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 f55bac4..ad4b63b 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
@@ -37,6 +37,9 @@
 import com.google.ar.core.Trackable;
 import com.google.ar.core.TrackingState;
 import com.google.ar.core.examples.java.common.framework.RWT.RWTRenderer;
+import com.google.ar.core.examples.java.common.framework.gameMain.OvergroundActor;
+import com.google.ar.core.examples.java.common.framework.model3D.BaseObject3D;
+import com.google.ar.core.examples.java.common.framework.model3D.CollisionResult;
 import com.google.ar.core.examples.java.common.framework.model3D.ModelFactory;
 import com.google.ar.core.examples.java.common.framework.model3D.ModelFileFormatException;
 import com.google.ar.core.examples.java.common.framework.model3D.Object3D;
@@ -48,6 +51,7 @@
 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.framework.physics.Velocity3D;
 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;
@@ -57,6 +61,9 @@
 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.java3d.Transform3D;
+import com.google.ar.core.examples.java.common.java3d.TransparencyAttributes;
+import com.google.ar.core.examples.java.common.java3d.Vector3d;
 import com.google.ar.core.examples.java.common.rendering.BackgroundRenderer;
 import com.google.ar.core.examples.java.common.rendering.ObjectRenderer;
 import com.google.ar.core.examples.java.common.rendering.ObjectRenderer.BlendMode;
@@ -71,6 +78,9 @@
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
 
 import javax.microedition.khronos.egl.EGLConfig;
 import javax.microedition.khronos.opengles.GL10;
@@ -121,9 +131,20 @@
     }
   }
 
+  static class SortablePlane {
+    final float distance;
+    final Plane plane;
+
+    SortablePlane(float distance, Plane plane) {
+      this.distance = distance;
+      this.plane = plane;
+    }
+  }
+
   private final ArrayList<ColoredAnchor> anchors = new ArrayList<>();
 
   private Collection<Plane> placedPlanes = new ArrayList<>();
+  private Plane placedPlane = null;
 
   private float ambient = 0.3f;
   private float diffuse = 1.0f;
@@ -156,7 +177,7 @@
     installRequested = false;
 
     // For Radish
-    physicalSystem = new PhysicalSystem();
+//    physicalSystem = new PhysicalSystem();
 //    try {
 //      Object3D andy = ModelFactory.loadModel(getResources(), "models/andy.obj", null).createObject();
 //      andy.setPosition(new Position3D(0.0, 0.0, -1.0));
@@ -317,9 +338,10 @@
       handleTap(frame, camera);
 
       // Physics
-      if (physicalSystem.objects.size() > 0) {
-        physicalSystem.motion(0, 1, Force3D.ZERO, physicalSystem.objects.get(0).getGravityCenter(), ground);
-      }
+      universe.update(10);
+//      if (physicalSystem.objects.size() > 0) {
+//        physicalSystem.motion(0, 10, Force3D.ZERO, physicalSystem.objects.get(0).getGravityCenter(), ground);
+//      }
 
       // If frame is ready, render camera preview image to the GL surface.
 //      backgroundRenderer.draw(frame);
@@ -363,19 +385,32 @@
       }
 
       // 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);
+      Collection<Plane> allPlanes = session.getAllTrackables(Plane.class);
+      for (Plane plane : allPlanes) {
+        if (placedPlane == null) {
+          placedPlane = plane;
+          Appearance ap = new Appearance();
+          ap.setTransparencyAttributes(new TransparencyAttributes(TransparencyAttributes.BLENDED, 0.5f));
+          Box rect = new Box(plane.getExtentX() / 2, 0.005f, plane.getExtentZ() / 2, ap);
           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);
-          }
+          rectObj.apply(new Quaternion3D((double) p.qx(), (double) p.qy(), (double) p.qz(), (double) p.qw()), false);
+          ground = new Ground(rectObj);
+          universe.place(ground);
+        }
+      }
+      Collection<Plane> updatedPlanes = frame.getUpdatedTrackables(Plane.class);
+      for(Plane plane : updatedPlanes) {
+      if (plane == placedPlane) {
+          Appearance ap = new Appearance();
+          ap.setTransparencyAttributes(new TransparencyAttributes(TransparencyAttributes.BLENDED, 0.5f));
+          Box rect = new Box(plane.getExtentX() / 2, 0.005f, plane.getExtentZ() / 2, ap);
+          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);
+          ground.updateBody(rectObj);
         }
       }
 
@@ -453,14 +488,36 @@
           try {
             Object3D andy = ModelFactory.loadModel(getResources(), "models/andy.obj", null).createObject();
             andy.setPosition(new Position3D(px, py + 0.2, pz));
-            Solid3D andyObj = new Solid3D(andy);
+            OvergroundActor andyObj = new OvergroundActor(andy, null) {
+                public void onIntersect(CollisionResult cr, long interval) {
+                    // めり込んだら（めり込んだ面の法線方向に）押し戻す
+                    Vector3d back = (Vector3d) cr.normal.clone();
+                    back.scale(cr.length * 2.0);
+                    body.apply(new Position3D(body.getPosition3D().add(back)), false);
+
+                    // 速度の面の法線方向の成分を 0 にする
+                    Vector3d v = (Vector3d) ((Solid3D)body).getVelocity().getVector3d().clone();
+                    double d = v.dot(cr.normal);
+                    v.scaleAdd(-d * 1.5, cr.normal, v);
+                    body.apply(new Velocity3D(v), false);
+                }
+            };
+//            Solid3D andyObj = new Solid3D(andy);
             universe.place(andyObj);
-            physicalSystem.add(andyObj);
+//            physicalSystem.add(andyObj);
           } catch (IOException e) {
             e.printStackTrace();
           } catch (ModelFileFormatException e) {
             e.printStackTrace();
           }
+//            Box b1 = new Box(1.0f, 1.0f, 1.0f, null);
+//            Object3D obj1 = new Object3D("box", b1);
+//            obj1.apply(new Position3D(px , py + 0.3, pz), false);
+//            Solid3D diceObj = new Solid3D(obj1);
+//            diceObj.scale(0.01, 0.01, 0.01);
+//            diceObj.setMass(250);
+//            universe.place(diceObj);
+//            physicalSystem.add(diceObj);
           anchors.add(anchor);
           break;
         }
@@ -477,4 +534,17 @@
     }
     return false;
   }
+
+  public static float calculateDistanceToPlane(Pose planePose, Pose cameraPose) {
+    float[] normal = new float[3];
+    float cameraX = cameraPose.tx();
+    float cameraY = cameraPose.ty();
+    float cameraZ = cameraPose.tz();
+    // Get transformed Y axis of plane's coordinate system.
+    planePose.getTransformedAxis(1, 1.0f, normal, 0);
+    // Compute dot product of plane's normal with vector from camera to plane center.
+    return (cameraX - planePose.tx()) * normal[0]
+            + (cameraY - planePose.ty()) * normal[1]
+            + (cameraZ - planePose.tz()) * normal[2];
+  }
 }