Verification and Validation of a Pressure Control Unit for Hydraulic Systems.

This paper describes the development, verification and model-based validation of a safety-critical pressure relief function for a digital hydraulic system. It demonstrates techniques to handle typical challenges that are encountered when verifying and validating cyber-physical systems with complex dynamical behaviour. The system is developed using model-based design in Simulink. The verification part focuses on verification of functional properties of the controller, where formal automated verification tools are employed. The validation part focuses on validating that the controller has the desired impact on the physical system. In the latter part search-based methods are used to find undesired behaviour in a simulation model of the system. The combination of techniques provides confidence in the resilience of the developed system.