improve examples, add setTargetTimedMovePreferred

Author: joshua-8

examples/SmoothServoTimeBased/SmoothServoTimeBased.ino

@@ -24,14 +24,14 @@ void loop()
         if (state == true)
             limiter.setTargetAndVelLimitForTimedMove(0, 10);
         state = false;
-        myServo.write(limiter.calc());
         limiter.calc();
+        myServo.write(limiter.getPosition());
     } else {
         if (state == false)
             limiter.setTargetAndVelLimitForTimedMove(180, 10);
         state = true;
-        myServo.write(limiter.calc());
         limiter.calc();
+        myServo.write(limiter.getPosition());
     }
     Serial.print(limiter.getPosition());
     Serial.print(",");

examples/TimeBased/TimeBased.ino

@@ -0,0 +1,37 @@
+/**
+ * TimeBased, an example for the Derivs_Limiter library
+ * https://github.com/joshua-8/Derivs_Limiter
+ * 
+ * Open the serial plotter to see the smoothed position values.
+ * Every 15 seconds the values should move for 10 seconds.
+ */
+#include <Arduino.h>
+#include <Derivs_Limiter.h>
+
+Derivs_Limiter limiter = Derivs_Limiter(14, 20); // velocityLimit, accelerationLimit
+
+boolean state = true;
+void setup()
+{
+    Serial.begin(9600);
+}
+void loop()
+{
+    if (millis() % 30000 < 15000) { //toggles every 15 seconds
+        if (state == true) //important to only start timed move once
+            limiter.setTargetAndVelLimitForTimedMove(0, 10);
+        state = false;
+        limiter.calc();
+    } else {
+        if (state == false) //important to only start timed move once
+            limiter.setTargetAndVelLimitForTimedMove(15, 10);
+        state = true;
+        limiter.calc();
+    }
+    Serial.print(limiter.getPosition(), 4);
+    Serial.print(",");
+    Serial.print(limiter.getVelocity());
+    Serial.print(",");
+    Serial.print(limiter.getAcceleration());
+    Serial.println();
+}

library.properties

@@ -1,5 +1,5 @@
 name=Derivs_Limiter
-version=2.6.0
+version=2.6.1
 author=Joshua Phelps <[email protected]>
 maintainer=Joshua Phelps <[email protected]>
 sentence=This library can be used to limit the first and second derivative of a variable as it approaches a target value.

src/Derivs_Limiter.h

@@ -517,7 +517,7 @@ class Derivs_Limiter {
     }
 
     /**
-     * @brief  This function changes velLimit so that a move to the specified target position takes the specified time (if possible given acceleration limit) use like setTarget()
+     * @brief  This function changes velLimit so that a move to the specified target position takes the specified time (if possible given acceleration limit)
      * @note   using this function changes the value of velLimit from whatever you set it to when you created the Derivs_Limiter object
      * @param  _target: (float) position you'd like to move to
      * @param  _time: (float) how long you would like the movement to take
@@ -532,6 +532,29 @@ class Derivs_Limiter {
         return ret;
     }
 
+    /**
+     * @brief  This function changes velLimit so that a move to the specified target position takes the specified time if possible given acceleration limit, and if not possible resets the velocity limit to the original value (or _maxVel if not NAN) and goes to the target at that speed instead
+     * @note   using this function changes the value of velLimit from whatever you set it to when you created the Derivs_Limiter object
+     * @param  _target: (float) position you'd like to move to
+     * @param  _time: (float) how long you would like the movement to take
+     * @param  _maxVel: (float, optional, default=NAN) maximum allowable velocity, if the required velocity exceeds this the function returns false, if NAN the velocity limit set in the constructor or setVelLimit() is used
+     * @retval (bool) true if move possible within time given acceleration limit, false if not possible (and move happens with maxVel instead but will not complete in time)
+     */
+    boolean setTargetTimedMovePreferred(float _target, float _time, float _maxVel = NAN)
+    {
+        boolean ret = setVelLimitForTimedMove(_target - position, _time, _maxVel);
+        if (ret)
+            target = _target;
+        else { //not possible in time given acceleration
+            if (isnan(_maxVel))
+                resetVelLimitToOriginal();
+            else
+                velLimit = _maxVel;
+            target = _target;
+        }
+        return ret;
+    }
+
 protected:
     /**
      * @brief  this is where the actual code is