Original article
https://www.dnvgl.com/services/hil-testing-concept-explanation--83385

Instead of being connected to the actual equipment on the vessel, the control system is connected to a HIL simulator with sophisticated models of the vessel and its equipment.

This enables systematic and comprehensive testing of control system functionality and failure handling without risk to people, equipment or environment.

Accomplished by

Facilitate systematic testing of control system:

  • design philosophy,
  • functionality,
  • performance, and
  • failure handling capability, both in normal and off-design operating conditions.

HIL simulator visualization

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subgraph HIL_Simulator {
"simulated actuators" -> "simulated sensors"
"simulated actuators" -> "simulated dynamics"
"simulated dynamics" -> "simulated sensors"
}

  +------------------------------------------------------+
  |                                                      v
+---------------------+     +--------------------+     +-------------------+
| simulated actuators | --> | simulated dynamics | --> | simulated sensors |
+---------------------+     +--------------------+     +-------------------+

Facts

  • A HIL simulator includes sophisticated mathematical models of actuators, dynamics and sensors
  • A HIL simulator constitutes a โ€œvirtual worldโ€ for the control system
  • HIL testing is performed in a safe test bed, without risk to people, equipment or environment
  • HIL testing is black-box testing
  • No source code is revealed or exposed through HIL testing
  • HIL testing is the de facto industry standard for control system software in the automotive and aerospace industries
  • Every vessel is unique regarding equipment and configuration, increasing the potential for errors