package org.opentrafficsim.road.gtu.lane.control;
   
   import org.djunits.value.vdouble.scalar.Acceleration;
   import org.opentrafficsim.base.parameters.ParameterException;
   import org.opentrafficsim.base.parameters.ParameterTypeDouble;
   import org.opentrafficsim.base.parameters.Parameters;
   import org.opentrafficsim.road.gtu.lane.LaneBasedGTU;
   import org.opentrafficsim.road.gtu.lane.perception.PerceptionCollectable;
   import org.opentrafficsim.road.gtu.lane.perception.headway.HeadwayGTU;
  
  /**
   * Linear CACC implementation based on derivatives by Jeroen Ploeg.
   * <p>
   * Copyright (c) 2013-2020 Delft University of Technology, PO Box 5, 2600 AA, Delft, the Netherlands. All rights reserved. <br>
   * BSD-style license. See <a href="http://opentrafficsim.org/node/13">OpenTrafficSim License</a>.
   * <p>
   * @version $Revision$, $LastChangedDate$, by $Author$, initial version Mar 13, 2019 <br>
   * @author <a href="http://www.tbm.tudelft.nl/averbraeck">Alexander Verbraeck</a>
   * @author <a href="http://www.tudelft.nl/pknoppers">Peter Knoppers</a>
   * @author <a href="http://www.transport.citg.tudelft.nl">Wouter Schakel</a>
   */
  public class PloegCACC extends PloegACC
  {
  
      /** Acceleration error gain parameter. */
      public static final ParameterTypeDouble KA = LinearCACC.KA;
  
      /**
       * Constructor using default sensors with no delay.
       * @param delayedActuation DelayedActuation; delayed actuation
       */
      public PloegCACC(final DelayedActuation delayedActuation)
      {
          super(delayedActuation);
      }
  
      /** {@inheritDoc} */
      @Override
      public Acceleration getFollowingAcceleration(final LaneBasedGTU gtu,
              final PerceptionCollectable<HeadwayGTU, LaneBasedGTU> leaders, final Parameters settings) throws ParameterException
      {
          HeadwayGTU leader = leaders.first();
          if (leader.getAcceleration() == null)
          {
              return super.getFollowingAcceleration(gtu, leaders, settings);
          }
          double es =
                  leader.getDistance().si - gtu.getSpeed().si * settings.getParameter(TDCACC).si - settings.getParameter(X0).si;
          double esd = leader.getSpeed().si - gtu.getSpeed().si - gtu.getAcceleration().si * settings.getParameter(TDCACC).si;
          double kaui = settings.getParameter(KA) * leader.getAcceleration().si;
          return Acceleration.instantiateSI(settings.getParameter(KS) * es + settings.getParameter(KD) * esd + kaui);
      }
  
  }