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Why is ROS1 Message Generation Slow in Python?

I hit a performance issue when trying to use a custom message type in ROS 1 Noetic in Python. My custom message was defined like this: ...
Marc Micatka's user avatar
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In MicroROS/Agent Is there a message size limit when both the Pub/Sub are MicroROS node

Note: This is a repost from the Slack channel I am trying to send a CompressedImage type from a camera node to an LCD Node and it appears that I am sending messages, but the callback on the ...
John Gentilin's user avatar
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ROS2 colcon build error MSB8066: ModuleNotFoundError: No module named 'rosidl_generator_cs'

Using ros2cs, I am trying to build a package in Windows that includes a custom message type and eventually a service, for use in a C# solution aided by rclnet. But executing this from the Visual ...
Eric Eggers's user avatar
1 vote
1 answer
46 views

Publish an Array of Values as Wrench Message in ROS2 and Python

I'm using a geometry wrench message, and I would like to send 4 values at each force and torque axis. I tried something like this: ...
Mohamed Abduljawad's user avatar
1 vote
1 answer
122 views

KeyError:'unique_identifier_msgs' and KeyError:'service_msgs' when compiling interface package

I am pretty new to ROS, so please do not expect much from me. I am building a robotic system for my project, and as of right now I am setting up interfaces to use in the project. I added a message ...
highjeans 's user avatar
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1 answer
14 views

LaserScan scan_time for multiple scans in a single rotation

I have a LiDAR device that reports the entire 360 degree range, but split into scans of 22.5 degrees each, and I'm trying to assemble my LaserScan messages correctly. As I understand, each 22.5 scan (...
Caian's user avatar
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0 answers
16 views

My ros topic can't echo any info

My code of node is following ...
young very's user avatar
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1 answer
97 views

Is there a way to enumerate over predefined constants in ROS2 message definitions?

I'd like to know if there is a way to enumerate over the available constants defined in a message. As an example, let's take the visualization_msgs/Marker.msg as an ...
Steve's user avatar
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1 answer
543 views

How to add a header with timestamp to numpy_msg?

I am using the rospy with numpy tutorial to create a publisher and subscriber that send numpy arrays to listener that uses an ApproximateTimeSynchronizer. However, I receive an error when I try to ...
BeginnersMindTruly's user avatar
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1 answer
24 views

Message with array of data

Hello everyone, I try to create a custom message containing an array of int8. Therefore I use the .msg-file int8 len int8[] data and when I run colcon everything ...
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1 answer
2 views

can't import custum message in python

...
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0 votes
1 answer
35 views

Rosserial Arduino custom message not being generated

I have made a custom message called gas_msg.msg. It is located in a package named gas_sensor_msg. The custom message has been created with catkin_make. I am now trying to make the custom message files ...
user avatar
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1 answer
3 views

Custom action message can't be found during compilation

So I created a custom action message, under the laser_line_extraction/action folder: CornerExtractionAction.action: ...
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2 answers
12 views

if the required message is a standard message type available with ROS, do we still need to define it in msg/xxxx.msg?

If my message type is geometry_msgs/WrenchStamped, do I still need to define it in msg folder or I can skip it? As I am not using a custom message type. Thanks Anirudh Originally posted by ...
user avatar
0 votes
1 answer
46 views

Read /rosout/msg with seperate Python script

Hello! I am currently working on a project where I navigate a TurtleBot3 to several positions in a room. The TB3 navigation is triggered by publishing messages to a specific topic (/tb3_hsc/command). ...
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1 answer
5 views

Problem with Action msg

Hello, I wrote my own Action msg for ROS. This is the msg : #goal string start_phrase --- #result point coordinates --- #feedback duration time_elapsed This is my ...
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0 votes
1 answer
249 views

Best way to save ROS 2 topic messages to text file in Python callback?

I would like to save a ROS 2 topic message into a text file in a Python callback. I can use a csv.DictWriter if I first convert the message into a dictionary. Is there a better way of converting a ...
user avatar
0 votes
1 answer
14 views

error getMD5Sum in customized message type

Hi everyone, I am a newbie trying to create a customized message type but it always ends up with this error. I will appreciate greatly if someone can help out. I spent hours on this and don't know ...
user avatar
0 votes
1 answer
6 views

How to plot a message bool in a bag file?

A lot of times there's a bool in a message which qualifies analog data in the message; e.g. nav_data_valid or is_stopped, and which needs to be viewed to understand node behavior. I know I can look at ...
user avatar
0 votes
1 answer
4 views

Implement custom message in Android Studio

Hello, at the moment I am developing an Android application that publishes data into a ROS environment. For this, I use rosandroid-core which is included with Maven from the following repository: ...
user avatar
0 votes
1 answer
3 views

Callbackfunction is not called even though messages are published

Hey there, I am using Ros kinetic on Linux and have used cpp nodes so far. Now I added a python node which should publish a message to a cpp node. During debugging I found out the following. My cpp ...
user avatar
0 votes
1 answer
78 views

rospy.wait_for_message is unable to subscribe to a message

rospy.wait_for_message can receive one message from topic. It will create a new subscription to the topic, receive one message, then unsubscribe. But when I try to use it, the function can't work at ...
user avatar
0 votes
1 answer
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how to calculate difference of two messages in callback function on same topic

Hi Sir, I am actually reading my hand pose from a Leap Motion sensor and I want to calculate how much the hand moves in X direction. My question is how to read the message in callback function(as you ...
user avatar
0 votes
1 answer
67 views

How to publish a dictionary with other dictionary inside in a topic?

Hi all, I'm trying to publish in a topic a dictionary with other dictionary inside so other ROS node is able to access to that information, but I do not know how can I do it. Anyone has any idea? ...
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0 votes
1 answer
6 views

Print subset of message

I would like to programmatically print a subset of this message, specifically only the flags set to true. I have found only this question regarding the display of messages, and the answer suggests to ...
user avatar
0 votes
2 answers
19 views

Initialize constant message

How do I initialize a constant message (with 2+ fields) in a class constructor? This is more of a raw C++ question but intertwined with some ROS complications. Some background: for the class I'm ...
user avatar
0 votes
1 answer
22 views

How to check size of a topic on multi device ROS Communication

Hello, experts. I am trying to ROS communicate with multi device. There is two PC. First one have a camera sensor, it have publish topics by 30 fps. Second one have be connected to another by 1Gb ...
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0 votes
1 answer
5 views

Issue with Rosserial Custom Message

I am using ROS Kinetic on Ubuntu 16.04. I've been trying to get a custom message type to work over rosserial_arduino for some time now. I have properly generated the C++ message headers in the package....
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0 votes
2 answers
25 views

Can ROS messages be exchanged between a nonROS machine?

Currently i am working with ROS2 which is based on DDS. So I have ROS2 installed on 1 machine and on the other I have a DDS implementation. So basically I can exchange messages through DDS and I do ...
user avatar
0 votes
1 answer
24 views

rosbag : rewrite the values of a topic

Dear all, what can be the best way to rewrite the values of the messages in a topic in a bag file. For instance, how can I go about creating a new bag that contains modified values of a topic of ...
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0 votes
1 answer
7 views

Why do we need to add generators for messages, services and actions, but only generate messages (in the CMakeLists.txt file)?

In the following article http://wiki.ros.org/catkin/CMakeLists.txt#Overall_Structure_and_Ordering, it is stated that, for a package to be correctly built, we must follow a certain format for the ...
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0 votes
1 answer
14 views

How to get the message from the Subscriber Function

Hi, I am relatively new to ROS and have a question regarding Publisher and Subscriber. To make this easy I use the Code from the ROS Tutorial "Writing a Simple Publisher and Subscriber (C++)&...
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0 votes
1 answer
228 views

Are ROS2 messages guaranteed to be received by a Subscriber in the same order they were published?

According to https://github.com/ros2/ros2/wiki/About-Quality-of-Service-Settings it's possible to vary the QoS settings of History, Depth, Reliability and Durability. However, I can't find any mention ...
user avatar
0 votes
1 answer
3 views

Convert coordinates to a ROS Message

Hello, I have the task to write a program (C++) to convert the coordinates (x, y, z) into a ROS Message. I have read the coordinates and stored them in array. Now i have convert these coordinates into ...
user avatar
0 votes
1 answer
79 views

ImportError: No module named msg

I have googled a lot of solutions, but none have worked. I follow exactly the same as http://wiki.ros.org/ROS/Tutorials/CreatingMsgAndSrv#Creating_a_msg. Is there anything I missed? my python script <...
user avatar
0 votes
1 answer
2 views

Simple Command to robot fails

I have a problem writing a simple node that publishes messages of a type called JointVelocity which has 2 objects called velocity of the type JointQuantity and ...
user avatar
0 votes
1 answer
7 views

Rospy callback attribute error

Am following a youtube tutorial (https://www.youtube.com/watch?v=DLVyc9hOvk8) with my own code: Executable: ...
user avatar
0 votes
1 answer
4 views

Subscribe Message file

Hello! I want to subscribe data from .msg file. However the file has four other msgs inside. The format of the .msg file is: ...
user avatar
0 votes
1 answer
11 views

How to write a node in iOS?

I want to write a iPhone app that's able to publish some message on a ROS topic. I found one implemented with RabbitMQ from here : https://github.com/tomas789/iOSmsg_client. However, I would prefer ...
user avatar
0 votes
1 answer
8 views

Where is the message definition stored?

When a topic is advertised, are the md5 and the message definition of that message type stored somewhere accessible on the Ros server (By another node) or are they only sent with the message itself ...
user avatar
0 votes
1 answer
1 view

puclish messeage to arduino

Hi , I'm trying to move robot using ROS & arduino. I confirmed message "twist_cmd" published using echo but I don't know how to send the message to arduino. Please tell me. Originally ...
user avatar
0 votes
1 answer
11 views

How to really blink an LED on an arduino through ROS

I set up ROS with an arduino and successfully implemented the blink-example. However, I would like to really make it blink, e.g. to turn the LED on and off with a high frequency. Unfortunately, I have ...
user avatar
0 votes
1 answer
7 views

How to pull a message from queue with time interval?

When I subscribe my node, I set messages queue size and callback function: ...
user avatar
0 votes
1 answer
4 views

how to publish a complex msg via launch file?

I set a msg named NavigationPoint and its definition is that: std_msgs/Header header geometry_msgs/Pose pose time arrival_time int32 formation int32[] parameters. ...
user avatar
0 votes
1 answer
3 views

What message to use to publish the position of a rover

Hi, I a newbie here. I've been trying to understand the appropriate message to use when publishing the position of a rover on a map. I have a topic of a "chassis" which I want to use to ...
user avatar
0 votes
1 answer
7 views

Transfer octomap w/out ROS Message

Hey guys, is there a way to transfer a octomap between two nodes without using ROS messages? Due to high processing time I sourced out the octomap creating - and need the processed octomap in my main ...
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0 votes
1 answer
1 view

ROS .msg depends

I have two packages: inpub and insub in inpub CmakeList.txt ...
user avatar
0 votes
1 answer
58 views

Access all the fields in ROS msg

This is probably a very simple and stupid question, but I searched everywhere, and maybe because it's so simple I can't find an answer. I created a msg like this (and maybe Im gonna add a string later ...
user avatar
0 votes
2 answers
79 views

How would I publish a 2D float Array through a ROS message?

I am currently working on a circle detection app. Using OpenCV, I get a std::vector<std::vector<float>> named ...
user avatar
0 votes
1 answer
23 views

Arduino /cmd_vel and /odom with Pololu motors w/ encoder

Hi guys, I have been struggling with my robot for 3-4 days now. I want to publish to the /cmd_vel topic and then to the /odom topic using the Arduino MEGA connected to 4 Pololu motors with encoders. I ...
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