Added smithPredictor to ltisys. bump to 1.3.7

Author: camilo

library.json

@@ -16,7 +16,7 @@
       "maintainer": true
     }
   ],
-  "version": "1.3.6",
+  "version": "1.3.7",
   "license": "MIT",
   "frameworks": "arduino",
   "platforms": "*"

library.properties

@@ -1,5 +1,5 @@
 name=qlibs
-version=1.3.6
+version=1.3.7
 license=MIT
 author=J. Camilo Gomez C. <[email protected]>
 maintainer=J. Camilo Gomez C. <[email protected]>

src/CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required( VERSION 3.2 )
 project( qlibs-cpp
-         VERSION 1.3.6
+         VERSION 1.3.7
          DESCRIPTION "A collection of useful C++ libraries for embedded systems"
          LANGUAGES CXX )
 

src/include/ltisys.hpp

@@ -137,6 +137,16 @@ namespace qlibs {
         return static_cast<size_t>( ( Time.value/dt ) + 0.5_re );
     }
 
+    /** @cond **/
+    class ITransportDelay {
+    public:
+        virtual ~ITransportDelay() = default;
+        virtual real_t delay(const real_t xInput) noexcept = 0;
+        virtual real_t operator()(const real_t xInput) noexcept = 0;
+        virtual size_t getNumberOfDelays() const noexcept = 0;
+    };
+    /** @cond **/
+
     /**
     * @brief Delays the input by a specified amount of time. You can use this
     * class to simulate a time delay.
@@ -150,11 +160,12 @@ namespace qlibs {
     * @endcode
     */
     template<size_t numberOfDelays>
-    class transportDelay {
+    class transportDelay : public ITransportDelay {
         private:
             real_t buf[ numberOfDelays + 1 ];
-            tdl delay;
+            tdl dl;
         public:
+            virtual ~transportDelay() {}
             /**
             * @brief Constructor for the transportDelay class
             * @param[in] initValue The output generated by the block between the
@@ -163,17 +174,28 @@ namespace qlibs {
             transportDelay( const real_t initValue = 0.0_re )
             {
                 static_assert( numberOfDelays >= 1 , "Delay taps should be greater than 0" );
-                delay.setup( buf, initValue);
+                dl.setup( buf, initValue);
+            }
+
+            /**
+            * @brief Delays the input by a specified amount of time.
+            * @param[in] xInput The signal to be delayed.
+            * @return The delayed input signal
+            */
+            real_t delay( const real_t xInput ) noexcept override
+            {
+                dl.insertSample( xInput );
+                return dl.getOldest();
             }
+
             /**
             * @brief Delays the input by a specified amount of time.
             * @param[in] xInput The signal to be delayed.
             * @return The delayed input signal
             */
-            real_t operator()( const real_t xInput ) noexcept
+            real_t operator()( const real_t xInput ) noexcept override
             {
-                delay.insertSample( xInput );
-                return delay.getOldest();
+                return delay( xInput );
             }
 
             constexpr size_t getNumberOfDelays() const noexcept {
@@ -276,7 +298,7 @@ namespace qlibs {
             * @param[in] u A new input sample that excites (drives) the system.
             * @return The system's output (response) at the current time step.
             */
-            real_t excite( real_t u );
+            real_t excite( real_t u ) noexcept;
 
             /// @copydoc excite(real_t)
             real_t operator()( const real_t u ) {
@@ -721,6 +743,104 @@ namespace qlibs {
             bool setIntegrationMethod( integrationMethod m );
     };
 
+    /**
+     * @brief A Smith Predictor implementation for compensating time delays in
+     * control systems.
+     * @details The Smith Predictor is a model-based feedforward control strategy
+     * designed to improve performance in systems with significant dead time.
+     * It estimates the delay-free output using an internal model of the process,
+     * a delay block, and optionally an output filter model.
+     */
+    class smithPredictor {
+    private:
+        ltisys *model;
+        ITransportDelay *modelDelay;
+        ltisys *filter{ nullptr };
+        real_t yp_hat;
+    public:
+        virtual ~smithPredictor() {}
+        /**
+         * @brief Constructs a Smith Predictor with a plant model, delay model,
+         * and optional initial output estimate.
+         * @param[in] modelTf Reference to the LTI system model representing the
+         * delay-free plant.
+         * @param[in] mDelay Reference to the transport delay block modeling the
+         * plant’s dead time.
+         * @param[in] initialCondition Initial value for the internal output
+         * prediction (@c yp_hat). Default is 0.0.
+         *
+         * @note Both the model and delay block are passed by reference and stored internally as pointers.
+         */
+        smithPredictor( ltisys& modelTf,
+                        ITransportDelay& mDelay,
+                        const real_t initialCondition = 0.0_re )
+                        : model(&modelTf), modelDelay(&mDelay), yp_hat(initialCondition) {}
+
+        /**
+         * @brief Constructs a Smith Predictor with a plant model, delay model,
+         * and optional initial output estimate.
+         * @param[in] modelTf Reference to the LTI system model representing the
+         * delay-free plant.
+         * @param[in] mDelay Reference to the transport delay block modeling the
+         * plant’s dead time.
+         * @param[in] filterTf Reference to the LTI system used as the robustness
+         * filter.
+         * @param[in] initialCondition Initial value for the internal output
+         * prediction (@c yp_hat). Default is 0.0.
+         *
+         * @note Both the model and delay block are passed by reference and stored internally as pointers.
+         */
+        smithPredictor( ltisys& modelTf,
+                        ITransportDelay& mDelay,
+                        ltisys& filterTf,
+                        const real_t initialCondition = 0.0_re )
+                        : model(&modelTf), modelDelay(&mDelay), filter(&filterTf), yp_hat(initialCondition) {}
+
+        /**
+         * @brief Updates the internal prediction based on control input and
+         * measured plant output.
+         * @details This method should be called at each control step. It updates
+         * the internal predicted output by propagating the input through the
+         * internal delay-free model and adjusting the prediction using the
+         * actual plant output.
+         *
+         * @param[in] ut The control input applied to the real plant.
+         * @param[in] yt The actual measured output from the delayed plant.
+         * @return @c true if the prediction was successfully updated, @c false otherwise.
+         *
+         * @note The time-step used to call this function must match the time
+         * base used by both the plant model and the delay block.
+         */
+        bool updatePrediction( const real_t ut,
+                               const real_t yt ) noexcept;
+
+        /**
+         * @brief Retrieves the current delay-free predicted output of the system.
+         * @return The internally computed predicted output.
+         */
+        real_t getPrediction() const noexcept {
+            return yp_hat;
+        }
+
+        /**
+         * @brief Sets an optional filter for the internal Smith Predictor model.
+         * @details The filter is used to improve the system's robustness, attenuate
+         * measurement noise, and ensure internal stability, particularly in the case
+         * of unstable plant dynamics.
+         *
+         * @param[in] filterTf Reference to the LTI system used as the robustness
+         * filter.
+         * @return @c true if the filter was set successfully.
+         *
+         * @note The filter is applied internally to the model-based prediction
+         * and does not affect the plant or delay block directly.
+         */
+        bool setFilter( ltisys& filterTf ) noexcept {
+            filter = &filterTf;
+            return true;
+        }
+    };
+
     /** @}*/
 }
 

src/ltisys.cpp

@@ -62,7 +62,7 @@ bool ltisys::setSaturation( const real_t minV,
     return retValue;
 }
 /*============================================================================*/
-real_t ltisys::excite( real_t u )
+real_t ltisys::excite( real_t u ) noexcept
 {
     real_t y = 0.0_re;
 
@@ -283,4 +283,15 @@ bool continuousSystem::setIntegrationMethod( integrationMethod m )
 
     return retValue;
 }
+/*============================================================================*/
+bool smithPredictor::updatePrediction( const real_t ut,
+                                       const real_t yt ) noexcept
+{
+    const real_t yt_hat_d = model->excite( ut );
+    const real_t yt_hat = modelDelay->delay( yt_hat_d );
+    const real_t ep_hat = yt - yt_hat;
+
+    yp_hat = yt_hat_d + ( filter ? filter->excite( ep_hat ) : ep_hat );
+    return true;
+}
 /*============================================================================*/

src/qlibs.h

@@ -1,7 +1,7 @@
 /*!
  * @file qlibs.h
  * @author J. Camilo Gomez C.
- * @version 1.3.6
+ * @version 1.3.7
  * @note This file is part of the qlibs++ distribution.
  * @brief Global inclusion header
  **/
@@ -41,8 +41,8 @@ This file is part of the QuarkTS++ OS distribution.
 #ifndef QLIBS_CPP_H
 #define QLIBS_CPP_H
 
-    #define QLIBS_CPP_VERSION         "1.3.6"
-    #define QLIBS_CPP_VERNUM          ( 136 )
+    #define QLIBS_CPP_VERSION         "1.3.7"
+    #define QLIBS_CPP_VERNUM          ( 137 )
     #define QLIBS_CPP_CAPTION         "qLibs++ " QLIBS_CPP_VERSION
 
     #include <include/qlibs_types.hpp>
@@ -62,7 +62,7 @@ This file is part of the QuarkTS++ OS distribution.
 
     namespace qlibs {
         namespace build {
-            constexpr const uint32_t number = 2388;
+            constexpr const uint32_t number = 2397;
             constexpr const char* date = __DATE__;
             constexpr const char* time = __TIME__;
             constexpr const char* std = "c++11";
@@ -72,7 +72,7 @@ This file is part of the QuarkTS++ OS distribution.
             constexpr const uint8_t number = QLIBS_CPP_VERNUM;
             constexpr const uint8_t mayor = 1U;
             constexpr const uint8_t minor = 3U;
-            constexpr const uint8_t rev = 6U;
+            constexpr const uint8_t rev = 7U;
         }
         namespace product {
             constexpr const char* author = "J. Camilo Gomez C.";