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I try use lcp_proxy for bind PC and Lego NXT. I got source:

svn co https://lejos.svn.sourceforge.net/svnroot/lejos lejos

I compiled lcp_proxy normal. I created file lcp_proxy.properties:

YAML-ROBOT-DESCRIPTOR: /home/alex/.ros/NXT2.yaml

I created file NXT2.yaml:

  - type: ultrasonic
    name: ultrasonic_sensor
    port: PORT_4
    spread_angle: 0.2
    min_range: 0.01
    max_range: 2.5
    desired_frequency: 10.0

I ran node lcp_proxy:

roslaunch lcp_proxy lcp_proxy.launch

and got error:

Loading node class: org.lejos.ros.nodes.LCPProxy
* Configurate ROS Node

* Running LCPProxy *

ROS Node Path: /home/alex/.ros/
* Reading property file
Path: /home/alex/.ros/lcp_proxy.properties
YAML: /home/alex/.ros/NXT2.yaml
* Connecting with a NXT brick
Exception in thread "pool-1-thread-7" java.lang.NoClassDefFoundError: lejos/nxt/remote/NXTCommRequest
    at org.lejos.ros.nodes.LCPProxy.connect(Unknown Source)
    at org.lejos.ros.nodes.LCPProxy.onStart(Unknown Source)
    at org.ros.internal.node.DefaultNode$1.run(DefaultNode.java:424)
    at org.ros.internal.node.DefaultNode$1.run(DefaultNode.java:421)
    at org.ros.concurrent.ListenerCollection$1.run(ListenerCollection.java:108)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
    at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.ClassNotFoundException: lejos.nxt.remote.NXTCommRequest
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
    ... 8 more
Mar 14, 2012 7:59:18 PM org.ros.internal.node.topic.DefaultPublisher$1 onMasterRegistrationSuccess
INFO: Publisher registered: Publisher<PublisherDefinition<PublisherIdentifier<NodeSlaveIdentifier</lcp_proxy,>, TopicIdentifier</rosout>>, TopicDefinition<TopicIdentifier</rosout>, MessageDefinition<rosgraph_msgs/Log, acffd30cd6b6de30f120938c17c593fb>>>>

Originally posted by Alexandr Buyval on ROS Answers with karma: 641 on 2012-03-14

Post score: 0


1 Answer 1


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nxt_lejos is at any early stage of development, and has not yet been used by anyone other than the developers.

Your problem is probably that pccomm.jar does not exist in the expected directory. You may need to edit the export section of manifest.xml and build.xml to change the paths to those used on your system, and then run rosmake. You will probably also need to build leJOS or install a Linux version of leJOS 0.9.1 on your system. To build from source, you can run the ant build.xml file in the snapshot directory.

There is a better replacement for lcp_proxy now - nxt_lejos_proxy, but that will probably have the same problems. There are installation instructions and a tutorial for nxt_lejos_proxy, but they have not yet been tested and will need improvement. nxt_lejos_proxy uses the parameter server and does not need the properties file.

Originally posted by LawrieGriffiths with karma: 131 on 2012-03-17

This answer was ACCEPTED on the original site

Post score: 1

Original comments

Comment by Alexandr Buyval on 2012-03-17:
Thank you! I have solved problem. I changed paths in manifest.xml

Comment by tfoote on 2012-03-18:
@Alexandr Buyval please accept this answer or make one of your own and accept it to show that it's been answered and others shouldn't try to help you.


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