A step in the Right Direction....

So I'm back and working on the Java environment. I have been able to get the firmware to download to the RCX unit once again. I ended up googling "leJOS 3 serial port", which ended up leading me to a page that gave me information that the error I was getting was related to bad code in the 3 release. I followed the directions/suggestions that was suggested for getting the firmware to download. The summary of the fix was to copy files for the COM port from version 2 and replace the version 3 files. So right now I am sitting with an RCX brick that is ready to receive the Compiled Java code, which I would love to get to download. But I have received a large error message about not being able to find certain file(s), so hopefully I will be able to find a solution pretty quickly on the leJOS forum.

(I once again edited out the user name to protect the identity of the computer.)

On another note: To account for the time of when Uni was closed on Friday...what did I do you ask. Well honestly I didn't do anything but I made up for it on Saturday by working 3 hours on my paper. The good news is that it is pretty close to done, of course if I get the Java up and running I will have some revisions to make.

Time worked Since Last Post: 4 hours 15 minutes
Overall: 37 hours 40 minutes

More on Trouble Shooting...Back Tracking....

As I have been informed, dealing with hardware related issues can make life tough and difficult. Through out my independent study, I have dealt with the problem of getting programs to transmit from the computer to the RCX unit. And just when I thought that I had figured it out (problem being that it didn't want to transmit when I was remoted into the computer), I find that once again, I am trying to figure why it won't transmit.

Since the last post I have:

• Changed the battery in the IR transmitter (Doesn't seem to make a difference, although plugging it in fully does)
• Tried changing a setting on the Serial Port through Windows, since someone mentioned on a forum that they had been able to get it to work but that it ran slow...so I tried turning off a buffer setting to see if that made a difference. It didn't. I then turned it back on.
• So I then decided to see if I could load the Lego firmware back onto the RCX, it did it. Just fine and dandy!! I was able to load a NQC program on to the RCX brick and it worked just fine.

What I am thinking could be the problem is that the leJOS for the RCX is no longer being supported and Java has since moved onto a newer version. According to the leJOS website, it should work with Java 1.1 -1.5, I think that we might be on Java 1.6 or version 6 (that is if they haven't changed their confusing ways ;-) )So my next plan of action is to go dig up an older installer of Java that I have, in hopes that maybe installing an older Java will fix the problem and that any problems I do face, I will be able to solve quickly since I might have already seen them.

On a happier note: In doing this trouble shooting, I reinstalled the NQC program for my LucyLeia (she was still all together....Just wasn't connected to her brain ;-)). Then after reconnecting her up and running the program, I noticed she switch which side of her that she was putting the colors on. Taking a wild guess that this might have to do with the orientation of the Lego block with the wire was plugged onto the RCX, I turned it by 90 degrees so that the wire was now running off the side instead of the bottom, like I had first reconnected it. Ran the program again. And Exciting stuff....she switched back to the sides that she was dropping them before, when I first had connected her up.

Time since last post: 2 hours
Overall: 33 hours 25 minutes

Still Trouble Shooting....

To continue on from where I was yesterday....With the lovely error of not being able to find the classes....This is where I started today....I have since tried multiple things to try and solve that error, which it seems that I may have. I know receive an error of not finding the Tower. Specifically: "error while downloading: Tower error: write failure". But let us back track and see what I did to get here.

• Multiple deleting of files and recopying: I have deleted the folder that I had put the leGOS files into. Copied over straight the newer 3 version with no version 2 files in the folder. Still getting the error. Deleted files again copied over version 2 files and then copied over only one file from version 3, in hopes that that would take care of both the former problem (that was corrected with version 3) and the new one. And then reverted back to only having version 3 files in the folder.
• Our friend Google, linked me out to a forum, where someone mentioned that to fix their problem they had to change the RCXTTY =USB variable to all lower case. So I tried that with my RCXTTY=COM variable...after making it lower case and putting a 1 directly behind it (and a couple of good old reboots), I got a new error....

"error while downloading: Tower error: bad ir link"....Have yet to google this one or try changing out the battery but from what I have read the IR tower is only suppose to be turned on when transmitting data or when the green light is on. So I have not yet pursued that route.

Time for today: 2 hours
Overall: 31 hours 25 minutes

Working with leGOS

As I said in the last post, I started by getting the firmware downloaded to the RCX unit. That was successful. I then continued on in the tutorial by typing out the testing code (in Notepad ++ of course). The typing out went fine ;-).....Things are looking grand....then comes the "head banging error" you know the type....."Why are you giving me that? I "thought" I followed everything to a T"....Very well time for....Google....What errors did I get you ask? Well lets see.....

• Can't find the lejosjc.bat Problem: setting the variable properly
  
• Can't find javac (being called by the lejosjc.bat) Problem: once again setting a variable properly (Can you tell that I typically don't have to do that all that often?)
  
• javac: target release 1.1 conflicts with default source release 1.5 Took the error code and used our good friend Google....came upon a website that suggested using leGOS 3 (which according to the website is a release candidate...), I unzipped the downloaded zip file and copied the new files over to the original legos folder. (Note: I did not delete out everything from that folder but just told it to replace what had the same name with the new data)

(I do realize that it is somewhat hard to read the lovely command line picture....but I thought that I would go ahead and add it. I also realize that the user name is blacked out...that is to protect the identity of the computer ;-))

I then reset paths and this allowed me to "compile" the program. I did run into a small error, but that was a typing error on my part. After finding said error, fixing it and saving the file. It compiled for me quite well.

Now comes the part when we download it to the RCX unit, Right? Of course not....now comes the time where we go back to trouble shooting because we get more errors....
What error(s) are we getting you ask?
"error while linking: No classes specified"
Google here we come....
To solve this lovely little error, I have tried putting in the CLASSPATH (again) and googling it. I have yet to find the fix on Google. And that is where I am now...thinking that I would possibly get to stop with success and yet getting to puzzle it over....

The JOYS of Programming :-D

Time since last post: 1 hour 45 minutes
Overall: 29 hours 25 minutes

Caleb Tricycle...Different Code...Same purpose....Needs adjustment

So only showing the successful programming code, would be unfair to people...since that is not really real world. I have now have downloaded a piece of code into Caleb Tricycle that does not work...Here are the results.....



I believe that the reason for this problem has to do with the numbers that are used by the robot coming from the light sensor are not set right. Basically, I need to go back and work with Caleb Tricycle to try and achieve numbers that allow him to turn according to what the light sensor says.

Why is this being posted after the successful post about Caleb Tricycle? Because I read in the Baum book about a different algorithm to use for a line follower and decided to try it with my modified Knudsen design. So right now...He just likes to run straight a head.

A quick note about the downloading problem....I am wondering if I am having the problem because the computer is some how getting confused, when I am switching back and forth from remote desktop to directly on the desktop. Just a guess....the last two times I downloaded a program, I was able to download it without restarting the Computer.

Back to program to try and figure out the numbers.

Hours worked since last post: 1 hour 10 minutes
Total for today: 3 hours 10 minutes
Overall: 17 hours 20 minutes

Tricycle...Continued

After reading Baum's book on the design of his line follower, I decided to modify the design of the robot to help keep as much outside light from the sensor as possible this is what I came up with....


I lowered the Light sensor by using a flat Lego piece, I then surround the light sensor with other Legos making sure that they didn't have holes that would allow light in. If they did, I used another flat Lego to cover up the hole. The picture on the far left shows what I ended up using to block out the light, I had run out of the wrap around Lego pieces that I used in the right picture, because I had used one to let the light sensor point down. The picture in the middle is what it looked like before.

I followed the program that was set out in Knudsen's book. The numbers in this picture are not the numbers I ended up using with the program, I started out with the numbers that are given in the book. Then adjusted them as I saw when using a guided mode in the Programming environment.


I once again ran into a problem of getting the program to download to the RCX, this time I decided to restart the computer and make sure that the RCX was on near the beginning of bringing up the program on the machine. It then transferred just fine and allowed me to use a mode to test the code to find out numbers that I needed to be able to tell when the sensor was picking up dark verse light. I was also able download the program a couple of times in order make adjustments to the numbers.

After watching the program run on the Robot, I had the thought that his back wheel reminded me of a dog's tail. I decided then that I should adjust his name to Caleb Tricycle...since Caleb means dog. So here is Caleb Tricycle running...including running off of the mat with the black trail that it is following. The mat came with the Lego Set.

Hours worked today: 2 hours
Hours overall: 16 hours 10 minutes

Trouble Shooting......With more that should be coming later today....

So I worked for about 30 minutes this morning on trying to figure out what is going on, why I can't get the program to transfer to the RCX. To show some other readers out there, who are not familiar with the set up....


The yellow brick is the RCX unit shown in another the post. The black unit standing up, is the IR transimitter, which is hooked up to the computer. The connection that it uses is a 9-pin serial connection (My guess what be that new models of the Lego Robots are now coming with USB connection....to answer a question of how it connects to the computer....according to the help that is linked in the next paragraph).

In the sense of trying to figure out why stuff won't transfer, I have tried googling the error message and got what I felt was very little help.... Try inserting new batteries into the RCX unit.....So Right now...This is what my "built" robot looks like.....


Two large pieces....because the battery section is on the bottom of the RCX, which makes sense for the buttons need to go on top....but it is a pain to change batteries then once the robot is built.

When that didn't work yesterday, I took books home with me to see if I could figure anything out. While since the message that I was getting was about the IR transmitter, I thought that maybe it some how drained its battery and needed a new one. So that is where I started this morning: Changing the 9 volt battery. I also checked the computer to make sure that the Device Manger was showing the port working (it was) and then told it to check for a new driver update (nothing was out there that was better....according to Windows)

The good news is that I got the IR transmitter to transfer the firmware to the RCX (it had "disappeared" since the batteries must have been out of the RCX unit for longer than a minute). Evidence:

The green light that is showing is blinks and lights up when the IR transmitter is transmitting data.

The numbers keep adding one while the firmware is transferring.

And that is all the farther I have gotten so far, as I had to run and go do something for a couple of hours....I am now back and am going to try to convince the software on the computer, the IR transmitter and the RCX unit to all work together and transfer the program!

Time Worked So far today: 1 hour
Time worked over all: 10 hours 30 minutes