Merge pull request RobotLocomotion#8411 from RussTedrake/care_doc

minor cleanup on CARE documentation.
notokay · Mar 21, 2018 · a692ae5 · a692ae5
2 parents 0f0aec1 + 89d9491
commit a692ae5
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diff --git a/math/continuous_algebraic_riccati_equation.h b/math/continuous_algebraic_riccati_equation.h
@@ -5,11 +5,11 @@
 namespace drake {
 namespace math {
 
-/// Computes the unique stabilizing solution X to the continuous-time algebraic
+/// Computes the unique stabilizing solution S to the continuous-time algebraic
 /// Riccati equation:
 ///
 /// @verbatim
-///  S'A + A'S - S B inv(R) B' S + Q = 0
+///  S A + A' S - S B inv(R) B' S + Q = 0
 /// @endverbatim
 ///
 /// @throws std::runtime_error if R is not positive definite.

diff --git a/math/test/continuous_algebraic_riccati_equation_test.cc b/math/test/continuous_algebraic_riccati_equation_test.cc
@@ -50,6 +50,16 @@ GTEST_TEST(CARE, TestCare) {
   SolveCAREandVerify(A1, B1, Q, R1);
 }
 
+// Test the stabilization of the linearized pendulum (at the top).
+GTEST_TEST(CARE, TestCare2) {
+  MatrixXd A1(2, 2), B1(2, 1), Q(2, 2), R1(1, 1);
+  A1 << 0, 1, 10, 0;
+  B1 << 0, 1;
+  Q << 1, 0, 0, 1;
+  R1 << 1;
+  SolveCAREandVerify(A1, B1, Q, R1);
+}
+
 }  // namespace
 }  // namespace math
 }  // namespace drake