I need to collect the point cloud data from many sensors (the number of sensors isn't fixed) together with the position of the robotic arm. Below is the information about ros message types-

1. baxtercoremsgs::EndpointState
2. sensor_msgs::PointCloud2

In short, I want get data from *single** baxter_core_msgs::EndpointState and multiple sensor_msgs::PointCloud2 simultaneously.*

I am trying to use Chain filter. Below is the code snippet-

void ChainFilterTest::myCallback(const MsgConstPtr& msg)
{
  ROS_INFO("Callback received");
}

ChainFilterTest::ChainFilterTest()
{
  ros::NodeHandle nh("~");

  message_filters::Chain c;
  c.addFilter(boost::shared_ptr<message_filters::Subscriber<baxter_core_msgs::EndpointState> >(new message_filters::Subscriber<baxter_core_msgs::EndpointState>(nh, ee_topic, 1)));

  std::string pc_topics[] = {"pc_topic_1", "pc_topic_2"}; // the number of elements aren't fixed
  int length = sizeof(pc_topics)/sizeof(pc_topics[0]);
  for(int i = 0; i < length; i++ )
    c.addFilter(boost::shared_ptr<message_filters::Subscriber<sensor_msgs::PointCloud2> >(new message_filters::Subscriber<sensor_msgs::PointCloud2>(nh, pc_topics[i], 1)));

  c.registerCallback(&ChainFilterTest::myCallback, this);
  ros::spin();
}

Above code shows following errors during complication-

error: ‘MsgConstPtr’ does not name a type
 void ChainFilterTest::myCallback(const MsgConstPtr& msg)
                                      ^
error: missing template arguments before ‘c’
     message_filters::Chain c;
                            ^
error: ‘c’ was not declared in this scope
     c.addFilter(boost::shared_ptr<message_filters::Subscriber<baxter_core_msgs::EndpointState> >(new message_filters::Subscriber<baxter_core_msgs::EndpointState>(nh, ee_topic, 1)));
     ^

The first error is related to the declaration of the message type. The second error is also similar. The message type isn't same across all filters.

I want to know that how to use Chain filter in this situation?