diff options
Diffstat (limited to 'src/modules/controllib/blocks.hpp')
| -rw-r--r-- | src/modules/controllib/blocks.hpp | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/src/modules/controllib/blocks.hpp b/src/modules/controllib/blocks.hpp index 66e929038..bffc355a8 100644 --- a/src/modules/controllib/blocks.hpp +++ b/src/modules/controllib/blocks.hpp @@ -114,7 +114,7 @@ public: // methods BlockLowPass(SuperBlock *parent, const char *name) : Block(parent, name), - _state(0), + _state(0.0f/0.0f /* initialize to invalid val, force into is_finite() check on first call */), _fCut(this, "") // only one parameter, no need to name {}; virtual ~BlockLowPass() {}; @@ -238,9 +238,25 @@ public: BlockDerivative(SuperBlock *parent, const char *name) : SuperBlock(parent, name), _u(0), + _initialized(false), _lowPass(this, "LP") {}; virtual ~BlockDerivative() {}; + + /** + * Update the state and get current derivative + * + * This call updates the state and gets the current + * derivative. As the derivative is only valid + * on the second call to update, it will return + * no change (0) on the first. To get a closer + * estimate of the derivative on the first call, + * call setU() one time step before using the + * return value of update(). + * + * @param input the variable to calculate the derivative of + * @return the current derivative + */ float update(float input); // accessors void setU(float u) {_u = u;} @@ -249,6 +265,7 @@ public: protected: // attributes float _u; /**< previous input */ + bool _initialized; BlockLowPass _lowPass; /**< low pass filter */ }; |