thailor3's profile - activity

Yes, the magnitude I have written here is correct. Fifty thousand vs ten point zero. It is ROS indigo.

I am doing a rosservice call to a trigger camera exposure rate of a basler pylon camera... and I set the exposure rate to 50,000 or more each time... and I keep getting an exception saying:

"Exception thrown while processing servic ecall: Value 10.0000 must be greater than or equal 47.0000: OutOfRangeException thrown in node 'ExposureTimeAbs' while calling 'ExposureTimeAbs.SetValue( )'". 50,000 is way larger than 10.0000 so i don't understand why I get the error. but if i put in anything less than 47.0000, 45 for example, then the error reads 'Value 45.0000 must be greater than or equal 47.0000'. In my own created node, there is no comparison to 47 at all that I can see, and I cant seem to find that in the pylon camera code either.

anyone had this problem before or have any ideas why it is happening?

Getting started with Visual Studio, follow this link, good luck mate

https://msdn.microsoft.com/en-us/libr...

Does anyone know if there is an equivalent of the console command "rosparam get 'parameter'" or "rosparam list" that can be written in to a .launch file. Wanting to check if a parameter is set or exists. So i was thinking that I could use an unless or if check but I don't know how to tell it to check if it exists in the parameter server... Please someone help hahaha

basically I'm trying to say that if the value passed to the cam_serial argument by the user is "21665943" then do not launch...so how should i change my launch file?

Running this file with roslaunch command, and passing the cam_serial and cam_index. But I'm getting error: Invalid roslaunch XML syntax: unbound prefix: line 3, column 0 The traceback for the exception was written to the log file

What is wrong?

<?xml version="1.0"?>
<launch>
   <xacro:property name="cam_serial" value="$(arg cam_serial)"/>
   <xacro:unless value="<21665943>">
   <
   <!-- Essential camera parameters -->
   <arg name="cam_serial"/>
   <arg name="cam_index"/>

   <!-- AOI Settings -->
   <arg name="aoi_width"  default="960" />
   <arg name="aoi_height" default="540" />
   <arg name="aoi_pos_x"  default="480" />
   <arg name="aoi_pos_y"  default="270" />

   <!-- Color calibration -->
   <arg name="red_gain" default="1.0" />
   <arg name="green_gain" default="1.09375" />
   <arg name="blue_gain" default="2.21075" />

   <!-- Additional parameters -->
   <arg name="auto_white_balance" default="false" />
   <arg name="bandwidth_limit" default="8000000" />
   <arg name="zoom" default="1" />
   <arg name="reverse_x"  default="false" />
   <arg name="reverse_y"  default="false" />

   <group ns="image$(arg cam_index)">
       <node name="cam$(arg cam_index)" pkg="basler" type="camera" respawn="true" respawn_delay="10"           output="screen">

          <!-- Some default parameters that probably don't need to be changed -->
          <param name="auto_exposure" value="false"/>
          <param name="auto_gain" value="false"/>
          <param name="gain" value="1.0"/>
          <param name="cam_serial" value="$(arg cam_serial)" unless="true"/>
          <param name="hardware_gamma" value="true" />
          <param name="frame_rate" value="1.0"/>
          <param name="exposure_time" value="25000.0"/>

          <!-- These parameters will probably be changed-->
          <param name="aoi_width"  value="$(arg aoi_width)" />
          <param name="aoi_height" value="$(arg aoi_height)" />
          <param name="aoi_pos_x"  value="$(arg aoi_pos_x)" />
          <param name="aoi_pos_y"  value="$(arg aoi_pos_y)" />
          <param name="zoom"       value="$(arg zoom)" />
          <param name="reverse_x" value="$(arg reverse_x)"/>
          <param name="reverse_y" value="$(arg reverse_y)"/>
          <param name="red_gain" value="$(arg red_gain)" />
          <param name="green_gain" value="$(arg green_gain)" />
          <param name="blue_gain" value="$(arg blue_gain)" />
          <param name="auto_white_balance" value="$(arg auto_white_balance)" /> 

          <!-- Remap trigger service and output topic -->
          <remap from="image_raw" to="raw"/>
          <remap from="trigger_camera" to="trigger_camera"/>
       </node>
    </group>
    >
 </xacro:unless>
 </launch>

I have a launch file that takes a serial number and a index number and launches the node based on those numbers, however if I launch one node with a serial number, and then a second node with the same serial number, then the second node will cause the first to shutdown because of "ros node with same name" and then since I have my respawn set to true (for other reasons) then the first node respawns and shutsdown node 2, and etc etc.

Any ideas how i can check for the serial number already being used? assuming the user is completely ignorant to any node already launched. I wanted to ideally check in the launch file, but I can only do boolean expressions with the "if" or "unless" statements, and for what I am trying, it doesnt work. PLEASE HELP!XD Thanks

perhaps there is an xarco type statement I can write? I am just not extremely familiar with it.

I want to cancel the creation of a node in the launch file if a value, which is entered by user in console, equals a certain value. For instance

I am launching a file: roslaunch file attr1:='1' attr2:='2'

and in my launch file i want to do a check. the syntax in any other language would be :

if (attr1 == value){ cancel node};

problem is, in the launch file I tried to use a unless="$(arg attr1)" but it's not a bool because when i enter the value in the console, it is an int. So i realized the unless and if conditionals in the launch file are explicitly looking for a true or false, and that they can't do a comparison:

unless="$(arg attr1 == '1')"

did not work. any suggestions? Any syntax I can use launch file that would make this work?

THANKS!

so in order to get any node's param on the rosparam server, then i can do getParam()? for instance if i have the list of params: /image1/cam1/1 /image1/cam1/2 /image2/cam2/1 /image2/cam2/2

and i am launching another node that will spawn the paramters /image3/cam3/1, i do getParam("/image1/cam1/1")?

Example: I have always the same node type, lets say with a parameter named "shape"

I make one node (node A) with shape = "square"

I make a second node (node B) with shape = "circle"

in the console if i did rosparam list i would see /nodeA/shape /nodeB/shape

and if i did rosparam get /nodeA/shape i would see "Square", but is it possible in my test file, my cpp file, to use some form of get parameter when creating a node, so that I can see that node A shape is "Square"? pseudocode:

    if(&newNode/shape == &nodeA/shape)
              kill(newNode, SIGINT)

Overall, i want to be able to test and see if a value of the parameter exists, and then if it exists, i will do a kill(pid, SIGINT).

But i am having a hard time accessing the parameter value of the other nodes.