  This paper explores the opportunities of using a digital twin to address the
complexities of collaborative production systems through an industrial case and
a demonstrator. A digital twin, as a virtual counterpart of a physical
human-robot assembly system, is built as a front-runner for validation and
control through design, build, and operation. The forms of digital twins along
the system life cycle, the building blocks, and potential advantages are
presented. Recommendations for future research and practice in the use of
digital twins in the field of collaborative robots are given.
