Change
CollisionShape shape = CollisionShapeFactory.createMeshShape(buggy);
to
CollisionShape shape = CollisionShapeFactory.createDynamicMeshShape(buggy);
to see if it will fix
Please see this thread
Change
CollisionShape shape = CollisionShapeFactory.createMeshShape(buggy);
to
CollisionShape shape = CollisionShapeFactory.createDynamicMeshShape(buggy);
to see if it will fix
Please see this thread