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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>The BAALL Ontology - Configuration of Service Robots, Food, and Diet</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Bernd Krieg-Brückner</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Serge Autexier</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mihai Pomarlan</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Collaborative Research Center EASE, Universität Bremen</institution>
          ,
          <country country="DE">Germany</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>German Research Center for Artificial Intelligence</institution>
          ,
          <addr-line>DFKI, BAALL, Bremen</addr-line>
          ,
          <country country="DE">Germany</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The BAALL Ontology, originally motivated by Ambient Assisted Living, now comprises more than 40k OWL axioms to integrate diverse applications, covering a foundational, a variety of general, and several application domain ontologies for configuration of service robots, diets, structured food products and dishes, and cooking assistance. To maintain structural consistency, safe ontology extension is supported by Generic Ontology Design Patterns.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;service robots</kwd>
        <kwd>food</kwd>
        <kwd>diet</kwd>
        <kwd>generic ontology design patterns</kwd>
        <kwd>qualitatively graded relations</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
    </sec>
    <sec id="sec-2">
      <title>2. Structure, Foundation</title>
      <sec id="sec-2-1">
        <title>MEDICINE</title>
        <p>• Disease
• RestrictedDiet</p>
      </sec>
      <sec id="sec-2-2">
        <title>PERSON</title>
        <p>• hasDisease
• isAllowedDish</p>
      </sec>
      <sec id="sec-2-3">
        <title>DIET</title>
        <p>• DietRestriction
• allowsFOD
• allowsDish</p>
      </sec>
      <sec id="sec-2-4">
        <title>FOUNDATION</title>
        <p>• Universal Concepts
• “Upper Ontology”
DUL
(DOLCE Ultra Light)
without Axioms</p>
      </sec>
      <sec id="sec-2-5">
        <title>BIOLOGY</title>
        <p>• Eukaryota</p>
      </sec>
      <sec id="sec-2-6">
        <title>CHEMISTRY</title>
        <p>• ChemicalCompound</p>
      </sec>
      <sec id="sec-2-7">
        <title>PHYSICS</title>
        <p>• PhysicalQuantity</p>
      </sec>
      <sec id="sec-2-8">
        <title>FLAVOUR</title>
        <p>• FlavourCompound</p>
      </sec>
      <sec id="sec-2-9">
        <title>ECONOMY</title>
        <p>• Price</p>
      </sec>
      <sec id="sec-2-10">
        <title>GEOGRAPHY</title>
        <p>• GeoRegion</p>
      </sec>
      <sec id="sec-2-11">
        <title>FOD_SOURCE</title>
        <p>• fromEukaryota
•
hasFlavourCompound</p>
      </sec>
      <sec id="sec-2-12">
        <title>FOD_INGREDIENT</title>
        <p>• hasSource</p>
      </sec>
      <sec id="sec-2-13">
        <title>FOD_PRODUCT</title>
        <p>• hasFODIngredient</p>
      </sec>
      <sec id="sec-2-14">
        <title>SHOPPING</title>
        <p>• ShoppingList</p>
      </sec>
      <sec id="sec-2-15">
        <title>OBJECT</title>
        <p>• PhysicalAspect
• hasIngredient
• comprises...</p>
      </sec>
      <sec id="sec-2-16">
        <title>ARTIFACT</title>
        <p>• PhysicalContainer
• CookWare</p>
      </sec>
      <sec id="sec-2-17">
        <title>DISH</title>
        <p>• hasLowValue
• hasHighValue</p>
      </sec>
      <sec id="sec-2-18">
        <title>COOKING</title>
        <p>• RecipeTask
• processFOD
categories, characteristic relations, and axioms are only introduced by Generic Ontology Design
Patterns when required, cf. Sect. 8.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Configuration of Mobility Assistants</title>
      <p>
        The BAALL Ontology was motivated by the project Assistants for Safe Mobility (ASSAM, www.
assam-project.eu) [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], where multifaceted variants of smart mobility assistants have been
developed on the basis of wheelchairs and walkers. These are intended to compensate for
individual age-related impairments: end-users may be aflicted by diseases leading to motoric
impairments (e.g. loss of endurance, visibility) or cognitive impairments (e.g. disorientation).
With appropriate hardware/software components, the mobility devices not only compensate
for motoric impairments, but also provide orientation and navigation assistance. This variety is
a considerable challenge for assessment and configuration.
      </p>
      <p>About 25 separate interlinked general domain ontologies have been developed (the layer below
Foundation, coloured red in Fig. 1) such as Medicine defining Disease, or Artifact defining
MobilityDevice as a subclass of Device.
Assistance: Intermediate Abstraction</p>
      <sec id="sec-3-1">
        <title>Person</title>
      </sec>
      <sec id="sec-3-2">
        <title>Disease</title>
        <p>affects</p>
      </sec>
      <sec id="sec-3-3">
        <title>Impairment</title>
        <p>impliesAbility</p>
      </sec>
      <sec id="sec-3-4">
        <title>Ability</title>
        <p>hasDisease
hasImpairment</p>
        <p>hasAbility
compensatedBy
requiresAssistance</p>
      </sec>
      <sec id="sec-3-5">
        <title>Assistance</title>
        <p>needsMobilityDevice
providedBy</p>
      </sec>
      <sec id="sec-3-6">
        <title>Device</title>
        <p>
          • Assistance providedBy Device
hasODnistoelaosgey_D1eSvleiglohptment Methodology – KSEM 2016
hasDisease_2Moderate Person
hasDisease_3Severe
Disease
hasDietRestriction_1Minor
hasDietRestriction_2Strict
requiresDiet isAllowedFOD_recommended
isAllowedFOD_1discouraged…
isAllowedDish_recommended
isAllowedDish_1discouraged
isAllowedDish_2denied
isAllowedDish_3forbidden
16
RestrictedDiet
allowsFOD_recommended
allowsFOD_1discouraged
allowsFOD_2denied
allowsFOD_3forbidden
Composite Configuration. To manage complexity, the relation needsMobilityDevice (Fig. 2)
is a stepwise composition of individual relations from Person to separately defined ontologies.
Individual Diseases of a particular Person are assessed, captured by the relation hasDisease. A
Disease may result in some Impairment modelled in the relation afects . In turn, an Impairment
impliesAbility an Ability; an Ability may be compensatedBy some Assistance providedBy some
MobilityDevice. For Disease, Impairment, etc., see [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ].
        </p>
        <p>Thus the relation needsMobilityDevice is sequentially composed, where each relation is a
“triangular” composition, e.g. requiresAssistance ∘ providedBy → needsMobilityDevice.</p>
        <p>It is suficient to model the individual relations afects , impliesAbility, etc., separately, and
once and for all; the rest is deduced by OWL-DL reasoners.</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Configuration of Diet: Qualitatively Graded Relations</title>
      <p>Similarly, the left-hand side of the diagram in Fig. 2 has been re-used and refined for the
configuration of diets, see Fig. 3.</p>
      <p>
        To achieve a graded valuation according to some qualitative abstraction of a semantic concept,
we introduce extra valuation domains with values such as 1Slight, 2Moderate, 3Severe, or some
other (arbitrarily fine) qualitative metrics; the number of levels depends on the application.
Qualitatively graded relations (cf. [
        <xref ref-type="bibr" rid="ref2 ref3 ref4 ref5">2, 3, 4, 5</xref>
        ]) encode such valuations in the names of (a sheaf
of) relations hasDisease_1Slight, hasDisease_2Moderate, etc.
      </p>
    </sec>
    <sec id="sec-5">
      <title>5. Structuring Food Products and Dishes</title>
      <p>In the case of diets, the object to be configured is Food or Drink (abbreviated as FOD in Fig. 3); a
Person is recommended, ..., or forbidden certain FOD, e.g. food products containing PorkMeat,
or pungent dishes for Gastritis or certain allergies.</p>
      <p>To facilitate such a modelling, the ontologies containing FOD and Dish are structured in an
onion-like fashion (Fig. 1): FOD_Source is the core, where e.g. PorkMeat is characterised as
isCutOf some Pig and fromAnimal SusScrofaDomesticus in the Biology ontology. Similarly,
FOD_Ingredient relates to FOD_Source only by the relation hasSource, and FOD_Product
to FOD_Ingredient by hasFODIngredient. A particular PungentDish can now be defined by
comprisesConstituent_2MediumHigh_or_greater_Intensity some PungentFlavourCompound,
etc. (Fig. 3). The BAALL Ontology is categorized on the basis of Eurocode-2 (EuroFIR), with
constituent relations to Aromas, the usual NutritionCompounds, and FoodAdditives (according
to the International Numbering System, INS).</p>
    </sec>
    <sec id="sec-6">
      <title>6. Cooking Assistance</title>
      <p>
        Early work on cooking assistance [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] has led to comprehensive modelling of Ingredients (cf.
Sect. 5). A recipe is a workflow of RecipeTasks such as preparation, baking, etc. Cooking is
modelled based on Ingredients with e.g. flavour properties, while RecipeTasks modify their
presence, e.g. when an aroma evaporates at a particular temperature. We hope to be able to
eventually predict a flavour composition in the final dish by “virtual cooking”.
      </p>
    </sec>
    <sec id="sec-7">
      <title>7. Organizing Knowledge for Robotic Activities</title>
      <p>
        The device configuration from Sect. 3 has later been refined by qualitatively graded configuration
(Sect. 4) and become the basis for configuration in robotics, sharing user and device profile
modelling, cf. [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>
        The structure of an episodic memory has been formalised for domestic service robots
performing everyday activities (see [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]) by an ontology engineering efort undertaken by the
EASE1 project, resulting in a set of ontologies referred to as SOMA [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. The focus of SOMA
is autonomous and cognitive robotics, a still emerging field, which diferentiates it from the
more industrially focused efort at standardizing robotic knowledge representation undertaken
by the ORA group [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. Researchers involved with the development of SOMA have built upon
knowledge and patterns formalized in the BAALL Ontology.
      </p>
      <p>An important use of episodic memories is to provide training data for a robot to improve
its performance—either by learning from its own activities, or from observing (records of) the
activities of other agents, e.g. humans demonstrating how a task should be performed. An
episodic memory must be organized so that it will contain at least some useful knowledge for
an observing agent, even if the recording agent is diferent in body and capabilities. Therefore
it contains views on an activity from diferent levels of abstraction, from recordings of sensor
inputs and control signals, close to the hardware, to more cognitively motivated sequences of
tasks in which entities in the world play roles while obeying restrictions pertaining to the task,
or placed on the entities by their own dispositions and/or capabilities. At this cognitive level the
rich ontology of RecipeTasks and Cookware from the BAALL Ontology is put to use in EASE’s
episodic memories.</p>
      <p>
        Gathering a rich variety of episodic memories requires an interdisciplinary collaboration
among roboticists, cognitive scientists, and neurologists in EASE1. This places further critical
requirements on the knowledge infrastructure that processes episodic memories. In particular,
there must be ways to verify that episodic memories entered into storage obey logical constraints
on what is a well-formed episode recording; also important is to check whether an episode
recording represents a “good run” of an activity – episodes of failure are an interesting source
of learning, as long as failure is recognized as such [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
      </p>
    </sec>
    <sec id="sec-8">
      <title>8. Safe Extension Using Generic Ontology Design Patterns</title>
      <p>
        Episodes and the other patterns above have been defined by Generic Ontology Design Patterns,
GODPs [
        <xref ref-type="bibr" rid="ref2 ref4 ref5 ref8">2, 4, 5, 8</xref>
        ], expressed in the language Generic DOL [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], an extension of the Distributed
Ontology, Model and Specification Language , an OMG standard (see omg.org/spec/DOL, dol-omg.
org), supported by the Heterogeneous Tool Set, Hets [10].
      </p>
      <p>GODPs structure complex ontologies, with local confinement of design choices, ensuring
safety for modelling and data with sanity checks on their input and generative internal
consistency for their interrelation. Thus they are very useful for maintaining structural consistency in
extensions of large ontologies, even by non-experts.</p>
      <p>We may e.g. define a pattern to extend FOD_Source with a new fish while relating it to
its counterpart in the Biology ontology; this anchor is important for correct translations to
common names in other natural languages, a likely source of error.</p>
    </sec>
    <sec id="sec-9">
      <title>9. Conclusion</title>
      <p>The BAALL Ontology is primarily used for semantic integration. Depending on the
application, several application domain ontologies provide restricted “views” to the structured
hyper-ontology (cf. Fig. 1). As examples consider Person importing Assistance and Artifact
for MobilityDevice on the one hand (cf. Sect. 3), or Person importing Medicine and Diet on
the other (cf. Sect. 4). Assistance for mobility devices, FOD, Diet, RecipeTask and Cookware
provide a fair coverage for extensive academic use; completeness for commercial use is not
claimed.</p>
      <p>The structured BAALL Ontology and some examples of application domain ontologies derived
from it can be found at http://ontologies.baall.de, freely available to the academic community,
with a dual licence for commercial use.</p>
      <p>
        It is presently being re-constructed by applying GODPs in a systematic fashion (cf. Sect. 8).
GODPs also support populating the BAALL Ontology by data in a safe way (cf. Sect. 8 and [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]),
e.g. for robot or human activity recordings (cf. Sect. 7), or for specific food products and dishes
(cf. Sect. 5).
      </p>
    </sec>
    <sec id="sec-10">
      <title>Acknowledgments</title>
      <p>
        We are grateful for their early contributions to Sidoine Ghomsi (aromas), Martin Rink [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ],
Philipp Kolloge (diet), Dmytro Kozha (shopping assistance), and Marc Robin Nolte (bakery); to
Mihai Codescu and Till Mossakowski (Generic DOL); José deGea Fernandez (configuration in
robotics); and Daniel Beßler, Robert Porzel (episodes).
Ontology Design Patterns, in: A. Barton, S. Seppälä, D. Porello (Eds.), Proceedings of the
Joint Ontology Workshops 2017, CEUR-WS.org, 2019.
[10] T. Mossakowski, C. Maeder, K. Lüttich, The Heterogeneous Tool Set, Hets, in: O. Grumberg,
M. Huth (Eds.), TACAS 2007, volume 4424 of LNCS, Springer, 2007, pp. 519–522.
      </p>
    </sec>
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