smoon: A Spoon with Automatic Capacity Adjustment
WATANABE, Keita1, SATO, Ayaka1, MATSUDA, Shota1 INAMI, Masahiko1, IGARASHI, Takeo1,
Japan Science Technology Agency, ERATO, IGARASHI Design UI Project, Tokyo, Japan{watanabe, sato, matsuda}@designinterface.jp, inami@inami.info, takeo@acm.org

Keywords-component; Measuring; Kitchen; Interaction
Design; Physical Computing;I.

INTRODUCTION

Today, vast amounts of knowledge are stored andshared on the Web. We can now obtain a variety ofinformation on the Internet anytime and anywhere byusing a mobile device, and we can perform various tasks
using such information. For example, if you want to cooksomething, you can find a huge number of recipes onrecipe websites. However, this digital cornucopia stops at
the border between the digital and real world; i.e., thecooking itself is not automatic, and we have to physicallycook a meal by ourselves. In other words, the informationon the net (e.g. recipe) has to be transformed into aphysical entity (meal) indirectly through manual labor(Figure 2). This indirect process makes suchtransformations inaccurate and tedious.
Our goal is to develop a computational device thatconverts data on the net into a physical entity directly withas little human intervention as possible (Figure 1). In thispaper, we present a novel measuring device called smoon(smooth + spoon) (Figure 1) that frees the user frommaking manual measurements as an initial experimenttoward achieving this goal. Smoon automatically adjusts
its capacity based on the provided recipe data, and users
can measure out accurate amounts of ingredients simply
by scooping: there is no need for them to pay attention to
the quantity or units specified in the recipe.

3

Change volume
CHARACTER LCD
Linear actuator L-12(Firgelli Inc.)

30
ml
4060

280

7050

ArduinoActuate servo motor
UNO

120

130

ARDUINO

140

90

Abstract— People often cook meals while referring a recipe,
and following a recipe usually involves frequent
measurements of ingredients. The measurement process
involves converting numerical data in the recipe intocorresponding amounts of physical ingredients, but thisprocess is tedious and prone to error. We devised a meansby which a robotic system directly converts numerical dataon a digital recipe into physical quantities and built a
prototype measurement device called ‘smoon’. Smoon is arobotic measuring spoon that physically transforms itself tochange its capacity according to recipe data stored in acomputer or on the Internet. This system allows the user tocook a meal with a simpler workflow. The user obtains
accurate amounts of ingredients simply by scooping: there isno need for him or her to pay attention to the quantity orunits specified in the recipe.

10011011Get ingredient’s
volume dataDigital recipe

Figure 1. Structure of smoon. An actuator physically changes thevolume to match digital recipe data.

II.

RELATED WORK

Various kitchen projects using information technology
have been undertaken in the field of human-computerinteraction. For example, navigation systems for cooking
are very popular topics of study [1, 2, 3, 4, 5]. Thesesystems teach the user the next action at the appropriate
timing and allow them to share the context with others byshowing information with a projector or embedded LCD
display in the kitchen. These are navigation techniquesthat make the user understand the procedure and cook ameal efficiently. However, they do not assist users
physically, and users need to perform all of the physicalactions by themselves.
III.

PROTOTYPE OF SMOON

Smoon is a robotic measuring spoon that physicallytransforms its capacity in accordance with recipe datastored in a computer (Figure 1, 3). The recipe can beobtained from the Internet. The current prototype is a
modification of Nuscup, an adjustable measuring spoon
developed by Dalla Piazza Inc. [6]. We used a 17-cm
spoon and embedded in it a linear actuator L-12 (FirgelliTechnologies Inc.) to change its capacity. In addition, weattached a LCD character display (LCD104B6B) tosmoon. The actuator and LCD are controlled by amicrocontroller Arduino. Smoon also has a button on its
side to control the recipe. In this implementation, smoon
is capable of measuring 0 ml to 120 ml of ingredients. It
takes approximately 7 seconds to change its capacity from0 ml to 120 ml.

WATANABE, Keita & al., smoon: A Spoon with Automatic Capacity Adjustment

Readjust

Ordinary
Cooking process

Readinstructions

Selectmeasure tool

Scoop up
ingredientsml, g, cc, cups
table spoon, tea spoonCooking processwith smoon

Knowcurrent the instruction

Measureingredients

Put
into bowl

Too much, Too few,
Need horizontal place

Put
into the bowl

Scoop upthe ingredients

Figure 2. Comparison of cooking workflow with and without smoon

A. Smoon recipe
Smoon allows the user to perform measurements
without any additional effort, but it does not free the userfrom having to pay attention to timing or order. We
therefore implemented the smoon recipe application on atablet computer (Figure 2). The smoon recipe is aslideshow application that shows the cooking process stepby step. The main feature of this recipe system is that it
divides a cooking procedure into individual steps of
putting ingredients or materials in pots and pans andshows each step as a slide in order to link smoon to therecipe. Smoon only shows minimal recipe instructions tothe user. For example, it only shows “Pour milk into thebowl”, and it does not show amounts or units such asgrams. Moreover, a Smoon recipe is capable of handlingingredients whose amount is specified by mass. For
example, whereas wheat flour and sugar are usually
measured by mass, smoon can only measure volume.
To solve this problem, a smoon recipe automaticallyconverts mass into volume. Smoon can measure various
materials in this way. In addition, if the total amount ismore than a single scoop, the system automaticallycomputes how many scoops are necessary and presents
the information to the user. For example, if the user needs
to obtain 300 ml of ingredients, the smoon recipe asks theuser to scoop three times while appropriately changing its
capacity (100+100+100). In the current implementation,
the developers manually made the recipe data andconverted units. Our future work will be to convert

arbitrary cooking recipes on the Internet into smoon
recipes.
B. Workflow with Smoon
Smoon skips tedious actions in a cooking workflow.
Figure 3 compares cooking workflows with and withoutsmoon. A notable point in the smoon workflow is that theusers simply scoop the material into a pot or pan and no
additional actions are necessary. The user does not haveto think about the amount of ingredients or the units.
IV.

We developed a robotic measuring spoon called smoon.
Here, we described the current implementation and itsrecipe system. Smoon simplifies the process of cooking
using digital recipes. The main idea behind this work is toconvert digital data directly into physical entities to be
used in physical tasks. Cooking was just an example. We
plan to explore this idea further in other domains in thefuture. For example, we could explore the use of a smart
screwdriver that changes its size and shape from plus tominus based on instructions given in assembly manuals.
REFERENCES
[1]

[2]

[3]

[4]

[5]

[6]

Figure 3. The “smoon” system. The user does not need to careabout the amounts of the ingredients since the recipe data actuates
the measuring spoon directly.

CONCLUSION

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Nuscup, Dalla Piazza Inc.
http://www.dallapiazza.com/nuscup_01.asp