  In Industry 4.0, Cyber-Physical Systems (CPS) generate vast data sets that
can be leveraged by Artificial Intelligence (AI) for applications including
predictive maintenance and production planning. However, despite the
demonstrated potential of AI, its widespread adoption in sectors like
manufacturing remains limited. Our comprehensive review of recent literature,
including standards and reports, pinpoints key challenges: system integration,
data-related issues, managing workforce-related concerns and ensuring
trustworthy AI. A quantitative analysis highlights particular challenges and
topics that are important for practitioners but still need to be sufficiently
investigated by academics. The paper briefly discusses existing solutions to
these challenges and proposes avenues for future research. We hope that this
survey serves as a resource for practitioners evaluating the cost-benefit
implications of AI in CPS and for researchers aiming to address these urgent
challenges.
