All Questions
45,270
questions
0
votes
1
answer
91
views
rviz2 does not display an urdf file
Hello everyone, I have a question related to rviz2. I am trying to display an urdf and rviz2 show this:
I got the tf but I can't represent the 3D models.
Thank you
Originally posted by jarain78 on ...
1
vote
2
answers
666
views
Some doubts regarding SLAM and its technical terms
I have some questions regarding SLAM and some general technical terms used in the context of it.
Q1) **Online SLAM vs Offline SLAM**. Can "Online" SLAM be also called "real-time" SLAM? What is the ...
0
votes
1
answer
21
views
Topic Advertise Conflict: md5sum and Datatype Mismatch
Hi everyone,
I have been trying to set a GPS position by setting mavros/setpoint_position/global, but faced with this error message:
...
0
votes
2
answers
62
views
ROS2 prioritize Wifi over Ethernet by default? (Whitelist Interface)
Ubuntu 20.04, ROS2 Foxy
Binary installation, FastRTPS (Default)
I was setting up multiple machines using ROS2 Foxy.
PC 1 and PC 2:
Ethernet with static IP address
Wifi with DHCP
PC 1 and PC 2 are ...
0
votes
1
answer
253
views
Connect LiPo battery to Arduino Motor Driver Shield for RC Boat
Thanks for taking the time reading this question! It is greatly appreciated.
What are we doing
We (two complete noobs) are building a remote controlled boat from scratch using Arduino compatible ...
0
votes
1
answer
2
views
Ros Installation Win10 | rosout.exe not in directory
Hello Guys,
i installed ROS Melodic on Win10. Now when i run "roscore" the following error is displayed to me:
...
0
votes
1
answer
252
views
libstatistics_collector: Unknown CMake command "rosidl_get_typesupport_target" (galactic)
Hello everyone,
I am trying to build ROS2 from source following the galactic link. While building, I am getting the below error,
...
0
votes
1
answer
166
views
Off the shelf way to power jetson nano and xavier from iRobot Create 2
I'm making an indoor companion bot, but requirement is that it easily traverse thick carpet, which is common all across the US in houses. Seems no better platform than 'Roomba' which was designed for ...
0
votes
1
answer
1
view
How do you edit the collison like this?
Here is the picture:
I edited the code many time:
...
0
votes
1
answer
32
views
Generic question about the error "Waiting for service /gazebo/spawn_urdf_model"
Hello,
I had a generic question about a specific error.
It says Waiting for service /gazebo/spawn_urdf_model and the terminal freezes. This usually happens when I'...
0
votes
1
answer
14
views
Action Server Compiler Error => error: no match for call to ‘(boost::_mfi
Hi all,
I have a problem about creating an action_server on ROS1. I have created a few action server programs in the past. But never get this error which i will tell the details of. My action server ...
0
votes
2
answers
30
views
Is the translational vector (positon) in transformation matrices in cm or another unit (MATLAB)?
My transformation matrix gives me, for example, x = 0.06, y = 0.27 and z = -0.04
It does not make a lot of sense to me if this is in cm.
0
votes
1
answer
62
views
Count number of collisions while navigating to goal
I have the navigation stack working in ROS Kinetic on my computer. In Stage ROS simulations, I can specify the goal and the robot navigates to it. I need to count the number of collisions (if any) ...
0
votes
1
answer
1
view
Getting direction from single universal laser
I have 360 degrees laser coverage around a robot with the data published into a single topic. But because of that I can not tell what laser data reflects right, left, front or back or the robot.
Just ...
0
votes
1
answer
2
views
Why is the model "head" kept falling down through the another model "chassis"?
the code is here:
...
0
votes
1
answer
2
views
costmaps being updated with data from two sensors of different heights
Hi
I have a robot with an RPLidar sensor on top and would like to add an ultrasonic sensor to identify and avoid obstacles that are below the LIDAR line. It is possible?
My robot:
Let's say the ...
2
votes
1
answer
148
views
Proper implementation of `pure_pursuit` for ground robots using waypoints
I am trying to understand and implement pure-pursuit waypoint following in 2D map. My questions are:
1. What exactly do I need to record in my waypoint.csv file?
To ...
0
votes
2
answers
17
views
[ros2_control] Combined hw_interface for arm and gripper
We have a robot that's a little unusual in that the manufacturer combined gripper control and arm joint control into a single, unified API. Thus, we can't really instantiate 2 objects to control ...
4
votes
1
answer
224
views
Why does a motor does not run when a resistor is connected in series between the supply?
I decided to remove the battery (1.6 V 1600 mAh) from my trimmer and to power it via an old mobile charging cable (6 V 800 mAh).
So I built a voltage divider circuit, which gave me nearly 1.6 V but ...
0
votes
1
answer
15
views
move base for omni?
Hello i am trying to control the omni or mechanum wheels with the move base for autonomous navigation. But as i saw that move base only suppports the diff drive wheels.
Is it possible to use move base ...
0
votes
1
answer
71
views
proper guide to adding a gripper to my robot in rviz2 and moveit2
im currently running ros2 on foxy and using this driver for the UR10e https://github.com/UniversalRobots/Universal_Robots_ROS2_Driver/ which works perfectly fine, but now im trying to add a gripper to ...
0
votes
2
answers
44
views
LaserScan rotates when moving
I'm new to ROS, and picked up a robot that used to be able to perform SLAM with gmapping. I'm working on getting it up and running after years of sitting in a lab, but I can't get the robot to map or ...
1
vote
2
answers
114
views
Reflective surface
Have you encountered the problem of reflective surfaces for realsense camera (d435 or t265) and lidar (A1 or A2). I would like to know what are the ways to solve problems with reflective surfaces for ...
0
votes
1
answer
9
views
Get message published before subscriber start
Hello,
I have a publisher node set to publish only once a message right after it started.
I have a subscriber node that subscribes to this topic but that is sometimes started a little time after the ...
0
votes
1
answer
142
views
Publish Float64MultiArray from command line - ROS2
I can't seem to figure this out:
ros2 topic pub /gripper_controller/commands std_msgs/msg/Float64MultiArray lay [TAB COMPLETE]
Now the message is auto-populated ...
0
votes
2
answers
3
views
What is first ? Publisher or Subscriber?
Which among the following nodes should be started first? Publisher or Subscriber.
What happens if start subscriber first then publisher?
Note: Subscriber is working as intended (printing the received ...
0
votes
1
answer
3
views
Autoware: How to run ndt_gpu on the platform of Xavier NX
The newest version of master branch code which needs the cuda version is <=10.0. But Xavier NX's cuda version is 10.2.
And I have tested the ndt_gpu on my PC(rtx 1050ti, ubuntu 18.04, eigen 3.3.9), ...
3
votes
1
answer
281
views
Unstable principal point estimation in zoom camera calibration
I have a camera with a 1/2.9" image sensor from FLIR and a 12-50mm motorized zoom lens from Theia. Because the lens is a motorized zoom lens, I tried to calibrate the camera for different zoom ...
0
votes
1
answer
27
views
What is the naming conventions for tf_prefix vs ns?
I have not found a clear answer to this, and reading code on Github has merely confused things further.
What is the standard naming convention for tf_trees that relate to a namespace for a robot? ...
0
votes
1
answer
35
views
bt_navigator failing with error `Action server failed while executing action callback: "send_goal failed"`
I am using
ROS2 Foxy
Nav2 for navigation
Slam-toolbox for mapping and localization
create_robot for odom
When I send a command to the ActionService ...
0
votes
1
answer
214
views
Rospy: Why does the loop not get interrupted?
I am working on the software for an autonomous Raspberry-Pi based robot which should keep moving for 2 minutes unless an unintended key is fed to it as input. Upon receipt of the unintended key, the ...
0
votes
1
answer
1
view
Problem with assigning different colors to segments in PointCloud
Hello,
I am trying a segment tracking algorithm. Right now I have 2 segments. I am coloring each segment with different RGB values, pushing the segments into output_cloud which is pcl::PointCloud2pcl::...
1
vote
1
answer
42
views
Affordable pi like computer for robot
I have raspberry pi in a robot but it seems sdcard is not reliable at all.
What are affordable options that could be considered reliable? Pi+USB Flash, Pi+USB SSD, Pi compute module with eMMC, ...
0
votes
1
answer
19
views
Do I have to source both ros2_galactic/install/setup.bash and /opt/ros/galactic/setup.bash?
TLDR:
Even with a source based install of ROS2, running rosdep will install libraries into /opt/ros/galactic/. To have all packages available in every terminal I ...
0
votes
1
answer
21
views
Can't build with roslaunch as a dependency
I've been given a repo with roslaunch as a dependency in the CMake files, and it fails to build like so:
...
1
vote
1
answer
1k
views
Forward/inverse kinematics and transformation matrices
I have found the homogeneous transformation matrix that can be used to determine the relation between the parent and child links of a robot. This matrix is shown below.
$T_i =
\left[\begin{array}{ c ...
0
votes
1
answer
9
views
DWA Planner path deflects and prevents smooth movement
Hi, here's the video. Problem occurs at 0:09 and 0:17. When i give goal to the robot, DWA planner produces local path but, after the robot gains good velocity, it produces a local path which greatly ...
0
votes
1
answer
116
views
Why need joint state and robot state publishers?
I’m learning ROS2 with Foxy and a GoPiGo3 robot. I have built a working ROS2 gopigo3_node on my Raspberry Pi based robot (Ubuntu 20.04) Server, and a basic URDF representation of the body, castor ...
0
votes
1
answer
335
views
Epson RC+ line numbers
I am programming an EPSON SCARA robot using RC+ 7.4.8. Any error in compiling the program shows in red in the bottom status bar with the error message, program and line number.
This would be wonderful ...
0
votes
1
answer
6
views
simpleActionClient not connecting to simpleActionServer on seperate computers
This is on two machines both running ROS Noetic on Ubuntu20.04, done with rospy
I have a remote machine, which is running roscore. It will run a node which starts an action server. Here is how I start ...
4
votes
1
answer
266
views
How to perform decoupling between decision making and action execution in ROS2?
Hi I'm making a robot using:
ros2 foxy
OS Ubuntu Linux 20.04.2 LTS (Focal Fossa).
Linux 5.8.0-59-generic
I built an Action based on the tutorial Building an Action Server and Client. Then expanded ...
0
votes
1
answer
40
views
No transition matching 3 found for current state
I'm looking at the ros2 lifecycles demo here: https://github.com/ros2/demos/blob/foxy/lifecycle/src/lifecycle_talker.cpp
According to the Lifecycles page of ROS2 if an exception occurs in any of the ...
0
votes
1
answer
2
views
no messages received in topic after transformation
Hello,
we are driving a vehicle with GPS and automated path planning and I recorded the drives.
The rosbag is playing great, but I wanted to visualize the driven path to check the accuracy.
I tried ...
0
votes
1
answer
578
views
Can someone explain this yaw angle calculation equation?
Nowdays, I am trying to understand PX4 Autopilot(Drone Flight Control Open Source) attitude control code. But I can’t understand formula below which is in attitude control code description.
Can anyone ...
0
votes
1
answer
4
views
CFG_EXTRAS equivalent for ros2/colcon
We have a ROS1 CMakeLists.txt that contains:
...
0
votes
1
answer
118
views
How to use STM32 IDE with microROS + FreeRTOS?
As the title says. How do I incorporate the STM32 IDE into my development workflow? Alternatively, is there a suggested development workflow that is better?
Originally posted by Bhavesh on ROS ...
0
votes
1
answer
18
views
SyntaxError: invalid syntax for roscore
I tried to install relaunch roscore on Ubuntu 18.04 but got the following error. Any advice is greatly appreciated.
...
2
votes
2
answers
625
views
GPS+IMU sensor fusion not based on Kalman Filters
Do you know any papers on or implementations of GPS + IMU sensor fusion for localization that are not based on an EKF (Extended Kalman Filter) or UKF (Unscented Kalman Filter)?
I'm asking is because
...
0
votes
1
answer
8
views
how to inflate STVL's obstacles
Now I'm using Spatio Temporal Voxel Layer in my ROS Navigation.I find that the obstacles STVL detected do not have inflation. I notice that obstacle layer's obstacle have inflation. I don't know where ...
0
votes
1
answer
55
views
ROS2 Publish and subscribe in same node
I am trying below code where I have a ROS2 foxy node that first publishes camera frames to a topic camera_frame and then is supposed to be listening to another topic drive_topic. I have created a ...