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--- marvin:lab8 [2008/11/09 10:21] – deva
+++ marvin:lab8 [2008/11/09 10:29] – deva
@@ Line 55: / Line 55: @@
 this array is copied and stored in the constructor of each Behavior, and can then be iterated whenever suppression of the lower levels are needed.
 <code java>
-private ArrayList behaviors;;
+private ArrayList behaviors;
 public Behavior(String name, ArrayList behaviors)
@@ Line 82: / Line 82: @@
 ====Java Thread====
 The ''Behavior'' class extends ''Thread'' which makes it run as a thread in the JVM. The thread is configured to run as //daemon// which makes it automatically terminate together with the main thread(([[http://java.sun.com/j2se/1.4.2/docs/api/java/lang/Thread.html#setDaemon(boolean)]])).
 ====Threaded implementation of "Driving Towards Light"====
-Bent writes this part
+The ''DriveTowardsLight'' class was implemented based on the code from [[marvin:lab7]].\\
+The wanted behavior is the following:
+  * suppress lower behaviors
+  * read light values
+  * assign modified light values as motor power (l1 -> m2, l2 -> m1).
+  * unsuppress lower behaviors
+Here is the most important code from the class:
+<code java>
+private LightSensor l1;
+private LightSensor l2;
+private int offset = 60;
+public DriveTowardsLight(String name, ArrayList behaviors)
+{
+  ...
+  l1 = new LightSensor(SensorPort.S2);
+  l2 = new LightSensor(SensorPort.S3);
+  l1.setFloodlight(false);
+  l2.setFloodlight(false);
+}
+public void run()
+{
+  while (true)
+  {
+    // Read value from light sensors
+    int val1 = l1.readValue() + offset;
+    int val2 = l2.readValue() + offset;
+    suppressLower();
+    forward(val2, val1);
+    delay(500);
+    unsuppressLower();
+}
+</code>
+This code however would take over entirely the control of the car since it is active all the time.\\
+We therefore introduced a light threshold to make the car search for light, only when there is some light to search for.\\
+the code for that is shown below:
+<code java>
+private int threshold = 80;
+public void run()
+{
+  .
+  .
+  .
+  if(val1 > threshold || val2 > threshold) {
+    suppressLower();
+    forward(val2, val1);
+    delay(500);
+    unsuppressLower();
+  }
+}
+</code>
 **Video for "Drive towards light test"**\\