This page contains information about version 3.1.5 of *Feedback Systems* by Karl J. Åström and Richard M. Murray. Version 3.1.5j is a preprint copy of the second edition of the text, which has been sent to the publisher for creation of final figures.

Additional info and links:

- Revision date: 24 July 2020
- Complete book - this a PDF of the entire book, as a single PDF file (573 pages, 35 MB).
- Individual chapters: P, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, B

The electronic edition of *Feedback Systems* is provided with the permission of the publisher, Princeton University Press. This manuscript is for personal use only and may not be reproduced, in whole or in part, without written consent from the publisher.

## Errata

A full list of errata including page and line numbers is maintained on the errata page.

Errata for this version only:

Page | Line | Description | Status |
---|

1-23 | 25 | In Section 1.8, breaking should be braking | Closed |

1-23 | 7 | In Section 1.7, there is a typo/missing word near the end of the section | Closed |

1-23 | 7 | In the air-fuel example in Section 1.8, missing reference to Figure 1.16b | Closed |

1-25 | 8 | In the paper mill description in Section 1.8, "production unit" should be "production units" | Closed |

1-25 | 8 | In Section 1.8 text on paper mills, "production unit" should be "production units" | Closed |

10-15 | | In Section 10.3, the caption for Figure 10.11 seems to have a typo | Closed |

10-18 | | In Section 10.4, the Figure 10.14 caption has a grammatical error | Closed |

10-18 | | In Section 10.4, Figure 10.14(b) seems to missing the curve for reverse driving phase | Closed |

10-2 | -8 | In Section 10.1, there is a typo in the oscillation condition equation | Closed |

10-2 | -8 | In Equation 10.1, there's a typo 0 instead of ')' | Duplicate |

10-3 | -7 | In Section 10.1, the word "circuit" is misspelled. | Closed |

10-7 | | In Section 10.2, part of Figure 10.5 seems to be missing | Closed |

11-12 | 8 | Ziegler-Nichols tuning rules don't quite match the original gains from the Ziegler-Nichols paper | Closed |

11-13 | 22, 23 | Original Ziegler-Nichols gains listed after improved tuning rules are incorrect | Closed |

11-13 | 22, 23 | Updated tuning rules are incorrect in equation (11.10b) | Closed |

11-16 | | In Section 11.4, the Figure 11.10 caption has a typo | Closed |

11-5 | 19 | In Section 11.1, the word "frequencies" is duplicated | Closed |

12-10 | 1 | In Section 12.2, there is a singular vs. plural error when talking about the control signal | Closed |

12-10 | -1 | In Section 12.2, there is a typo in the equation for P^+(s) | Closed |

12-11 | -4 | In Section 12.2, the word "inherently" is misspelled | Closed |

12-11 | -4 | In Section 12.2, the sentence about sensitivity to model uncertainty has a grammatical issue | Closed |

12-11 | 2 | In Section 12.2, there is a typo in the equation for the approximate inverse of P(s) | Closed |

12-14 | -5 | In Section 12.3, there is a missing space | Closed |

12-16 | 11 | In Section 12.4, the word "limitations" is misspelled | Closed |

12-28 | | In Section 12.6, there is a missing comma in the caption of Figure 12.17 | Closed |

12-3 | -14 | In Section 12.1, the additional transfer functions for the F != 1 case seem to be incorrect | Closed |

12-30 | 18 | In Section 12.6, a sentence in Theorem 12.2 is grammatically incorrect | Closed |

12-35 | 4 | In Section 12.7, there's a typo in the discussion of inner/outer loop design | Closed |

12-35 | 11 | In Section 12.7, there's a grammatical error where it talks about the closed loop system H i | Closed |

12-4 | -5 | In Section 12.1, the vector w corresponding to Fig. 12.1 seems to be incorrect | Closed |

12-5 | -3 | In Section 12.2, the word "desired" is misspelled | Closed |

12-5 | | In Section 12.2, the feedforward command u fv is mislabeled in Figure 12.3 | Closed |

12-6 | 17 | In Section 12.2, the condition for Gyv being small seems to be misstated | Closed |

13-15 | 10 | In Section 13.3, the word "response" is duplicated | Closed |

13-6 | -11 | In Section 13.2, the word "when" is incorrectly capitalized | Closed |

13-7 | 9 | In Section 13.2, the word "transfer" is misspelled | Closed |

13-7 | 9 | In Section 13.2, the word "point" is duplicated | Closed |

13-7 | 8 | In Section 13.2, there's a grammatical issue in the discussion of system stability | Closed |

13-8 | -9 | In Example 13.6 (Vinnicombe metric), the formula for conjugate point is missing a minus sign | Closed |

2-11 | 19 | In discussion on PI control in Section 2.2, incorrect formula for G yv when \omega is small | Closed |

2-2 | 37 | In Section 2.1, there is a typo in the discussion of solving for an exponential input | Closed |

2-4 | 9 | In Section 2.1, referred is misspelled | Closed |

2-5 | 5 | In Example 6.8, signalsith should be signals with | Closed |

2-7 | 9 | Equation 2.11 is not equal to the preceding expression from which it came | Closed |

2-7 | -12 | Equation (2.11) has the wrong formula for the transfer function | Duplicate |

2-8 | 12 | In Section 2.2, one too many parentheses in an expression for y(t) | Closed |

2-8 | 15 | Display equation above equation (2.12) has extra set of parentheses | Closed |

2-9 | 13 | In discussion of proportional control in Section 2.2, missing v 0 in displayed equation | Closed |

3-10 | 33 | In Section 3.1, there is a typo for plurality | Closed |

3-10 | -8 | In discussion on algebraic loops in Section 3.2, there is an extra "be" | Closed |

"3.1.5" is not in the list of possible values (2.11c, 3.0h, 3.0i, 3.0j) for this property.