=Paper= {{Paper |id=Vol-2687/paper9 |storemode=property |title=Pepper4Museum: Towards a Human-like Museum Guide |pdfUrl=https://ceur-ws.org/Vol-2687/paper9.pdf |volume=Vol-2687 |authors=Giovanna Castellano,Berardina De Carolis,Nicola Macchiarulo,Gennaro Vessio |dblpUrl=https://dblp.org/rec/conf/avi/CastellanoCMV20 }} ==Pepper4Museum: Towards a Human-like Museum Guide== https://ceur-ws.org/Vol-2687/paper9.pdf
           Pepper4Museum: Towards a Human-like Museum Guide
                           Giovanna Castellano                                                           Berardina De Carolis
                     Department of Computer Science                                                 Department of Computer Science
                      University of Bari Aldo Moro                                                   University of Bari Aldo Moro
                               Bari, Italy                                                                     Bari, Italy
                      giovanna.castellano@uniba.it                                                    berardina.decarolis@uniba.it

                            Nicola Macchiarulo                                                               Gennaro Vessio
                     Department of Computer Science                                                 Department of Computer Science
                      University of Bari Aldo Moro                                                   University of Bari Aldo Moro
                                Bari, Italy                                                                   Bari, Italy
                       nicola.macchiarulo@uniba.it                                                     gennaro.vessio@uniba.it

ABSTRACT                                                                               to a wider population [13]. One of the most promising ICT applica-
With the recent advances in technology, new ways to engage vis-                        tions in this domain concerns the provision of personalized services,
itors in a museum have been proposed. Relevant examples range                          in which the visitor’s specific characteristics and preferences are
from the simple use of mobile apps and interactive displays to vir-                    taken into account [5], and recommendation of personalized mu-
tual and augmented reality settings. Recently social robots have                       seum visiting paths [18]. Monitoring what visitors are looking at,
been used as a solution to engage visitors in museum tours, due to                     what they like or dislike, etc., can be used to personalize and en-
their ability to interact with humans naturally and familiarly. In                     hance their experience during the visit [31]. Successful applications
this paper, we present our preliminary work on the use of a social                     range from the simple use of mobile apps and interactive displays
robot, Pepper in this case, as an innovative approach to engaging                      to virtual and augmented reality settings.
people during museum visiting tours. To this aim, we endowed                              For instance, in [3] an indoor location-aware architecture, which
Pepper with a vision module that allows it to perceive the visitor                     relies on a wearable device to automatically provide the user with
and the artwork he is looking at, as well as estimating his age and                    cultural content related to the observed artwork, is proposed. A
gender. These data are used to provide the visitor with recommenda-                    similar approach was followed in [34], where Zhang et al. proposed
tions about artworks the user might like to see during the visit. We                   the use of a wearable camera equipped with image processing
tested the proposed approach in our research lab and preliminary                       capabilities to solve the task of artwork identification within a mu-
experiments show its feasibility.                                                      seum. A remarkable contribution to the topic of personalized visit
                                                                                       experience was provided in [5], where Bartolini et al. proposed
CCS CONCEPTS                                                                           a context-aware recommendation system aimed at supporting in-
                                                                                       telligent multimedia services for the users. In [1] and [16], the
• Computing methodologies → Visual content-based index-
                                                                                       authors explored the possibility to harness electroencephalograph
ing and retrieval; • Applied computing → Fine arts; • Human-
                                                                                       (EEG) signals captured by off-the-shelf EEG low-cost headsets to
centered computing → Interactive systems and tools.
                                                                                       understand if an artwork is of interest for a visitor. More recently,
                                                                                       Cardoso et al. [7] proposed the use of a mobile application to set
KEYWORDS
                                                                                       museum itineraries where visitors can move at their own pace and,
Museum visit; Human-Robot Interaction; Computer Vision.                                at the same time, have all the complementary information they
ACM Reference Format:                                                                  need about points of interest adapted to the user’s needs.
Giovanna Castellano, Berardina De Carolis, Nicola Macchiarulo, and Gen-                   A recent solution to engage visitors in museum tours is to use
naro Vessio. 2020. Pepper4Museum: Towards a Human-like Museum Guide.                   social robots. Social robots are embodied, autonomous agents that
In Proceedings of 𝐴𝑉 𝐼 2𝐶𝐻 2020: Workshop on Advanced Visual Interfaces                communicate and interact with humans on a social and emotional
and Interactions in Cultural Heritage (𝐴𝑉 𝐼 2𝐶𝐻 2020). ACM, New York, NY,              level. They represent an emerging field of research focused on de-
USA, 5 pages.                                                                          veloping a “social intelligence” that aims to maintain the illusion
                                                                                       of dealing with a human being [4]. Thanks to their ability to inter-
1    INTRODUCTION                                                                      act with humans in a natural and familiar way, social robots are
In the last few years, due to technology improvements and drasti-                      spreading more and more often into human life not only for enter-
cally declining costs, many innovative Information and Communi-                        tainment, but also to assist users in their activities of daily living, or
cation Technology (ICT) solutions have been applied to the cultural                    in teaching and educational settings. In particular, they can provide
domain, with the aim of making art more accessible and engaging                        novel, interactive social interfaces in cultural and tourism services
                                                                                       [33], thus improving the overall experience of the user [28].
                                                                                          Historical examples of museum tour guide robots include RHINO
𝐴𝑉 𝐼 2𝐶𝐻 2020, September 29, Island of Ischia, Italy
© Copyright 2020 for this paper by its authors. Use permitted under Creative Commons
                                                                                       [6] and Minerva [32]. RHINO integrates low-level probabilistic rea-
License Attribution 4.0 International (CC BY 4.0).                                     soning and high-level problem solving, embedded in first order
𝐴𝑉 𝐼 2𝐶𝐻 2020, September 29, Island of Ischia, Italy                                                                     Giovanna Castellano et al.


                                                                          following, the main modules we are developing for museum visit
                                                                          assistance are briefly described.

                                                                          2.1    Museum Mapping and Localization
                                                                          Simultaneous Localization And Mapping (SLAM) is the problem
                                                                          of constructing and updating a map of an unknown environment
                                                                          while keeping track of the robot’s location within it. As building
                                                                          maps is one of the fundamental tasks of mobile robots, a lot of
                                                                          researchers focused on this problem. The SLAM algorithms mainly
                                                                          use optical sensor data to reconstruct the map of the environment
                                                                          and determine the orientation and position of the robot. There are
         Figure 1: Overview of the system components.
                                                                          two common approaches to SLAM: Visual SLAM, based on data
                                                                          captured from RGB or RGB-D cameras, and LiDAR (Light Detection
logic, to navigate at high speeds through dense crowds, while re-         and Ranging) SLAM, based on data captured from laser sensors.
liably avoiding collisions with obstacles. Differently from RHINO,        The approach based on LiDAR is typically faster and more accurate
Minerva learns the map from sensor data and presents an improved          than Visual SLAM [15]. As far as concerns the Pepper’s capabilities
interaction system with the users. To do this, it adopts a “pervasively   of mapping and navigating in an environment, Pepper is able, using
probabilistic” approach, which relies on explicit representations         the NaoQI API, to: i) map the environment; and ii) localize itself and
of uncertainty in perception and control. More recently, in [17],         navigate inside the mapped environment in accordance with the
Germak et al. developed a telepresence robot designed as a tool to        SLAM approach. To this aim, Pepper uses its odometry and laser
explore inaccessible areas of a cultural site. In [2] the humanoid        sensors. Thus, as a first step, we developed a module that allows
robot Pepper has been used as a tour guide in a museum. Pepper            Pepper to map the museum space moving around autonomously.
was equipped with several modules, useful for accompanying visi-          Then, once the mapping has been completed, the resulting map is
tors and interacting with them. Suddrey et al. [30] recently showed       stored as a 2D image (see Fig. 2a). Successively, the map is anno-
that the Pepper’s basic functionalities can be improved to enable         tated with the points of interest close to the artworks’ position and
the robot to provide autonomous and interactive tours.                    each point is tagged with the artwork ID. This ID is then used to
   In this context, the recent advances in Computer Vision are            retrieve information about the corresponding artwork (i.e., author,
allowing researchers to endow robots with novel and powerful              description, image, tags).
capabilities. In this paper, we present our preliminary work on the          Besides annotating the points of interest in the space, Pepper
use of a social robot, Pepper in this case, as a museum tour guide.       has to detect and localize visitors in the mapped space. This is
In particular, we present a vision-based approach for supporting          done with the use of a particular deep neural network for object
people during a museum visit. The vision module allows Pepper             detection. Specifically, we used SSD MobileNetV2 [27], a state-of-
to perceive the presence of a visitor and localize him in the space,      the-art deep learning model pre-trained on the MS COCO dataset
and estimating his age and gender. Moreover, a visual link retrieval      [22], which is able to detect 80 different objects, including people.
module gives Pepper the ability to take the image of the painting         Given the frames captured by the Pepper’s camera as an input,
observed by the visitor as a visual query to search for visually          SSD MobileNetV2 returns a bounding box around all the detected
similar paintings in the museum database. The robot uses these            people, as shown in Fig. 2b.
data and other information acquired during the dialog to provide             We fused the information about the bounding box of a person
the visitor with recommendations about similar artworks he might          in the image with the data captured from the depth camera of the
like to see in the museum. We tested the proposed approach in our         robot in order to compute the coordinates of the visitor in the map
research lab and preliminary experiments show its feasibility.            previously created with the SLAM algorithm. To determine if a
                                                                          visitor is close to an artwork, we compute the Euclidean distance
2    PEPPER4MUSEUM                                                        between the person’s point and each point of the artwork. If the
                                                                          distance is less than a threshold, Pepper approaches the visitor.
Designing the behaviors of a social robot acting as a museum guide
requires endowing it with different capabilities that would provide
visitors with an engaging and effective experience during the visit.      2.2    Age and Gender Estimation
These capabilities are meant to allow the robot to detect and localize    In order to start gathering information about the target user, a
people in the museum, recognize artworks the visitor is looking at,       soft biometric module is used [11]. The soft biometric module al-
profile the user during the visit so as to generate suitable recommen-    lows Pepper to automatically infer the age and gender of the user
dations, and finally engage people in the interaction using suitable      who is interacting with it. The algorithm follows the approach de-
conversational skills. This is the final aim of the Pepper4Museum         scribed in [26], which relies on a fine-tuned version of the VGG16
project (Fig. 1) which exploits the combination of Computer Vision        state-of-the-art deep convolutional neural network [29], using an
and Social Robotics.                                                      unconstrained image dataset. The capability of deep neural net-
   As robot platform we use Pepper, a semi-humanoid robot de-             works to solve complex perceptual tasks has been shown in several
veloped by SoftBank Robotics. It is an omnidirectional wheeled            recent works (e.g., [9, 21]). Our approach showed a good perfor-
humanoid robot equipped with several cameras and sensors. In the          mance, as gender recognition reached an accuracy of 85%, while age
Pepper4Museum: Towards a Human-like Museum Guide                                                    𝐴𝑉 𝐼 2𝐶𝐻 2020, September 29, Island of Ischia, Italy


                                                                         in which to search for similarities among paintings [10]. These
                                                                         similarities can be used to provide semantic links among paintings
                                                                         so as to recommend artworks a visitor may be interested in.
                                                                            The proposed method is mainly based on “visual attributes” au-
                                                                         tomatically learned by a VGG16-based model. The resulting high
                                                                         dimensional representation is then embedded in a more compact
                                                                         feature space by applying Principal Component Analysis. Finally,
                                                                         similarities among paintings, i.e. visual links, are obtained through
                                                                         a distance measure in a completely unsupervised Nearest Neighbor
        (a)                         (b)                     (c)          fashion. The proposed method thus provides the nearest neighbors
                                                                         for each query image, that are those images more similarly linked
Figure 2: (a) An example of map generated after the explo-               to the input query. Relying on a completely unsupervised approach
ration of a museum space. (b) People detection. (c) An exam-             makes the proposed method simple and practical, as it excludes the
ple of interaction between a young woman and Pepper with                 necessity to acquire labels of visual links, which can be unavailable
real-time gender and age estimation.                                     or very difficult to collect.

                                                                         2.5    Behavior Manager
estimation reached an accuracy (±1 year) of 84% on the previously        A behavior is a program that combines and coordinates the ut-
mentioned dataset. Soft biometric traits can be used with two main       terances, gestures, expressions, touch-screen interactive elements,
purposes: i) improving the recommender module performance by             and locomotion based on the current robot perceptions. In the con-
filtering recommendations accordingly; and ii) adapting the robot’s      text of museum visiting, the behavior manager module can trigger
dialogue to the person it is interacting with. In our museum sce-        a particular behavior according to two approaches: reactive and
nario, we used an approach similar to the one described in [14], in      proactive.
which the robot uses a different level of formality in its dialogue,        In the reactive case, the triggered behavior is an answer to the
based on the age and gender of the person being tracked (Fig. 2c).       recognized user’s intent. In particular, user input can be provided
                                                                         via voice or through a touch screen. In the first case, the input
2.3    User Profiling and Recommender Module                             is processed by the automated speech recognition module that is
Understanding the user preferences may enable a social robot to          already encoded in the programming environment of the robot. In
adapt its behavior accordingly, hence enhancing the user satisfac-       the second case, the user can interact with the tablet of the robot,
tion during the interaction [25]. Usually this process is based on       which shows the available choices. It is worth stating that the touch
explicit feedback, e.g. specific question answering or explicit rating   screen is needed, since the overall quality of the speech recognition
of items. However, this approach, albeit more precise and reliable,      module encoded in Pepper is typically low. At the current stage of
is time consuming and requires an effort by the user.                    implementation of the system, five families of intents are captured:
    Recent trends use approaches based on implicit feedback that         greet, small_talk, current_painting information, suggestions, and tour.
can be inferred by observing and analyzing user’s behavior without       Clearly, each intent invokes a different, more or less complex, be-
interrupting the user engagement in the interaction. In the museum       havior as an answer. In the proactive case, a rule-based system, in
visit context, we decided to exploit a hybrid approach that combines     which the current state of the perception is periodically matched
observations of the user behavior with explicit questions asked by       with the preconditions of rules, has been adopted. Then, the behav-
the robot during the interaction. Then, thanks to the soft biomet-       ior associated to the selected rule is executed. If no rule is selected,
ric analysis, information about user gender and age is used as a         the robot executes the idle behavior in which it moves a bit around,
feature for triggering an initial stereotypical model for the visitor    randomly displaying on its tablet artworks present in the museum
[24]. Moreover, these data can be used to tailor the dialog and the      exhibition with the invitation to ask about them. Each behavior
information presented to the visitor (i.e., descriptions provided to a   may require the fulfillment of a service execution in the cloud of
child will be different from those provided to an adult). In addition,   Pepper4Museum as in the case of the recommendation generation.
these data, together with information about what is of interest for
the visitor (inferred by observing what the visitor is looking at and    3     PRELIMINARY STUDY
by answering to specific questions during the visit), can be used to     As a proof of concept, we preliminarly investigated the effectiveness
trigger the recommendation about what to see next in the museum.         of the different modules embedded in Pepper4Museum.
This phase represents an active process of feedback and preference          About the gender and age estimation, the soft biometric module
acquisition that allows the robot to acquire new information that        in the wild was able to recognize with 87.5% accuracy the gender of
can be used for refining subsequent recommendations.                     the visitors and with 62.5% accuracy the age of the visitors (more
                                                                         details in [8, 14]). The classification of the age was lower than we
2.4    Visual Link Retrieval                                             expected because the interaction in the wild did not guarantee a
The proposed module for link retrieval assumes that the robot has        static and frontal position of the user with respect to the camera.
knowledge about the artworks exhibited in the museum. The goal is        Also the variation of lighting conditions influenced the analysis of
to project the raw pixel images into a new, numerical feature space      the face for age estimation.
𝐴𝑉 𝐼 2𝐶𝐻 2020, September 29, Island of Ischia, Italy                                                                                Giovanna Castellano et al.


                                                                         such as colors and shapes, and conceptual elements, such as subject
                                                                         matter and meaning of the painted scene.
                                                                            The mapping and localization process could not be tested in a real
                                                                         museum due to the COVID-19 emergency. We tested this module in
                                                                         the “Museum of History of Computers” located in our department
                                                                         and we observed that its performance was overall acceptable. Some
                                                                         delay was registered when Pepper found an unexpected obstacle
                                                                         on its planned path (e.g., people crossing). The other modules need
                                                                         to be tested in the wild as soon as it will be possible.

                                                                         4    CONCLUSION AND FUTURE WORK
                                                                         In this paper, we have presented our preliminary work towards
                                                                         the development of Pepper4Museum: a human-like museum guide.
                                                                         Promising results in our research lab have been obtained. As future
                                                                         work, we plan to test and refine all the behaviors we implemented in
                                                                         this domain. Then, in order to run an experiment in a real museum
                                                                         context, a test on the integration of the described components is
Figure 3: Sample artwork queries and corresponding visu-
                                                                         needed. A test in a museum will allow for measuring the visitor
ally linked paintings provided by the system.
                                                                         experience and evaluating the impact of this technology in this
                                                                         context. Finally, it is worth remarking that the data collected by
   Then, we tested the visual link retrieval method on a database        Pepper represent a valuable source of information that can be prof-
collecting paintings of 50 very popular painters. We used data pro-      itably used to better understand and predict the visitors’ behavior
vided by the Kaggle platform,1 scraped from an art challenge Web-        [18, 19, 23]. Such an analysis could be carried out by means of graph
site.2 Artists belong to very different epochs and painting schools,     theory, e.g. [20], or process mining techniques [12].
ranging from Giotto di Bondone and Renaissance painters such as
Leonardo da Vinci and Michelangelo, to Modern Art exponents,             ACKNOWLEDGMENTS
including Pablo Picasso, Salvador Dalí, and so on. Once the reduced      Funding for this work was partially provided by Fondazione Puglia
features representing paintings were obtained, we applied the Near-      that supported the Italian project “Programmazione Avanzata di
est Neighbor matching mechanism to derive, for each query image,         Robot Sociali Intelligenti”. Gennaro Vessio acknowledges funding
the top 𝑘 matching images (𝑘 = 3 in this case). To give an illustra-     support from the Italian Ministry of Education, University and
tive example of the behavior of our system, in Fig. 3 we provide         Research through the PON AIM 1852414 project.
three sample image queries, together with the corresponding top
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