diff --git a/app/src/main/java/com/google/ar/core/examples/java/helloar/HelloArActivity.java b/app/src/main/java/com/google/ar/core/examples/java/helloar/HelloArActivity.java
index 80e10bd..f55bac4 100644
--- a/app/src/main/java/com/google/ar/core/examples/java/helloar/HelloArActivity.java
+++ b/app/src/main/java/com/google/ar/core/examples/java/helloar/HelloArActivity.java
@@ -32,6 +32,7 @@
 import com.google.ar.core.Point;
 import com.google.ar.core.Point.OrientationMode;
 import com.google.ar.core.PointCloud;
+import com.google.ar.core.Pose;
 import com.google.ar.core.Session;
 import com.google.ar.core.Trackable;
 import com.google.ar.core.TrackingState;
@@ -40,7 +41,13 @@
 import com.google.ar.core.examples.java.common.framework.model3D.ModelFileFormatException;
 import com.google.ar.core.examples.java.common.framework.model3D.Object3D;
 import com.google.ar.core.examples.java.common.framework.model3D.Position3D;
+import com.google.ar.core.examples.java.common.framework.model3D.Quaternion3D;
 import com.google.ar.core.examples.java.common.framework.model3D.Universe;
+import com.google.ar.core.examples.java.common.framework.physics.AngularVelocity3D;
+import com.google.ar.core.examples.java.common.framework.physics.Force3D;
+import com.google.ar.core.examples.java.common.framework.physics.Ground;
+import com.google.ar.core.examples.java.common.framework.physics.PhysicalSystem;
+import com.google.ar.core.examples.java.common.framework.physics.Solid3D;
 import com.google.ar.core.examples.java.common.helpers.CameraPermissionHelper;
 import com.google.ar.core.examples.java.common.helpers.DisplayRotationHelper;
 import com.google.ar.core.examples.java.common.helpers.FullScreenHelper;
@@ -48,6 +55,7 @@
 import com.google.ar.core.examples.java.common.helpers.TapHelper;
 import com.google.ar.core.examples.java.common.helpers.TrackingStateHelper;
 import com.google.ar.core.examples.java.common.java3d.Appearance;
+import com.google.ar.core.examples.java.common.java3d.Box;
 import com.google.ar.core.examples.java.common.java3d.Material;
 import com.google.ar.core.examples.java.common.rendering.BackgroundRenderer;
 import com.google.ar.core.examples.java.common.rendering.ObjectRenderer;
@@ -62,6 +70,8 @@
 import com.google.ar.core.exceptions.UnavailableUserDeclinedInstallationException;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Collection;
+
 import javax.microedition.khronos.egl.EGLConfig;
 import javax.microedition.khronos.opengles.GL10;
 
@@ -77,6 +87,8 @@
   private GLSurfaceView surfaceView;
   private RWTRenderer renderer;
   private Universe universe;
+  private PhysicalSystem physicalSystem;
+  private Ground ground = null;
 
   private boolean installRequested;
 
@@ -111,6 +123,8 @@
 
   private final ArrayList<ColoredAnchor> anchors = new ArrayList<>();
 
+  private Collection<Plane> placedPlanes = new ArrayList<>();
+
   private float ambient = 0.3f;
   private float diffuse = 1.0f;
   private float specular = 1.0f;
@@ -140,15 +154,18 @@
     surfaceView.setWillNotDraw(false);
 
     installRequested = false;
-    try {
-      Object3D andy = ModelFactory.loadModel(getResources(), "models/andy.obj", null).createObject();
-      andy.setPosition(new Position3D(0.0, 0.0, -1.0));
-      universe.place(andy);
-    } catch (IOException e) {
-      e.printStackTrace();
-    } catch (ModelFileFormatException e) {
-      e.printStackTrace();
-    }
+
+    // For Radish
+    physicalSystem = new PhysicalSystem();
+//    try {
+//      Object3D andy = ModelFactory.loadModel(getResources(), "models/andy.obj", null).createObject();
+//      andy.setPosition(new Position3D(0.0, 0.0, -1.0));
+//      universe.place(andy);
+//    } catch (IOException e) {
+//      e.printStackTrace();
+//    } catch (ModelFileFormatException e) {
+//      e.printStackTrace();
+//    }
   }
 
   @Override
@@ -299,6 +316,11 @@
       // Handle one tap per frame.
       handleTap(frame, camera);
 
+      // Physics
+      if (physicalSystem.objects.size() > 0) {
+        physicalSystem.motion(0, 1, Force3D.ZERO, physicalSystem.objects.get(0).getGravityCenter(), ground);
+      }
+
       // If frame is ready, render camera preview image to the GL surface.
 //      backgroundRenderer.draw(frame);
 
@@ -340,7 +362,23 @@
         messageSnackbarHelper.showMessage(this, SEARCHING_PLANE_MESSAGE);
       }
 
-//      // Visualize planes.
+      // Visualize planes.
+      Collection<Plane> currentPlanes = session.getAllTrackables(Plane.class);
+      for (Plane plane : currentPlanes) {
+        if (!placedPlanes.contains(plane)) {
+          placedPlanes.add(plane);
+          Box rect = new Box(plane.getExtentX() / 2, 0.1f, plane.getExtentZ() / 2, null);
+          Object3D rectObj = new Object3D("plane", rect);
+          Pose p = plane.getCenterPose();
+          rectObj.apply(new Position3D(p.tx(), p.ty(), p.tz()), false);
+          rectObj.apply(new Quaternion3D((double)p.qx(), (double)p.qy(), (double)p.qz(), (double)p.qw()), false);
+          if (ground == null) {
+            ground = new Ground(rectObj);
+            universe.place(ground);
+          }
+        }
+      }
+
 //      planeRenderer.drawPlanes(
 //          session.getAllTrackables(Plane.class), camera.getDisplayOrientedPose(), projmtx);
 //
@@ -414,8 +452,10 @@
 
           try {
             Object3D andy = ModelFactory.loadModel(getResources(), "models/andy.obj", null).createObject();
-            andy.setPosition(new Position3D(px, py, pz));
-            universe.place(andy);
+            andy.setPosition(new Position3D(px, py + 0.2, pz));
+            Solid3D andyObj = new Solid3D(andy);
+            universe.place(andyObj);
+            physicalSystem.add(andyObj);
           } catch (IOException e) {
             e.printStackTrace();
           } catch (ModelFileFormatException e) {