FlightTaskManualAltitude: replace 0 check with FLT_EPSILON

src/lib/FlightTasks/tasks/Manual/FlightTaskManual.cpp

@@ -74,17 +74,17 @@ bool FlightTaskManual::_evaluateSticks()
 	/* Sticks are rescaled linearly and exponentially to [-1,1] */
 	if ((_time_stamp_current - _sub_manual_control_setpoint->get().timestamp) < rc_timeout) {
 
-		/* Linear scale  */
+		// Linear scale
 		_sticks(0) = _sub_manual_control_setpoint->get().x; /* NED x, "pitch" [-1,1] */
 		_sticks(1) = _sub_manual_control_setpoint->get().y; /* NED y, "roll" [-1,1] */
 		_sticks(2) = -(_sub_manual_control_setpoint->get().z - 0.5f) * 2.f; /* NED z, "thrust" resacaled from [0,1] to [-1,1] */
 		_sticks(3) = _sub_manual_control_setpoint->get().r; /* "yaw" [-1,1] */
 
-		/* Exponential scale */
-		_sticks_expo(0) = math::expo_deadzone(_sticks(0), _xy_vel_man_expo.get(), _stick_dz.get());
-		_sticks_expo(1) = math::expo_deadzone(_sticks(1), _xy_vel_man_expo.get(), _stick_dz.get());
-		_sticks_expo(2) = math::expo_deadzone(_sticks(2), _z_vel_man_expo.get(), _stick_dz.get());
-		_sticks_expo(3) = math::expo_deadzone(_sticks(3), _yaw_expo.get(), _stick_dz.get());
+		// Exponential scale
+		_sticks_expo(0) = math::expo_deadzone(_sticks(0), _xy_vel_man_expo.get(), MPC_HOLD_DZ.get());
+		_sticks_expo(1) = math::expo_deadzone(_sticks(1), _xy_vel_man_expo.get(), MPC_HOLD_DZ.get());
+		_sticks_expo(2) = math::expo_deadzone(_sticks(2), _z_vel_man_expo.get(), MPC_HOLD_DZ.get());
+		_sticks_expo(3) = math::expo_deadzone(_sticks(3), _yaw_expo.get(), MPC_HOLD_DZ.get());
 
 		// Only switch the landing gear up if the user switched from gear down to gear up.
 		// If the user had the switch in the gear up position and took off ignore it

src/lib/FlightTasks/tasks/Manual/FlightTaskManual.hpp

@@ -60,7 +60,7 @@ class FlightTaskManual : public FlightTask
 	matrix::Vector<float, 4> _sticks; /**< unmodified manual stick inputs */
 	matrix::Vector<float, 4> _sticks_expo; /**< modified manual sticks using expo function*/
 
-	float stickDeadzone() const { return _stick_dz.get(); }
+	float stickDeadzone() const { return MPC_HOLD_DZ.get(); }
 
 private:
 
@@ -70,7 +70,7 @@ class FlightTaskManual : public FlightTask
 	uORB::Subscription<manual_control_setpoint_s> *_sub_manual_control_setpoint{nullptr};
 
 	DEFINE_PARAMETERS_CUSTOM_PARENT(FlightTask,
-					(ParamFloat<px4::params::MPC_HOLD_DZ>) _stick_dz, /**< 0-deadzone around the center for the sticks */
+					(ParamFloat<px4::params::MPC_HOLD_DZ>) MPC_HOLD_DZ, /**< 0-deadzone around the center for the sticks */
 					(ParamFloat<px4::params::MPC_XY_MAN_EXPO>)
 					_xy_vel_man_expo, /**< ratio of exponential curve for stick input in xy direction */
 					(ParamFloat<px4::params::MPC_Z_MAN_EXPO>)

src/lib/FlightTasks/tasks/ManualAltitude/FlightTaskManualAltitude.cpp

@@ -94,12 +94,12 @@ void FlightTaskManualAltitude::_scaleSticks()
 	FlightTaskManualStabilized::_scaleSticks();
 
 	// scale horizontal velocity with expo curve stick input
-	const float vel_max_z = (_sticks(2) > 0.0f) ? _constraints.speed_down : _constraints.speed_up;
+	float vel_max_z = (_sticks_expo(2) > FLT_EPSILON) ? _constraints.speed_down : _constraints.speed_up;
 	_velocity_setpoint(2) = vel_max_z * _sticks_expo(2);
 
 	// if there is a valid distance to bottom or distance to home, then
 	// adjust speed downwards gradually within the limits MPC_LAND_ALT1 and MPC_LAND_ALT2.
-	if (_sticks(2) > 0.0f) { //user demands speed downwards
+	if (_sticks_expo(2) > FLT_EPSILON) { //user demands speed downwards
 
 		float dist_to_ground = NAN;
 

src/lib/FlightTasks/tasks/ManualAltitude/FlightTaskManualAltitude.hpp

@@ -66,7 +66,7 @@ class FlightTaskManualAltitude : public FlightTaskManualStabilized
 					(ParamFloat<px4::params::MPC_HOLD_MAX_Z>) MPC_HOLD_MAX_Z,
 					(ParamInt<px4::params::MPC_ALT_MODE>) MPC_ALT_MODE,
 					(ParamFloat<px4::params::MPC_HOLD_MAX_XY>) MPC_HOLD_MAX_XY,
-					(ParamFloat<px4::params::MPC_Z_P>) MPC_Z_P
+					(ParamFloat<px4::params::MPC_Z_P>) MPC_Z_P,
 					(ParamFloat<px4::params::MPC_LAND_ALT1>) MPC_LAND_ALT1, // altitude at which speed limit downwards reaches maximum speed
 					(ParamFloat<px4::params::MPC_LAND_ALT2>) MPC_LAND_ALT2, // altitude at which speed limit downwards reached minimum speed
 					(ParamFloat<px4::params::MPC_LAND_SPEED>) MPC_LAND_SPEED