ROS Programming: Building Powerful Robots

Creating the laser node

Now we will create a new file in chapter5_tutorials/src with the name laser.cpp and put the following code in it:

#include <ros/ros.h> 
#include <sensor_msgs/LaserScan.h> 
 
int main(int argc, char** argv){ 
  ros::init(argc, argv, "laser_scan_publisher"); 
   
  ros::NodeHandle n; 
  ros::Publisher scan_pub = n.advertise<sensor_ msgs::LaserScan>("scan", 50); unsigned int num_readings = 100; double laser_frequency = 40; double ranges[num_readings]; double intensities[num_readings]; int count = 0; ros::Rate r(1.0); while(n.ok()){ //generate some fake data for our laser scan for(unsigned int i = 0; i < num_readings; ++i){ ranges[i] = count; intensities[i] = 100 + count; } ros::Time scan_time = ros::Time::now(); //populate the LaserScan ...