Control, Estimation, and Cyber-Physical Systems
Feedback, Observability, and Robustness
Core Control Ideas
Control engineering studies how to influence system behavior through feedback. In state-space form, and . The central questions are stabilizability, observability, robustness, and performance under uncertainty.
Essential Terms
Which property determines whether the internal state can be reconstructed from output measurements?
Observability is the standard property governing state reconstruction from outputs.
Correct answer: Observability
Why is robustness a central concern in engineering control?
Controllers must perform reliably despite uncertainty and changing operating conditions.
Correct answer: Because real systems deviate from ideal models and experience disturbances, delays, and noise.
Cyber-Physical Risk
As engineered systems become networked and software-defined, vulnerabilities in sensing, communication, and actuation can become safety-critical.
Classical vs. Modern Control
Classical control
- Frequency-domain methods
- Strong intuition for SISO systems
Modern control
- State-space representation
- Scales better to MIMO and optimal design
Which estimator is most associated with linear systems under Gaussian noise?
The Kalman filter is the optimal linear recursive estimator under those assumptions.
Correct answer: Kalman filter
What is one key feature of a cyber-physical system?
Cyber-physical systems couple software and hardware with real-world dynamics.
Correct answer: It tightly integrates computation, networking, sensing, and physical processes.