TABLE OF CONTENTS 
| Rule | K c | T i | T d | Comment |
|---|---|---|---|---|
| Ultimate cycle | ||||
| Ziegler and Nichols (1942). | [0.6K u, K u] | 0.5T u | 0.125T u | Quarter decay ratio |
| Farrington (1950). | [0.33K u, 0.5K u] | T u | [0.1T u, 0.25T u | |
| McAvoy and Johnson (1967). | 0.54K u | T u | 0.2T u | |
| Atkinson and Davey (1968). | 0.25K u | 0.75T u | 0.25T u | |
| 20% overshoot servo response | ||||
| Carr (1986); Pettit and Carr (1987). | K u | 0.5T u | 0.125T u | Underdamped |
| 0.6667K u | T u | 0.167T u | Critically damped | |
| 0.5K u | 1.5T u | 0.167T u | Overdamped | |
| Parr (1989) pages 190, 191, 193. | 0.5K u | T u | 0.2T u | ??0.45 |
| 0.5K u | T u | 0.25T u | ||
| 0.5K u | 0.34T u | 0.08T u | ||
| Tinham (1989). | 0.4444K u | 0.6T u | 0.19T u | Less than quarter decay ratio response |
| Blickley (1990). | 0.5K u | T u | [0.125T u, 0.167T u] | Quarter decay ratio |
| Corripio (1990) page 27. | 0.75K u | 0.63T u | 0.1T u | Quarter decay ratio |
| str m (1982). | K u cos | [1]T i (373) | ?T i (373) | |
| Representative results | ||||
| 0.87K u | 0.55T u | 0.14T u | | |
| 0.71K u | 0.77T u | 0.19T u | | |
| 0.50K u | 1.19T u | 0.30T u | | |
| str m and H gglund (1984). | | arbitrary | | Specify A m |
| K u cos | ?T d (374) | [2]T d (374) | Specify | |
| Hang and str m (1988b). | K u |
