# Chapter nine

Tutorial sheets

## Chapter three: Introduction to Feedback

These tutorials are on the theme of linear feedback control, for example with G(s) representing a system, M(s) a compensator and d an input disturbance signal:

Core skills are things such as:

Why would I create such a feedback loop?

How do such closed-loop system behave?

Are there generic analysis tools for assessing the behaviour?

Are there generic design tools for ensuring the behaviour meets specifications?

The tutorials are a combination of PDF files, with brief worked solutions and video talk through tutorials showing detailed problem solving procedures.

### Feedback concepts and introduction

Defining closed-loop transfer functions and links between compensator parameters and closed-loop behaviour.

### Feedback concepts and introduction

Video tutorials with worked solutions to reinforce concepts from tutorials above.

### Closed-gain and offset

Several of the gain questions overlaps with the similar section in modelling.

Introductory questions on gain and offset (PDF, 627KB)

Offset and advanced scenarios (PDF, 595KB)

### Closed-gain and offset

Video tutorials with worked solutions to reinforce concepts from tutorials above.

### Block diagrams

Students should handle small variations on how blocks/signals are connected in a feedback loop.

Simple block diagram questions (PDF, 632KB)

### Heuristic PI design

Videos giving some worked examples in a tutorial fashion of PI analysis and design.

Video comparing different PI designs – first order examples.

Video comparing different PI designs – second order examples.

Video on iterative design – Note: there is a minor typo in cruise control closed loop model – should be 0.5/(s+0.5).

### Longer questions

More representative of exam style questions with multi-step requirements and re-emphasising the potential of MATLAB for checking work and incorporating PI design.

Exam style questions (PDF, 712KB)

Use of MATLAB (PDF, 405KB)