Successful collaboration with RWS

Rijkswaterstaat (RWS) will from now on use Synthesis-Based Engineering (SBE) in renovations of movable bridges and water locks to map out control requirements before they are included in tender dossiers. This should lead to more efficient collaboration with market parties that implement the control software for RWS. This decision follows several years of collaboration around SBE with TNO-ESI and the Control Systems Technology section of the Eindhoven University of Technology (TU/e). RWS made this decision after successful pilots and a market consultation.

Correct control requirements are vital

A bridge or lock is controlled by software that ensures the object operates correctly and safely. The software prevents, for example, a bridge from opening when cars are driving over it, thus preventing unsafe situations, damage, and injury. Although RWS leaves the development of control software to market parties, it is responsible for providing the control requirements that the software must meet during the tender process. These requirements must be clear, correct, complete, and consistent, even for failure situations, such as when a sensor or motor unexpectedly breaks down.

Synthesis-Based Engineering (SBE) is an advanced method that uses models to develop control software. It enables parties like RWS to efficiently achieve high-quality control software with the help of computer support.

Dennis Hendriks, a researcher at TNO-ESI, explains what SBE is: “SBE is a method that uses system models to generate control logic from control requirements. The synthesis algorithm smartly calculates all possible situations, sometimes many billions, and guarantees that the generated control logic meets the control requirements in all those situations. Subsequently, the system behavior can be validated through simulation, and the implementation can be automatically generated through code generation.”

This method saves RWS a lot of time, according to Harry Lammeretz, program manager at RWS: “The process from concept to realization takes several years. We can now involve all stakeholders in the design at an early stage. For example, we can show asset managers and operators how the object will eventually work, by using simulations and visualizations. This saves a lot of time in later stages. We can also make adjustments faster. It significantly shortens the design cycle. Furthermore, we expect less coordination with market parties that realize the implementation for us after the tender, leading to more efficient execution and lower costs.”

This decision follows years of collaboration with TU/e and TNO. Martijn Goorden, an assistant professor at TU/e, indicates: “We have looked at how RWS objects could be modeled with SBE and how to bring SBE theory into RWS practice; think for instance of the scalability of the algorithms.” Harry continues: “We have now successfully tested the method in practice through several pilots. These included, among others, renovation projects with swing bridges at Den Oever and the Stevinsluis water lock.”

In 2024, RWS organized a market consultation on applying SBE to validate control requirements. Nineteen market parties were present, and the vast majority responded positively. Based on an evaluation, RWS has now decided to apply SBE internally for all renovations of movable bridges and locks to sharpen the control requirements for tender dossiers. The developed models will also be included in the tender dossiers

In addition to the current application, RWS is also looking ahead: to applications for other objects, such as weirs and flood barriers, and exploring further automation, such as code generation. RWS will renovate a large number of objects in the coming years and believes it can work more efficiently with SBE, continuing to keep Dutch infrastructure reliable in the future.

The collaboration between RWS, TNO-ESI, and TU/e is not only interesting for these parties and the infrastructure domain. Others working with SBE can also benefit from it. For example, TNO-ESI collaborates with the Dutch high-tech industry, such as in a project with ASML and VDL-ETG. All these parties work together in the Dutch SBE ecosystem and make their results available to the entire community through the Eclipse ESCET open-source project.