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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Barriers and challenges for AI and HRC integration</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Josep Rueda</string-name>
          <email>jrueda@ikerlan.es</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Gorka Sorrosal</string-name>
          <email>gsorrosal@ikerlan.es</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Gerardo Minella</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Tomasz Kołcon</string-name>
          <email>tomasz.kolcon@piap.lukasiewicz.gov.pl</email>
          <xref ref-type="aff" rid="aff5">5</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Perin Ünal</string-name>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Panagiotis Vlacheas</string-name>
          <xref ref-type="aff" rid="aff4">4</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sharath Chandra Akkaladevi</string-name>
          <email>Sharath.Akkaladevi@profactor.at</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Ikerlan Technology Research Centre, Basque Research and Technology Alliance, BRTA</institution>
          ,
          <addr-line>Po J.M. Arizmendiarrieta, 2, 20500, Arrasate/Mondragón, Gipuzkoa</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Instituto Tecnológico de Informática</institution>
          ,
          <addr-line>Camino de Vera S/N, Valencia, 46022</addr-line>
          ,
          <country country="ES">Spain</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>PROFACTOR GmbH</institution>
          ,
          <addr-line>Im Stadtgut D1, Steyr-Gleink, 4400</addr-line>
          <country country="AT">Austria</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Teknopar Industrial Automation</institution>
          ,
          <addr-line>1471. Cad.. No: 3-5, 06370 Yenimahalle/Ankara</addr-line>
          ,
          <country country="TR">Türkiye</country>
        </aff>
        <aff id="aff4">
          <label>4</label>
          <institution>WINGS ICT Solutions</institution>
          ,
          <addr-line>189, Siggrou Avenue, 17121 Athens</addr-line>
          ,
          <country country="GR">Greece</country>
        </aff>
        <aff id="aff5">
          <label>5</label>
          <institution>ukasiewicz Research Network - Industrial Research Institute for Automation and Measurements PIAP</institution>
          ,
          <addr-line>Al. Jerozolimskie 202, 02-486 Warsaw</addr-line>
          ,
          <country country="PL">Poland</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The flexibility provided by collaborative robotics is making it increasingly relevant in industrial scenarios. However, this growth is also highlighting the existing limitations and integration challenges of both collaborative robotics and the AI that supports many of its applications. This paper outlines the main challenges identified that hinder the integration of Human-Robot Collaboration at different levels of interaction: physical contact management, object handling, environment avoidance, task scheduling and management and task scheduling adaptation. These challenges have been focused and analyzed from the perspective of the specific use cases of the AI-PRISM project.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;HRC</kwd>
        <kwd>Challenges</kwd>
        <kwd>AI-PRISM</kwd>
        <kwd>Artificial Intelligence1</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Modern industry, with its trend towards smaller and more customized production batches,
necessitates increased flexibility and adaptability [1; 2]. Traditional industry struggles to adapt to
unforeseen situations or production changes [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], while full automation remains costly and complex
[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. The combination of robots for precision and repeatability with human workers for flexibility in
shared tasks offers a cost-effective solution [5; 6], often utilizing collaborative robots (cobots) to
ensure operator safety [7; 8].
      </p>
      <p>
        However, ensuring human safety in enclosure-free shared workspaces requires effective
humanrobot interaction (HRI) techniques [7; 8]. HRI techniques aim to facilitate safe interactions between
robots and human workers in collaborative scenarios. These interactions are categorized into four
levels based on the degree of human-robot interaction [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]:
• Task design level: It corresponds to safety and the human-robot interaction itself during the
execution of tasks in different degrees of automation.
• Operation level: Focuses on the actions executed by the robot and aspects related to its
environment such as obstacle avoidance and smooth workflow between human and robots. • Work
cell level: Focuses on the coordination of tasks to optimize sub-processes and reduce risk situations
by optimal planning of tasks and sub-processes.
• Process level: finally, the management of sub-processes to ensure the production objectives are
performed at the process level.
      </p>
      <p>
        Addressing various aspects of human-robot interaction within collaborative applications presents
challenges crucial for ensuring safety, efficiency, and productivity. These challenges include
managing physical contact, handling objects, navigating environments, and task scheduling and
adaptation [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
      </p>
      <p>Effective management of physical contact is
essential for ensuring the safety of human
operators in shared environments,
encompassing both expected interactions (e.g.,
teaching or hand-guiding applications) and
unexpected collisions. Effective management of
physical contact is essential for ensuring the
safety of human operators in shared
environments, encompassing both expected
interactions (e.g., teaching or hand-guiding
applications) and unexpected collisions. .</p>
      <p>Improper object handling poses risks to
human workers, necessitating the ability to
handle objects in the workspace, especially
deformable or complex items. Avoiding contact
entirely is sometimes necessary for process
efficiency or safety, highlighting the critical need
for evasion capabilities when navigating in
shared environments to prevent safety stops or blockages.</p>
      <p>Finally, at the work-cell level, task scheduling, management, and adaptation are pivotal for
collaborative processes. Optimizing task scheduling in shared environments is crucial for productivity
and operator safety, minimizing potential risks and collisions. Additionally, adapting production and
planning to unforeseen changes is vital for maintaining process quality amidst disruptions, such as
process or machine failures.</p>
      <p>Next, the paper proceeds to present AI-PRISM project use cases, focusing the identified challenges
and solutions into the selected industrial use cases.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Main Challenges and Barriers in Use cases</title>
      <p>This section delves into the main challenges and barriers confronted by the current industrial
framework that would encourage the deployment of human-robot collaborative solutions. These
industrial barriers are tackled by the AI-PRISM project, which represents a comprehensive research
initiative with the goal of providing adaptable AI-based solutions for the manufacturing industry.
The project addresses challenges in unpredictable manufacturing scenarios, emphasizing flexible and
collaborative environments with human-robot interaction and integrates human-centered AI
concepts with the objective to overcome adoption barriers. Said solution encompasses a robotic
platform designed to streamline the automation of challenging tasks, creating a human-robot
cooperative environment. This includes an AI-monitored robot human relationship to prevent unsafe
situations and the necessary infrastructure for seamless integration.</p>
      <p>Five use cases within AI-PRISM, have been selected for the integration of collaborative scenarios
addressing the physical and psychological fatigue of the operator. In furniture manufacturing,
automation faces challenges due to the complexity and quality standards of tasks such as preparation,
painting, and finishing wooden parts. The electronics use case focuses on precise automatic
positioning of components to reduce human stress. In food and beverages, scenarios include handling
hazardous materials, sorting bottles, applying stickers, managing broken glass, and packaging custom
orders. Product assembly entails testing appliances and final packaging. Discrete manufacturing
involves visualizing and recognizing PCBs, testing them, and transporting them. These use cases
emphasize the existing diversity of challenges (see Table 1) across the industrial framework to deploy
safe human-robot collaborative solutions.</p>
      <p>Following, each use case is thoroughly elucidated, providing a process overview and a step by-step
breakdown. Additionally, the narrative details the roles of both the robotic assistant and the human
operator, emphasizing their collaboration in addressing their specific challenges.</p>
      <sec id="sec-2-1">
        <title>2.1. Furniture Use Case</title>
        <p>This case studies the painting process of a factory of small furniture. Our goal is to enhance its
painting process to cope with increased production
demands. Figure 2 shows operations involved in
painting process.</p>
        <p>The first challenge lies in the reliance on skilled
workers for painting tasks by integrating
collaborative robots (cobots). These robots will share
duties with skilled workers, allowing the latter to
move to other tasks if needed.</p>
        <p>To enhance production efficiency, an AI-based
application will be developed to optimize task scheduling and scheduling adaptation at work cell level.
This application will oversee the plant resource management, including human workers, robot
training planification and schedule adaptation when unforeseen events occur.</p>
        <p>A cobot will be introduced in the paining cell in charge of the finishing operation. This cobot will
be trained in a training cell, by a skilled worker. Once the cobot is trained it can replace the painter
when needed or assist this same worker in painting tasks. The cobot will provide security measures
to avoid contact with the worker. In case the worker gets close to the collaborative robot it will reduce
velocity and stop before contact.</p>
        <p>The introduction of collaborative robots requires adjustments in production planning and
scheduling. This includes accommodating new tasks, training robots for new products, and
integrating robot training into production planning.</p>
        <p>To address these challenges, a standardized data model based on the ISA95 standard will facilitate
clearer communication of information among different services, data sources, and third party
software. Data transformation and validation services will ensure seamless integration with the
standardized model, promoting interoperability across different environments.</p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2. Electronics Use Case</title>
        <p>
          This case studies the precise positioning process of chips at VIGO Photonics, a European
manufacturer of semiconducting materials and instruments for photonic and microelectronic,
specialized in LWIR and MWIR detectors and modules. The manufacturing process is largely
based on manual activities and the operator's experience. So far, the most challenging and time
consuming moment is finding the center of the chip - specifically, the center of the physical structure
of the semiconductor layers. The process currently is done manually by the operator by turning knobs
on a mechanical XY stage and the following problems were identified: high degree
of production rejects, long procedure time, and long-term concentration by the operator [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ]. A
robotic arm is replaced by a precise XY stage and a microscope camera. The use of such a set is
necessary due to the size of semiconductor structures, which
usually have dimensions of micrometers.
        </p>
        <p>For this process, several stages take place: station
calibration, inserting the chip, finding the structure center,
and stick (wire) insertion and gluing.</p>
        <p>Due to short production runs and not always having
precisely defined features, AI will be used to find the center
of the chip. The positioning of the motorized table is
performed automatically by a driver equipped with AI-based
algorithm. Additionally, it will be possible to detect
manufacturing defects in semiconductors.</p>
        <p>In this case, human robot collaboration is unique
because it is on a micro scale. This involves relieving the
operator of the most stressful and time-consuming tasks,
especially since full automation of the cycle in this scenario has no economic or practical
justification..</p>
      </sec>
      <sec id="sec-2-3">
        <title>2.3. Food and Beverages Use Case</title>
        <sec id="sec-2-3-1">
          <title>In the Food and Beverages sector, three use cases are</title>
          <p>considered in Athenian Brewery premises.</p>
          <p>Filtration Preparation Process: This process involves
heavy tasks and handling hazardous chemical compounds
delivered in powder form. To enhance safety and human-robot
collaboration, a collaborative robot (cobot) is integrated into the
operational area. The cobot assists in transporting sacks onto the
conveyor belt while the human operator monitors the
environment and intervenes when necessary. This integration optimizes task allocation, ensuring
efficient and safe filtration preparation.</p>
          <p>Return Bottle Sorting: The brewery implements a large automation system to sort return
bottles from the market. A robotic manipulator depalletizes
crates, and trained personnel categorize the bottles based on their
type. Safety considerations are paramount due to the delicate
nature of glass bottles. To ease the workload of human workers
and enhance sorting accuracy, a cobot equipped with a machine
vision system is introduced. This cobot aids in the bottle sorting
process, contributing to a more organized and efficient
operation.</p>
        </sec>
      </sec>
      <sec id="sec-2-4">
        <title>2.4. Consumer Electronics Assembly Use Case</title>
        <sec id="sec-2-4-1">
          <title>The Silverline use case involves demonstrating</title>
          <p>the integration of the Robot Operating System (ROS)
into industrial settings, focusing on safety, efficiency,
and optimization. This integration is analyzed across
four levels of HRI: Task Design, Operation, Work Cell,
and Process.</p>
          <p>At the Task Design Level, we aimed to ensure safe collaboration between robots and humans,
considering safety protocols and interaction mechanisms for efficient task execution. This involved
orchestrating robot actions, including navigation and workflow integration with human workers, to
ensure effectiveness. At the Work Cell Level, optimization of task coordination was prioritized,
involving planning and scheduling to enhance subprocess efficiency. Furthermore, at the Process
Level, effective management of subprocesses was implemented to align with production objectives,
ensuring coordination between robotic and human
activities for maximum productivity.</p>
          <p>Overall, the integration addresses safety, efficiency, and
optimization, providing valuable insights into ROS
integration's practical aspects. These insights contribute
to the broader field of HRI in industrial applications.</p>
          <p>The challenges encountered and solutions devised in this
project highlight the importance of ROS integration for
enhancing industrial processes and ensuring
collaboration between humans and robots. This
approach underscores the significance of ROS in driving
productivity and goal attainment in industrial environments, ultimately contributing to advancements
in HRI.</p>
        </sec>
      </sec>
      <sec id="sec-2-5">
        <title>2.5. Discrete Manufacturing Use Case</title>
        <p>The use case targets the integration of
collaborative robots to aid in the production and
testing of Printed Circuit Boards (PCBs), aiming
to address challenges associated with manual
handling and testing tasks. Human operators
currently perform these tasks, which involve
loading PCBs into testing fixtures and
configuring work cells for different PCB types,
leading to issues like repetitive tasks and
potential mental fatigue. AI-PRISM proposes
introducing collaborative robots into the process
to alleviate these challenges.</p>
        <p>Two scenarios are envisioned for human-robot collaboration: the first involves a static robotic
manipulator handling and testing PCBs, aiming to reduce strain on human operators and ensure
consistent and precise testing. The second focuses on configuring work cells for new PCB types, where
a mobile robot assists humans by carrying necessary parts and facilitating assembly. Additionally,
easy-to-use interfaces enable non-expert users to configure robotic tasks quickly.
Challenges and barriers are categorized into four levels of interaction: task design, operation, work
cell, and process. These include minimizing strain on operators, optimizing robot actions and
navigation, coordinating tasks within work cells, and managing sub-processes to meet production
objectives. Overcoming these challenges is crucial for the successful integration of collaborative robots
into the PCB production and testing process, improving efficiency and reducing human strain.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Conclusions</title>
      <p>The integration of artificial intelligence (AI) and human-robot collaboration (HRC) introduces a
spectrum of challenges and barriers that demand careful consideration. Throughout the exploration
of the challenges embedded in these use cases we can highlight the difference in nature that exists
between said challenges, ranging between very different industrial scenarios and tasks, empathizing
the necessity of successfully integrating of human-robot collaborative solutions, ensuring not only
the safety and efficiency of operations but also the required adaptability for unpredictable
manufacturing scenarios. This adaptability would be implemented by a user-friendly approach which
would allow individuals without expertise in robotics to effectively 'program' robots for complex and
demanding tasks. Stated so, AI-PRISM would help to address and overcome the barriers and
challenges due to the simplicity practicality of the solution.</p>
    </sec>
    <sec id="sec-4">
      <title>Acknowledgements</title>
      <p>This work and AI-PRISM project has been supported by the European Union’s Horizon Europe
research and innovation program under grant agreement No 101058589.</p>
    </sec>
    <sec id="sec-5">
      <title>Declaration on Generative AI</title>
      <sec id="sec-5-1">
        <title>The author(s) have not employed any Generative AI tools.</title>
      </sec>
    </sec>
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        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>