  Failures in safety-critical Cyber-Physical Systems (CPS), both software and
hardware-related, can lead to severe incidents impacting physical
infrastructure or even harming humans. As a result, extensive simulations and
field tests need to be conducted, as part of the verification and validation of
system requirements, to ensure system safety. However, current simulation and
field testing practices, particularly in the domain of small Unmanned Aerial
Systems (sUAS), are ad-hoc and lack a thorough, structured testing process.
Furthermore, there is a dearth of standard processes and methodologies to
inform the design of comprehensive simulation and field tests. This gap in the
testing process leads to the deployment of sUAS applications that are: (a)
tested in simulation environments which do not adequately capture the
real-world complexity, such as environmental factors, due to a lack of tool
support; (b) not subjected to a comprehensive range of scenarios during
simulation testing to validate the system requirements, due to the absence of a
process defining the relationship between requirements and simulation tests;
and (c) not analyzed through standard safety analysis processes, because of
missing traceability between simulation testing artifacts and safety analysis
artifacts. To address these issues, we have developed an initial framework for
validating CPS, specifically focusing on sUAS and robotic applications. We
demonstrate the suitability of our framework by applying it to an example from
the sUAS domain. Our preliminary results confirm the applicability of our
framework. We conclude with a research roadmap to outline our next research
goals along with our current proposal.
