future, spurred on by the premise of helping
people achieve a safer, easier, more efficient, comfortable and exciting
lifestyle. Technology wise IoT involves embedding sensors and
actuators into everyday objects (things), connecting them to the
internet and enabling them to send and receive data.
The Chop-Chop smart knife system is situated in the IoT smart
home sub category. Typically products in this category fall under
four main groups: entertainment, energy, security and healthcare.
Healthcare smart products often provide a person with coaching
or the ability to self-track or visualize a quantified self. An
example of such a product is Aira smart scales by Fitbit , see
fig. 2, with the tag line “Smarter Scale. Better Results”. Aira
syncs wirelessly and automatically via Wi-Fi, tracks weight, body
mass index (BMI), lean mass and body fat percentage. It displays
easy to read charts and graphs of your stats and works with the
Fitbit app to help set calorie goals and achieve them through
Figure 1. Aira smart scales
Another example is the soon to be released Hello Egg kitchen
assistant by RnD 64, see fig. 2, a large voice-powered egg-shaped
kitchen assistant with a small reflective screen. Hello Egg is
described as “your home-cooking sidekick that liberates you from
the throes of mundane decision-making and frees up an extra day
off for you every month”. It plans your weekly meals
according to your dietary preferences, organizes your shopping
list, orders the produce delivery and provides you with easy-to-
follow step-by-step voice-navigated video recipes.
Figure 2. Hello Egg kitchen sidekick
The term embodied interaction was coined by ethnographer
Dourish , at Xerox Park in 2001, urging researchers/designers
to get out of the lab into the real world to include the physical and
social realities of human computer interaction. The approach for
embodied interaction in this paper is opened up to also refer to
“materiality”. Specifically we are referring to data bodies
generated over time through a person’s interaction with a system.
With IoT, whether a person is aware of it or not, sensors are often
programmed to register everything you say and do in order to
provide functionality. The resulting data body is stored, most
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often in cloud(s), representing a digital embodiment of a person.
Over time, a detailed profile of a person will be built up, as
algorithms process, cross-reference, analyze and categorize the
data. I.e. bodily interactions with systems are recorded, saved and
stored as digital information, (mis)representing a person, often
without that person’s knowledge or consent. These systems tend
to be of a black box nature in terms of data handling. It is often
not clear when and where data is stored or collected. In general,
laws concerning who owns data are not straightforward. In the
United States user data is owned by the collector, but in Europe
and most other countries user data is the property of the user. Data
Protection Regulation (European Commission 2012) in Europe
defines “personal data” as any data that can be related to
A common definition of privacy, dating back to the 1890s, is the
fundamental principle that every person legally has “The Right to
be left alone”.
As Chop-Chop is situated in the home, a place where privacy is
expected, we attempt to raise a discussion around what the
resulting agency and privacy implications (of a self-tracking smart
product situated in the home) are. Additionally we attempt to
understand what biases and power relationships are embodied
when making everyday objects, such as a knife, ‘smart’?
2. CRITICAL DESIGN
The term critical design has emerged as an attention receiving
design approach within the HCI field. Dunne and Raby, with
roots in The Royal College of Art (RCA), London, coined the
term and themselves describe it as design that “rejects how things
are now as being the only possibility, it provides a critique of the
prevailing situation through designs that embody alternative
social, cultural, technical, or economic values” .
Critical design has however come under scrutiny for not
delivering on its promises. Oliveira and Prado  make the point
that critical design has become too “spoiled and self-centered”
and is missing the mark by not venturing out of the safe and
limited confines of academia, museums and art galleries.
According to them preferable developments for the field would
involve making the “tricky questions at hand more tangible and
visible” to the public. They also stress that a dialogue with the
mainstream and mass-culture using less cryptic language is
needed. Through this, critical design could be more effective and
possibly even transform into a political agent, according to
Oliveira and Prado.
Below is a review of selected related work in the critical design
genre to help situate Chop-Chop in the interaction design space.
2.1 The Placebo Project
In the Placebo Project, see fig. 3, Dunne and Raby experimented
with taking design research into everyday life. They devised 8
prototype objects and placed them with volunteers found through
adverts, workshops and window displays. The aim was to find out
if people are more receptive to radical ideas than the industry
acknowledges. A non- scientific informal process, aware of
ethnographic and anthropological methodologies, was used. As
they used real people, although self-selected, the findings were
grounded in reality.
Figure 3. The Placebo Project from Dunne and Raby (2001)
2.2 Uninvited guests
Anglo-Indian design practice, Superflux, created Uninvited Guests
 , a short video effectively exploring the frictions between a
one-size-fits-all IoT smart elder care system. It shows the daily
life of Thomas, 70, having been given a smart device system by
his children to help him stay healthy by eating and moving as
suggested. When not following the suggestions the systems
nudges him via a mobile app and his alerted children sms him to
ask him if he is ok. This work empathically portrays what it might
be like to not have a say in what you eat or how you move any
longer as an older person, “cared for” by a smart system. The lack
of agency and privacy is disturbing. In the end Thomas cleverly
hacks the system by tricking the sensors, but what type of future is
this, spending your day fooling sensors so you can spend time as
Figure 4. Uninvited Guests from Super flux (video still) (2015)
We developed a series of critical prototypes on the theme of smart
knives; these took the form of a website1 and physical devices
with tangible interfaces (3 bespoke knives and a cutting board).
During a demo hour people experienced the prototypes.
Chop-chop is a smart knife system which senses how fast you
chop and prompts you to alw