1. Controlled Pendulum Case Study

This case study follows a controlled pendulum through progressively richer simulation models. It demonstrates how SysSimX combines heterogeneous components, co-simulation, hybrid events, algebraic loops, and runtime model switching.

1.1. System at a Glance

The example closes the loop from a reference angle through a sensor and controller to a pendulum plant:

Controlled pendulum system

• Reference: SineAngleTrajectory generates the target angle.

• Feedback: AnglePotentiometerADC and AnglePotentiometerDecoder measure and reconstruct the angle.

• Control: PIDContinuous computes the drive command.

• Plant: drive and pendulum components produce the motion, including contact behavior.

• Model fidelity: FMU, OpenSim, and FEM variants can be combined or selected at runtime.

1.2. Notebook Roadmap

• Baseline system model - closed-loop FMU model compared with a monolithic reference.

• Quantization and sampling - measurement resolution and sampling effects.

• Algebraic loop - tightly coupled drive and pendulum dynamics.

• Rigid contact - event synchronization and step-size convergence.

• Multi-model switching - FMU/OpenSim/FEM model changes near contact.

Start with the baseline notebook, then follow the sequence to see how each added capability changes the simulation.

1.3. Related Documentation

The Concepts page explains the framework mechanisms used throughout this case study. For implementation details, see the component API and master algorithm API.