Terry Su's profile - activity

Hello ROS users,

I want to use a Non-ROS computer as the controller to receive the data from the ROS computer.

To specify my question : I have a lidar(sick tim 561) and I use my ROS computer(ubuntu 14.04 LTS with ROS Jade and a CAN card) to launch it successfully. After that, I have read the "Publisher and Subscriber" tutorials because I need use a subscriber to subscribe the lidar's scan topic and then transport the data to Non-ROS computer over the CAN-bus. But when I search the CAN-bus for the ROS for my ROS Jade version, I found this and without the JADE version. Does anyone know the CAN-bus communication for Jade? If there is the Jade version, could you direct me which part is I need? Thanks in advanced.

Hello ROS users,

Is there a possiblity to send Data through UDP from a ROS Node to the other non-ROS PC?

To specify my question : I have used the subscriber to subscribe the lidar's scan topic successfully,

and I want to pass the messages of the scanning data from my subscriber through the UDP protocol to the other one non-ROS computer.

I see this page regarding UDPROS but there seems to be little, new information.

Does anyone know or have used this before? I would be thankful if someone can direct me.

Hello ROS users,

I build a workspace folder which called jade_workspace in the home directory. In the jade_workspace folder, there are 3 files here which are the "setup.bash" , "setup.sh" , "setup.zsh", and I also create a folder here called sandbox.

In the sandbox, I want to create a package calls "beginner_tutorials", and I use the command as "roscreate-pkg beginner_tutorials std_msgs rospy roscpp" , after that, I use "rosmake beginner_tutorials" to build some data in this folder.

After that, because I run the example of "Creating a ROS Package" and "Writing a Simple Publisher and Subscriber (C++)", and I can run the talker and listener successfully in the example. I copy the file of "talker","listener" and "CMakeLists.txt" , "package.xml" to the jade_workspace's beginner_tutorials folder.

And after I source it and ran the talker, it shows the error as below: [rosrun] Couldn't find executable named talker below /home/terry/jade_workspace/sandbox/beginner_tutorials

Hello all of ROS users,

I want to use the gmapping to get the X,Y location data and track path data I followed the the website as follows to install it:http://wiki.ros.org/gmapping

But when I type the command "rosrun gmapping slam_gmapping scan:=base_scan" in the terminal, it shows

[rospack] Error: package 'gmapping' not found

Does anyone knows how to solve it? Thank you very much for your kindly help.

Hello,

I am a beginner of ROS system. Now I need to use it to receive and show the sick_tim561 lidar's datas, I already have installed the Ubuntu OS and Jade ROS. But I really don't have any idea about how to install of package as following link: http://wiki.ros.org/sick_tim I will be grateful if someone can kindly give me some direction. Thanks for your kindly help.

Hello ROS users, I am using a subscriber to subscribe lidar's signal. I have watched the subscriber and publisher example(C++) tutorial's video and use catkin_ws to build a package, and I make a sick_listen roscpp file which the coding is copied from the listener in the tutorial. And I modify the coding for using it to subscribe the my lidar's signal topic. The coding as below is what I modified and my spec of my ROS

include "ros/ros.h"

include "std_msgs/String.h"

void laser_msg_Callback(const std_msgs::String::ConstPtr& msg)
{
  ROS_INFO("I heard: [%s]", msg->data.c_str());
}                  

int main(int argc, char **argv)
{

  ros::init(argc, argv, "sick_listener"); 

  ros::NodeHandle n;

  ros::Subscriber sub = n.subscribe("scan", 811, laser_msg_Callback);

  ros::spin();

  return 0;

}

Spec: ubuntu 14.04LTS, Jade ROS, sick tim 561 lidar

And These are the message type of the "lidar's topic" and "talker's topic which is from the tutorial" comparison:

 1. terry@terry-All-Series:~$ rostopic type  /chatter std_msgs/String
 2. terry@terry-All-Series:~$ rostopic type  /scan sensor_msgs/LaserScan

When I run the code of sick_listen, it shows the error as below:

[ INFO] [1451458683.021191460]: Waiting 50 seconds for device to connect.
[ INFO] [1451458683.021602292]: Succesfully connected to 192.168.1.144:2111
[ERROR] [1451458683.224815412]: Client [/sick_listener] wants topic /scan to have datatype/md5sum [std_msgs/String/992ce8a1687cec8c8bd883ec73ca41d1], but our version has [sensor_msgs/LaserScan/90c7ef2dc6895d81024acba2ac42f369]. Dropping connection.

I am a niewbe in the ROS and not to familiar to the c code,so do I need to use the other header of the code for the lidar? I would be thankful if someone can give me some direction.

@Humpelstilzchen If I use arduino board to get the hall sensor and I also launch the lidar, and then connect to the rviz, when I move the wheels and because the effect of the hall sensor, the location of my in the rviz will move,too?

Hello ROS users,

I have a 2D Lidar laser scanner(Sick TiM-561) works on the ubuntu 14.04LTS with ROS jade PC, and I have a computer which is embedded program controller for the vehicle. Now I want to use Lidar to scan the environment and use ROS PC to build the map and then build a path to feed the embedded program controller to control the steering wheel for following the path.

So here I need to mapping and a path signal for the controller, and then the controller just follow the path to the goal place.

My case is when Lidar scans a parallel parking space and ROS PC build a map, then if I want to pull my car into that parking space, the ROS will build a path for the controller to track it.

I saw this link but this is for the specified robot of ROS, but the robot which I want to contnot a ROS robot. Could someone can give me some directions? Thanks in advanced.

@NEngelhard, I saw it and I think I need to change the title because I need to transport the map which is just 0 or 1 signal or x,y location of the object and then feed that to the Non-ROS computer which is the controller let a robot know can really know the environment. But thanks anyway really.

@Humpelstilzchen, such as this arduino board. Because I don't have the specific hall sensor for ROS but my case just need to input the signal of hall sensor and Gyro...etc., so I need a interface to input these sensor signals. Thanks.

Hello ROS users,

If I have a wheel encoder(Vehicle's hall sensor), and I want to input the signal to my ROS computer. But there is no information about it. Does anyone know that? Do I need to use the other board to receive that? I will be thankful if someone can give me some direction. Thanks in advanced.

Because the lidar transmits the distance data to my ROS computer. Can the map_saver collect all the data of lidar and convert into the X,Y coordinate if the map? Thank you.

Hello ROS users,

Is it possible to use gmapping to build the map and transport the map to the Non-ROS computer?

To specify my question: I have a sick TiM 561 lidar(2D lidar) and I can launch it from the ROS package in the ubuntu 14.04LTS ROS

computer. Because I need to build the map to let my vehicle knows where is it and then do some vehicle dynamic suck as

obstacle avoidance and parking. Therefore, I want to use the gmapping to build the maps and I want to transport the map

to the Non-ROS computer. But is it really possible to transport the map which is built by the gmapping to the Non-ROS

computer? Does someone know? Could you give me some directions or suggestions. Thanks in advanced.

@ahendrix, If I need to use UDP to transport the data of subscriber, do I just need to put the UDP code in the subscriber's roscpp? Sorry I'm not familiar about the C code and I'm a ROS newbie, hope you can help me about these questions. Thanks in advanced.