mc att: add unit tests for AttitudeControlMath helper

src/modules/mc_att_control/AttitudeControl/AttitudeControlMathTest.cpp

@@ -0,0 +1,92 @@
+/****************************************************************************
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+ ****************************************************************************/
+
+#include <gtest/gtest.h>
+
+#include "AttitudeControlMath.hpp"
+
+using namespace matrix;
+using namespace AttitudeControlMath;
+
+static const Vector3f z_unit(0.f, 0.f, 1.f);
+
+TEST(AttitudeControlMath, tiltCorrectionNoError)
+{
+	// GIVEN: some desired (non yaw-rotated) tilt setpoint
+	Quatf q_tilt_sp_ne(z_unit, Vector3f(-0.3, 0.1, 0.7));
+
+	// AND: a desired yaw setpoint
+	const Quatf q_sp_yaw = AxisAnglef(z_unit, -1.23f);
+
+	// WHEN: the current yaw error is zero (regardless of the tilt)
+	const Quatf q = q_sp_yaw * Quatf(z_unit, Vector3f(0.1f, -0.2f, 1.f));
+	const Quatf q_tilt_sp_ne_before = q_tilt_sp_ne;
+	correctTiltSetpointForYawError(q_tilt_sp_ne, q, q_sp_yaw);
+
+	// THEN: the tilt setpoint is unchanged
+	EXPECT_TRUE(isEqual(q_tilt_sp_ne_before, q_tilt_sp_ne));
+}
+
+TEST(AttitudeControlMath, tiltCorrectionYaw180)
+{
+	// GIVEN: some desired (non yaw-rotated) tilt setpoint and a desired yaw setpoint
+	Quatf q_tilt_sp_ne(z_unit, Vector3f(-0.3, 0.1, 0.7));
+	const Quatf q_sp_yaw = AxisAnglef(z_unit, -M_PI_F / 2.f);
+
+	// WHEN: there is a yaw error of 180 degrees
+	const Quatf q_yaw = Quatf(AxisAnglef(z_unit, M_PI_F / 2.f));
+	const Quatf q = q_yaw * Quatf(z_unit, Vector3f(0.1f, -0.2f, 1.f));
+	const Quatf q_tilt_sp_ne_before = q_tilt_sp_ne;
+	correctTiltSetpointForYawError(q_tilt_sp_ne, q, q_sp_yaw);
+
+	// THEN: the tilt is reversed (the corrected tilt angle is the same but the axis of rotation is opposite)
+	EXPECT_FLOAT_EQ(AxisAnglef(q_tilt_sp_ne_before).angle(), AxisAnglef(q_tilt_sp_ne).angle());
+	EXPECT_TRUE(isEqual(AxisAnglef(q_tilt_sp_ne_before).axis(), -AxisAnglef(q_tilt_sp_ne).axis()));
+}
+
+TEST(AttitudeControlMath, tiltCorrection)
+{
+	// GIVEN: some desired (non yaw-rotated) tilt setpoint and a desired yaw setpoint
+	Quatf q_tilt_sp_ne(z_unit, Vector3f(0.5, -0.1, 0.7));
+	const Quatf q_sp_yaw = AxisAnglef(z_unit, -1.23f);
+
+	// WHEN: there is a some yaw error
+	const Quatf q_yaw = Quatf(AxisAnglef(z_unit, 3.1f));
+	const Quatf q = q_yaw * Quatf(z_unit, Vector3f(0.1f, -0.2f, 1.f));
+	const Quatf q_tilt_sp_ne_before = q_tilt_sp_ne;
+	correctTiltSetpointForYawError(q_tilt_sp_ne, q, q_sp_yaw);
+
+	// THEN: the tilt vector obtained by rotating the corrected tilt by the yaw setpoint is the same as
+	// the one obtained by rotating the initial tilt by the current yaw of the vehicle
+	EXPECT_TRUE(isEqual((q_sp_yaw * q_tilt_sp_ne).dcm_z(), (q_yaw * q_tilt_sp_ne_before).dcm_z()));
+}

src/modules/mc_att_control/AttitudeControl/CMakeLists.txt

@@ -40,3 +40,4 @@ target_compile_options(AttitudeControl PRIVATE ${MAX_CUSTOM_OPT_LEVEL})
 target_include_directories(AttitudeControl PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
 
 px4_add_unit_gtest(SRC AttitudeControlTest.cpp LINKLIBS AttitudeControl)
+px4_add_unit_gtest(SRC AttitudeControlMathTest.cpp LINKLIBS AttitudeControl)