arduino sketch to subscribe to joint state msg

edit

I'm trying to use rosserial on arduino to subscribe to move_group/fake_controller_joint_states and then publish the first joints position on a topic chatter just to test verify that im receiving the position but it seems that the call back is not working as I don't seem to receive the values being sent on fake_controller_joint_states. Im using an arduino mega, kinetic and ubuntu 16.04. I greatly appreciate any direction or input. thank you.

#if (ARDUINO >= 100)
#include <Arduino.h>
#else
#include <WProgram.h>
#endif
#include <ros.h>
#include <std_msgs/Float64.h>
#include <sensor_msgs/JointState.h>
#include <stdlib.h>

ros::NodeHandle nh;
std_msgs::Float64 mydata;

float angle[6] = {0,0,0,0,0,0};

void cmd_cb(const sensor_msgs::JointState& cmd_arm)
{
  angle[0] = cmd_arm.position[0];
  angle[1] = cmd_arm.position[1];
  angle[2] = cmd_arm.position[2];
  angle[3] = cmd_arm.position[3];
  angle[4] = cmd_arm.position[4];
  angle[5] = cmd_arm.position[5];
}

ros::Subscriber<sensor_msgs::JointState> sub("/move_group/fake_controller_joint_states", cmd_cb);
ros::Publisher chatter("chatter", &mydata);

void setup()
{
  nh.initNode();
  nh.subscribe(sub);
  nh.advertise(chatter);
}

void loop()
{
  mydata.data = angle[1];
  chatter.publish( &mydata );
  nh.spinOnce();
  delay(1);
}

rostopic info /move_group/fake_controller_joint_states returns:

Type: sensor_msgs/JointState

Publishers: 
 * /move_group (http://chris-Latitude-3540:40629/)

Subscribers: 
 * /joint_state_publisher (http://chris-Latitude-3540:41687/)
 * /rostopic_5632_1530298559582 (http://chris-Latitude-3540:32869/)
 * /serial_node (http://chris-Latitude-3540:44431/)

rosnode info /serial_node returns:

Node [/serial_node]
Publications: 
 * /chatter [std_msgs/Float64]
 * /diagnostics [diagnostic_msgs/DiagnosticArray]
 * /rosout [rosgraph_msgs/Log]

Subscriptions: 
 * /move_group/fake_controller_joint_states [sensor_msgs/JointState]

Services: 
 * /serial_node/get_loggers
 * /serial_node/set_logger_level

contacting node http://chris-Latitude-3540:44431/ ...
Pid: 10725
Connections:
 * topic: /chatter
    * to: /rostopic_9634_1530306645550
    * direction: outbound
    * transport: TCPROS
 * topic: /rosout
    * to: /rosout
    * direction: outbound
    * transport: TCPROS
 * topic: /move_group/fake_controller_joint_states
    * to: /move_group (http://chris-Latitude-3540:40629/)
    * direction: inbound
    * transport: TCPROS