Derkabub's profile - activity

Thanks for the reply. I have a topic on this posted to the sig/NXT and someone there indicated the same. I will look over the nxt-python bindings as you are indicating.

My set-up: -First edition Raspberry PI (Raspbian, running ROS Indigo) -Lego Mindstorms NXT I have catkin-ized ros-nxt -Connection with USB

Other devices connected via USB tested: -Toshiba Satellite laptop (running ROS Kinetic on Ubuntu 15.10) -gateway (M460E running ROS Indigo on Ubuntu 14.04 LTS)

The issue is that I can control the NXT via the teleop_keyboard app from the Toshiba and Gateway but I run into desired frequency issues on the Raspberry PI. It will work if I edit the .yaml file so the desired frequency is 2 hz for motors and 1 hz for the range sensor, but this does not work for control purposes. That and the left motor is out of sync with the right. No issues with motor syncing on the other two CPUs.

Thanks in advance!

I will provide more when / if I get more feedback.

I am seeing this also. My set-up is running ros-NXT over USB from a Raspberry PI. I have tried: Removing un-necessary USB devices from PI and then reducing all rates to 2 Hz. It respond to teleop_keyboard add but this is not adequate. Did you resolve this?

It seems I was simply making an error setting up my .yaml. In my .yaml that sets up the parameters I had "-type" but I was supposed to have "- type". Fixing this repaired the immediate issues. Thanks for your help!

As for your previous comment: If I use rospy.loginfo() to print 'config' to screen it prints the entire dictionary, which in my case only pertains to one sensor or a single dictonary. There are several sensors.

I am not sure how to report the source link being broken issue. There is more on this at sig/NXT. Between the ros wiki and the sig/NXT I figured out indiviuals working with this and selected a repository to grab the variant of ros nxt.

I am catkin-izing, updating, and making revisions to the nxt ROS packages. I have hit an issue that seems basic but I could use some help to get through it. Searches for accessing Python dictionaries haven't helped much.

The code:

host = rospy.get_param("~host", None)
sock = nxt.locator.find_one_brick(host)
b = sock.connect()

config = rospy.get_param("~"+ns)
components = []
for c in config:
    rospy.loginfo("Creating %s with name %s on %s",c['type'],c['name'],c['port'])
    if c['type'] == 'motor':
        components.append(Motor(c, b))
    elif c['type'] == 'touch':
        components.append(TouchSensor(c, b))
    elif c['type'] == 'ultrasonic':
        components.append(UltraSonicSensor(c, b))
    elif c['type'] == 'color':
        components.append(ColorSensor(c, b))
    elif c['type'] == 'intensity':
        components.append(IntensitySensor(c, b))
    elif c['type'] == 'gyro':
        components.append(GyroSensor(c, b))
    elif c['type'] == 'accelerometer':
        components.append(AccelerometerSensor(c, b))
    else:
        rospy.logerr('Invalid sensor/actuator type %s'%c['type'])

My issue is with the c['text'] in the for loop. When I print config[c] it prints the value of the key. Printing 'c' alone prints the key. However, when c['text'] is called ROS fires back an error:

TypeError: string indices must be intergers, not str

The namespace (returned into the config variable) can have several sensors set up by a .yaml file.

Thank you for your time.

I am told that there are some unofficial catkin-ized clones of the original repository on GitHub.

I got this from a comment from a comment at:

http://wiki.ros.org/sig/NXT

I will have to keep Jessie in mind. However, in the case of using ROS-NXT on the Raspberry PI (original PI not 2) needs at least the Mobile install.

Thanks for replying though, I am looking for ideas.

I am afraid that my raspberry PI is the original PI with the following specs:

700MHz Broadcom BCM2835 CPU / 512 MB SDRAM @ 400MHz

However, since I am more familiar with Ubuntu 14.04 LTS (Trusty Tahr) this is a great option.

Thanks I will keep this in mind.

I would rather use indigo. However, according to item 6 at the following link:

http://wiki.ros.org/nxt

rosbuild is required.

I am very new to both Linux and ROS so if there aren't explicit instructions I would not really be sure where to start. Any thought on accomplishing this?

From what I read from that post it seems to be for adapting the ROS-NXT to unbuntu 14.04.02. In my case I cant use Unbuntu on the raspberry pi. I do have ROS-Indigo working on unbuntu on my laptop.

For this project I need it to work on my raspberry pi and be able to run ROS Groovy for ROS-NXT.

I am trying to figure out the installation so i can connect a raspberry pi model A to connect to an NXT. The PI brick would be nice but I have an NXT brick and a raspberry pi on hand.

I do agree is that it would be a wonderful (and affordable) way to understand the workings of ROS.

I have a Lego Mindstorms NXT (the prior generation) I am afraid. I will keep this in mind for the future in case I have to go that way. Are you aware of any issues with connecting to the NXT?

My intention is to get Groovy running on Raspberry PI so I can work with ROS_NXT. I am trying to follow the guide:

http://wiki.ros.org/nxt

I run into issues while trying to install Groovy on raspberry pi using the following guide:

http://wiki.ros.org/groovy/Installati...

I get to item: 6. Build the Catkin Workspace

I attempt to run the following command:

Invoke catkin_make_isolated:

$ sudo ./src/catkin/bin/catkin_make_isolated --install --install-space /opt/ros/groovy

This results in the command not being found.

I then alter the command to run the python script named catkin_make_isolated which on my installation is located at:

/opt/ros/groovy/bin/catkin_make_isolated

This results in the error:

Traceback (most recent call last):
   File "/opt/ros/groovy/bin/catkin_make_isolated", line 11, in <module> from catkin.builder import build_workspace_isolated, colorize line, extract_cmake_and_make_arguments
ImportError: No module named catkin.builder

I have tried: 1. command: sudo apt-get --reinstall install python-catkin-pkg 2. running the commend to invoke catkin_make_isolated (minus sudo) after: sudo bash

I am obviously new to this and struggling to get past this error. Any help would be very welcome.

Thank you in advance.

I did go back and run the Talker Listener tutorial and that ran fine. The .py files are all in scripts in the recommended directory structure.

Sorry if this doesn't conform to convention but my response did not fit in the comment had to put in the answer field. Please read the next answer for my response.

Thanks!

The output of rospack:

Full tree crawl took 0.053591 seconds. Directories marked with (*) contain no manifest. You may

want to delete these directories. To get just of list of directories without manifests,

re-run the profile with --zombie-only

0.041185 /opt/ros/indigo/share

0.010218 /home/derkabub/catkin_ws

0.007243 * /home/derkabub/catkin_ws/devel

0.002643 * /home/derkabub/catkin_ws/devel/share

0.002243 * /home/derkabub/catkin_ws/devel/lib

0.002004 /home/derkabub/catkin_ws/src

0.001699 * /home/derkabub/catkin_ws/devel/lib/python2.7

0.001608 * /home/derkabub/catkin_ws/devel/share/common-lisp

0.001405 * /home/derkabub/catkin_ws/devel/lib/python2.7/dist-packages

0.001353 * /home/derkabub/catkin_ws/devel/share/common-lisp/ros

0.001038 * /home/derkabub/catkin_ws/devel/share/common-lisp/ros/beginner_tutorials

0.000778 * /home/derkabub/catkin_ws/devel/lib/python2.7/dist-packages/beginner_tutorials

0.000751 * /home/derkabub/catkin_ws/devel/etc

0.000569 * /home/derkabub/catkin_ws/devel/share/beginner_tutorials

0.000498 * /home/derkabub/catkin_ws/devel/include

0.000477 * /home/derkabub/catkin_ws/devel/etc/catkin

0.000184 * /home/derkabub/catkin_ws/devel/share/beginner_tutorials/cmake

0.000160 * /home/derkabub/catkin_ws/devel/share/common-lisp/ros/beginner_tutorials/srv

0.000139 * /home/derkabub/catkin_ws/devel/share/common-lisp/ros/beginner_tutorials/msg

0.000130 * /home/derkabub/catkin_ws/devel/include/beginner_tutorials

The package does show up in the rospack list-names.

I can see the package in the include directory but not the lib directory in devel under catkin_ws.

I just tried that with the following commends:

(after starting roscore and cd ~/catkin_ws)

catkin_make

source devel/setup.bash

rosrun beginner_tutorials add_two_ints_client.py

I still got ": No such file or directory"

Sorry so spelled out but I am fairly new to both Ubuntu and ROS. Thanks!

I attempted the tutorial at: http://wiki.ros.org/rospy_tutorials/T... as I thought the issue was something to do with this tutorial. This did not work. returned the error that there were no files specified in add_message_files in CMakeLists.txt. I would really appreciate help.

I have been running throught the Simple Service and Client tutorial (python) and everything seems fine until I run the rosrun beginner_tutorial add_two_ints(_client/_server).py command. I get ": No file or directory found" error.

I see the comment in the tutorial:

"We use CMake as our build system and, yes, you have to use it even for Python nodes." Assuming that the command that follow would take care of this I believe that this is done.

The files are in the advised directory and are executable (as there is a checkmark in the boxes indicating this in the file properties).

Is that somewhere else that I could check to ensure the rosrun can "see" these files?

PC OS: Unbuntu 14.04 ROS: Indigo