ROS query topic specific content common instructions

Poor memory always forgets ros Query the specific content of the topic , Now take notes , If you don't remember, just turn to the blog .

One .

$rostopic list

Output

/scan 

Two .

$rostopic info /scan 

  Output

Type: sensor_msgs/LaserScan

Publishers: 
 * /play_1599208623127841919 (http://lzm:40267/)

Subscribers: None

3、 ... and .

$rosmsg  show  sensor_msgs/LaserScan

Output

std_msgs/Header header
  uint32 seq
  time stamp
  string frame_id
float32 angle_min
float32 angle_max
float32 angle_increment
float32 time_increment
float32 scan_time
float32 range_min
float32 range_max
float32[] ranges
float32[] intensities

Four .

$rostopic echo /scan -n1

  Output

header: 
  seq: 11949
  stamp: 
    secs: 1541936147
    nsecs: 883302943
  frame_id: "laser_link"
angle_min: 0.0
angle_max: 6.27445888519
angle_increment: 0.00872664619237
time_increment: 0.000272695964668
scan_time: 0.109351083636
range_min: 0.0799999982119
range_max: 15.0
ranges: [8.829999923706055, 8.756999969482422, 0.0, 9.017999649047852, 0.0, 8.987000465393066, 0.0, 9.060999870300293, 0.0, 0.0, 0.0, 0.0, 9.119999885559082, 0.0, 9.17199993133545, 0.0, 8.293999671936035, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, ........]