From b0a296477e24b252fa353f123d559513848a35c9 Mon Sep 17 00:00:00 2001
From: Tyler Veness <calcmogul@gmail.com>
Date: Thu, 10 Sep 2020 14:20:06 -0700
Subject: [PATCH] [wpimath] Use newer link to controls book in comments (NFC)
 (#2700)

---
 .../java/edu/wpi/first/wpilibj/estimator/KalmanFilter.java  | 3 ++-
 .../main/java/edu/wpi/first/wpilibj/geometry/Pose2d.java    | 6 +++---
 .../java/edu/wpi/first/wpilibj/system/LinearSystemLoop.java | 2 +-
 wpimath/src/main/native/include/frc/geometry/Pose2d.h       | 4 ++--
 wpimath/src/main/native/include/frc/system/LinearSystem.h   | 2 +-
 .../src/main/native/include/frc/system/LinearSystemLoop.h   | 2 +-
 6 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/wpimath/src/main/java/edu/wpi/first/wpilibj/estimator/KalmanFilter.java b/wpimath/src/main/java/edu/wpi/first/wpilibj/estimator/KalmanFilter.java
index 26af2e5873..99fa2b7fe8 100644
--- a/wpimath/src/main/java/edu/wpi/first/wpilibj/estimator/KalmanFilter.java
+++ b/wpimath/src/main/java/edu/wpi/first/wpilibj/estimator/KalmanFilter.java
@@ -29,7 +29,8 @@ import edu.wpi.first.wpiutil.math.numbers.N1;
  * the model.
  *
  * <p>For more on the underlying math, read
- * https://file.tavsys.net/control/controls-engineering-in-frc.pdf chapter 9.
+ * https://file.tavsys.net/control/controls-engineering-in-frc.pdf chapter 9 "Stochastic control
+ * theory".
  */
 @SuppressWarnings("ClassTypeParameterName")
 public class KalmanFilter<States extends Num, Inputs extends Num,
diff --git a/wpimath/src/main/java/edu/wpi/first/wpilibj/geometry/Pose2d.java b/wpimath/src/main/java/edu/wpi/first/wpilibj/geometry/Pose2d.java
index e75983f00a..a0e3b9ab6d 100644
--- a/wpimath/src/main/java/edu/wpi/first/wpilibj/geometry/Pose2d.java
+++ b/wpimath/src/main/java/edu/wpi/first/wpilibj/geometry/Pose2d.java
@@ -155,9 +155,9 @@ public class Pose2d {
   /**
    * Obtain a new Pose2d from a (constant curvature) velocity.
    *
-   * <p>See <a href="https://file.tavsys.net/control/state-space-guide.pdf">
-   * Controls Engineering in the FIRST Robotics Competition</a>
-   * section on nonlinear pose estimation for derivation.
+   * <p>See <a href="https://file.tavsys.net/control/controls-engineering-in-frc.pdf">
+   * Controls Engineering in the FIRST Robotics Competition</a> section 10.2 "Pose exponential" for
+   * a derivation.
    *
    * <p>The twist is a change in pose in the robot's coordinate frame since the
    * previous pose update. When the user runs exp() on the previous known
diff --git a/wpimath/src/main/java/edu/wpi/first/wpilibj/system/LinearSystemLoop.java b/wpimath/src/main/java/edu/wpi/first/wpilibj/system/LinearSystemLoop.java
index bc4f36d129..92357b39e0 100644
--- a/wpimath/src/main/java/edu/wpi/first/wpilibj/system/LinearSystemLoop.java
+++ b/wpimath/src/main/java/edu/wpi/first/wpilibj/system/LinearSystemLoop.java
@@ -32,7 +32,7 @@ import edu.wpi.first.wpiutil.math.numbers.N1;
  * input because that's what comes back from the sensors).
  *
  * <p>For more on the underlying math, read
- * https://file.tavsys.net/control/state-space-guide.pdf.
+ * https://file.tavsys.net/control/controls-engineering-in-frc.pdf.
  */
 @SuppressWarnings("ClassTypeParameterName")
 public class LinearSystemLoop<States extends Num, Inputs extends Num,
diff --git a/wpimath/src/main/native/include/frc/geometry/Pose2d.h b/wpimath/src/main/native/include/frc/geometry/Pose2d.h
index 76eeb90a8d..43f475699f 100644
--- a/wpimath/src/main/native/include/frc/geometry/Pose2d.h
+++ b/wpimath/src/main/native/include/frc/geometry/Pose2d.h
@@ -151,8 +151,8 @@ class Pose2d {
   /**
    * Obtain a new Pose2d from a (constant curvature) velocity.
    *
-   * See <https://file.tavsys.net/control/state-space-guide.pdf> section on
-   * nonlinear pose estimation for derivation.
+   * See https://file.tavsys.net/control/controls-engineering-in-frc.pdf section
+   * 10.2 "Pose exponential" for a derivation.
    *
    * The twist is a change in pose in the robot's coordinate frame since the
    * previous pose update. When the user runs exp() on the previous known
diff --git a/wpimath/src/main/native/include/frc/system/LinearSystem.h b/wpimath/src/main/native/include/frc/system/LinearSystem.h
index 7e4d8fec8b..975fa0ec70 100644
--- a/wpimath/src/main/native/include/frc/system/LinearSystem.h
+++ b/wpimath/src/main/native/include/frc/system/LinearSystem.h
@@ -23,7 +23,7 @@ namespace frc {
  * A plant is a mathematical model of a system's dynamics.
  *
  * For more on the underlying math, read
- * https://file.tavsys.net/control/state-space-guide.pdf.
+ * https://file.tavsys.net/control/controls-engineering-in-frc.pdf.
  */
 template <int States, int Inputs, int Outputs>
 class LinearSystem {
diff --git a/wpimath/src/main/native/include/frc/system/LinearSystemLoop.h b/wpimath/src/main/native/include/frc/system/LinearSystemLoop.h
index 229b24e25a..fc370c097a 100644
--- a/wpimath/src/main/native/include/frc/system/LinearSystemLoop.h
+++ b/wpimath/src/main/native/include/frc/system/LinearSystemLoop.h
@@ -29,7 +29,7 @@ namespace frc {
  * input because that's what comes back from the sensors).
  *
  * For more on the underlying math, read
- * https://file.tavsys.net/control/state-space-guide.pdf.
+ * https://file.tavsys.net/control/controls-engineering-in-frc.pdf.
  */
 template <int States, int Inputs, int Outputs>
 class LinearSystemLoop {