Java runs remote-controlled Mars rover

zdnet.con ^ | January 16, 2004, 6:20 AM PT | Reuters

[amigatec]

This explains why the first images of Mars wasn't the BSOD.

[amigatec]

This isn't a Linux post but you might what a PING anyway.

[skeeter]

Java has run me every day for the past twenty years.

[BenLurkin]

YUp. Same here for nigh on thirty years now:

[RandomUserName]

Very misleading title and article. Java runs the stuff on the ground on this end. A conventional RTOS (Real Time Operating System) from Wind River Systems runs on the rover itself.

[FastCoyote]

The article is related to Linux because GCC is bulding a compiler to run Java as native compiled code on unix boxes.

[jscd3]

This also explains why the rover took a couple of days before it could move one inch...

[newguy357]

This explains why the first images of Mars wasn't the BSOD

It also explains why it took days to get anything.

[newguy357]

You beat me

[FastCoyote]

Most of Java's slowness is in the load time, which doesn't matter for continual operation. But if you think Java is slow, see how long it takes to load a Microsoft .exe on a Unix box :)

[stripes1776]

Very misleading title and article.

What is misleading is calling Java an operating system. It's not an operating system. It's a programming language that compiles to byte code. It requires a Java "virtual machine" installed on an operating system to run.

Java runs the stuff on the ground on this end.

The engineers and scientists on the ground are using a program written in Java. But the article doesn't say what operating system they are using. They could be using a variety of operating systems. The Java program would run on all of them if there is a Java virtual machine installed on them.

A conventional RTOS (Real Time Operating System) from Wind River Systems runs on the rover itself.

That is corrrect. But there has to be some program running on the RTOS, probably written in the version of Java for embedded systems. From the tone of the article, I would guess that is the case, although there aren't many details given. I will poke around NASA's website and see if they give a better description of how they did things.

[gcruse]

According to the JPL they are actually using something very much like Maestro to run things.

[amigatec]

According to the JPL they are actually using something very much like Maestro to run things.

You can download Maestro from there website and install it. It works fairly well.

[theFIRMbss]

> But if you think Java is slow, see how long it takes to load a Microsoft .exe ...

Arf! That's like saying
you're not nuts because you are
saner than Manson...

[gcruse]

I've had Maestro for the last week. Sure wish they'd hurry up with the second data pack.

[dfwgator]

The article is related to Linux because GCC is bulding a compiler to run Java as native compiled code on unix boxes

About time someone thought about doing a Java compiler, wonder how it will compare with C/C++ compilers in performance?

[stripes1776]

According to the JPL they are actually using something very much like Maestro to run things.

Yes, Maestro is written in Java. It is clear that the scientists are using a Java program on their computers to communicate with and command the rover on Mars. What isn't clear is the language used to write the programs running on Rover itself. In the past these were written in C, C++, Lisp, or an assembly-like language. But on this mission, is the Rover itself running Java programs?

Here is a link to an article describing a talk given by James Gosling, the inventor of Java, at a Java conference last year. The following excerpt makes it clear that they will run Java on future rovers using a real-time version of Linux for embedded systems:

James Gosling, considered the father of the Java programming language and a Sun Fellow and VP at Sun Microsystems Laboratories, will deliver a keynote address and introduce the TimeSys-powered Mars rover at JavaOne on Wednesday, June 11, at the Moscone Center in San Francisco.

JPL and Sun are developing this vehicle as a proof of concept for the next-generation of unmanned Mars exploration rovers, scheduled for launch in 2009. JPL is demonstrating the use of Java-based applications executed on a real-time Linux platform as an alternative to C/C++ applications on a traditional commercial RTOS. TimeSys Linux/Real-Time and JTime, the industry’s first RTSJ-compliant Java virtual machine (JVM), are serving as the foundation for this new concept vehicle.

[dfwgator]

As memory gets cheaper and processing power improves, the need for C/C++ in embedded systems would seem to be less and less compared to an easier to read/code/maintain languages such as Java.

[amigatec]

The article is related to Linux because GCC is bulding a compiler to run Java as native compiled code on unix boxes.

It appears that Maestro is built with gcc 2.96 and not gcc 3.3.1.

I had to install libraries from 2.96 to get it to run on Mandrake 9,2

[RandomUserName]

I went digging to try to find what's really running on the rovers. I came up pretty much empty. The nearest thing I could find is a statement here: "Wind River's software comes with compilers for C++, Ada, Assembly and other languages that allowed the programmers to write the rover's specialized routines."

It seems likely to me that if java were running on the rover, it would be more prominently mentioned.

So, I still don't know for sure what is running on the rovers, but unless I hear a clear statement that Java is, I will continue to assume it is not.

In any case, the title of this article is still very misleading. The article talks about the earth-based software, yet the title clearly states that Java is running the rover. Chalk that up to reporters who know nothing about computers.