I just joined MRL and have zero experience with JAVA. Host systems are CENTOS 6.5 Linux with JRE installed via Centos repositories. I am unable to successfully execute as eith user or root.

    java -jar myrobotlab.jar

Error message varies (no idea why) between unable to create java virtual machine and a spew of error messages indicating that it cannot process the file.

Google has reports that there may not be enough memory allocated and the syntax to increase it.

I wonder if it is related to CENTOS using OpenJava vs OracleJava.

Would appreciate feedback/hints/suggestions.



8 years 3 months ago

Hello and Welcome ggallant !

If it dies quickly there shouldn't be that much std output .. could you copy & paste it in an additional comment.  Also the bootstrap usually lasts long enough to generate a prelog.log - could you attach this file if it exists and maybe we'll get a better idea what is going wrong.



8 years 2 months ago

Did system update which include a new Java and switched from DeskTop to Laptop. Now getting a myrobotlab welcome screen. Will retry on desktop in two weeks. Info while running:

[mrl]$ java -jar myrobotlab.jar
starting bootstrap
333 INFO

Bootstrap starting spawn 20140905212925

333 INFO ============== args begin ==============

471 INFO jvmArgs []

471 INFO in []

471 INFO ============== args end ==============

473 INFO protected domain /home/ggallant/mrl/myrobotlab.jar

542 INFO platform x86.64.linux

599 INFO total physical memory returned is 7759 Mb

630 INFO spawning -> [/usr/lib/jvm/java-1.7.0-openjdk- -Djava.library.path=libraries/native/x86.64.linux -cp ./:./myrobotlab.jar:./libraries/jar/* org.myrobotlab.service.Runtime -service gui GUIService ]

653 INFO extracting ./libraries/jar

941 INFO Bootstrap finished spawn 20140905212925

leaving bootstrap


8 years 2 months ago

In reply to by ggallant

Great .. this gets us started...

java is 1.7 - check 

Platform is Linux (knew that from your Centos) - 64 bit Yay !

Questions :

  • Your starting this from a shell command on the desktop ?   This is not a ssh session is it ?
  • Can you try the spawn command ->  

    /usr/lib/jvm/java-1.7.0-openjdk- -Djava.library.path=libraries/native/x86.64.linux -cp ./:./myrobotlab.jar:./libraries/jar/* org.myrobotlab.service.Runtime -service gui GUIService

    and see what happens?  Is there a myrobotlab.log or just a prelog - if you get a myrobotlab.log - we have made it further - next will be to send me that one.


8 years 2 months ago

GroG, I think it is working. Attached is the log file. I cut & pasted your shouts last night to Nateo about getting started with an Arduino. Did not have an Arduino at hand but will try today. The only thing that did not work as directed was "runtime-> install all". I am currently working on two robots, a hexapod and a self balancer. Both have worked in the past but got major updates that have been slow to complete. Both contain NRF24L01 radios. The hexapod is controlled by an FPGA while the balancer is a dsPIC33. Neither compute engines appear to be in the current hardware list. From looking at the Arduino code it looks like I would need to write code to communicate via the radio and implement a robot based service that responds to commands. I find getting started with a new environment most challenging. Just getting comfortable with the work flow and jargon seems to take me longer than most people. Being a believer in the 90/10 rule I expect that mrl will do 90% of the work in the first 10% of time and then I will spend the remaining 90% doing the last 10% of the task.

Would really like to see your projects !  (If you feel inclined there is a Create Content link on the page - choose Blog - then this page explains how to add pictures & video - http://myrobotlab.org/content/helpful-myrobotlab-tips-and-tricks-0

Gareth here uses a FPGA (albiet he's using it with a Parallax Prop emulator) - 
If its getting raw serial information to/from some board MRL is capable of doing that just with the Serial service.

Ya, at the moment we are going through some flux - especially around Arduino .. but from the sounds of your hardware you might just need/want the Serial service.



I got to MRL via Gareth's post on Lets Make Robots. He has a lot of progress expressed in a few words!!! I have similar hardware here but only 17 open projects to complete before starting on another.

My current top priority project is a lake water temperature sensor. It will have multiple temperature sensors and an ambient light sensor. The temperature sensors are at 1 meter depth increments. Want to do a 6 months monitoring (May thru Oct) depending on the ice conditions. Wondering if MRL would be suitable for displaying the results. I should be deploying a single temp sensor this week. Having difficulties with making water tight housing!!!! Prototype electronic unit is Arduino based, field unit will be PIC24 based.


Sure MRL could display, and save the data for you.. It can also relay it to ThingSpeak in the ThingSpeak Service - http://myrobotlab.org/service/ThingSpeak 

If you post details about any project we would certainly be able to support you more ..  as it is .. we are a bit blind without the details -  However, the Serial service is usually a good "jack-of-all-trades" Service to interface with any hardware