Extract specific Data from topic
Hello there,
I have a node in ros publshing data of type Measurement2 which is used for RN Sensors. The problem wit the Datatype is that it publishes several different Values like you can see here:
header:
seq: 36
stamp:
secs: 1531906243
nsecs: 20823955
frame_id: "wifi_adapter"
device_name: "simulated"
device_designation: "wifi_adapter"
classification: "W"
values:
-
sensor: "Elrob-RN-1"
source: "wifi signal strength"
type: "wifi signal strength"
value: [-30.0]
unit: "dBm"
min: 0.0
avg: 0.0
max: 0.0
alert_level: 0
alert_explanation: ''
substance: []
info: "Freq. 2.457 GHz mode: Master address: 08:EA:44:7A:FA:55 quality: 70/70 signal: -30.0"
I want to filter out the value of the signal and frequency from the broadcasted topic and then show it in rviz at the current position of my robot but I havent found a way yet how to extract the data and modify it so I can show it colorcoded on the created map in rviz
edit: thanks for editing the post to look better I somehow didnt get it to look straight
EDIT1:
My setup is a roboter with Laserscanners and RGBD Cameras to create a 2D and 3D map of its surroundings. Now I have to make something like a heatmap to show where strong signals occur on this generated maps. For this I need to extract specific Data from the topicoutput shown above. Especially i need the signalstrength and frequency data from the whole dataset.
Are you trying to build a map of wi-fi signal strength? So you're trying to extract the values->value element from the message?
Also you say 'the created map in rviz'. There are many ways of creating and showing maps in Rviz, can you describe the method you're using so we can give you some specific help.
Yes kinda, the wifi signal strength should simulate radioactive fallout and I need the values of the signalstrength and frequency extracted from the ti,opic to show on a 2D map in rviz