var entity = viewer.entities.add({
    name : url,
    position : position,
    orientation : orientation,
    model : {
      uri : url,
      minimumPixelSize : 128,
      maximumScale : 20000
    },
    description:"\<div>与infobox关联的提示信息在description属性中设置</div>\<div>可添加html标签，斜杠开头</div>"
  });viewer.trackedEntity = entity;

},