Question about Lego Mindstorms Capabilities

[DeweyMec]

Hello, thank you for reading my question!

I am currently working on the creation of a teleoperated robotics lab. for a introductory robotics course. I wish to allow students to control a labyrinth-solver robot via Labview, with the Lego NXT toolbox. A computer server will be connected to the Lego via Bluetooth, and the student communicates with the server via  a web browser VI (a web published VI). I am interested on the Lego Mindstorm platform but I wanted to ask some questions about its software capabilities:

*Is it posible via a web VI interface for the student to load a program onto the Lego Mindstorm? My idea is to allow the student to load a VI (or the equivalent of a LEGO NXT ".exe")onto the server, and the server to load the program to the Lego. The Web VI already has some parameters the student can change a simple program execution (see [1]), but I also wanted to give the student the chance of loading their own program for more complicated algorithms.

Thank you in advanced for your time and patience!

[1] Maze Solving Algorithms

http://en.wikipedia.org/wiki/Maze_solving_algorithm

[ESearl]

Its possible to write VIs that will upload/download files from the NXT to your desktop as well as launch and abort the NXT executables. I don't know much about web-published vi, but it sounds like you will be able to do everything from your server vi.

[DeweyMec]

Thank you very much for your response

I was wondering, is it posible for Labview to compile the .RXE and save it as a file on the PC instead of automatically placing it in the Lego NXT? The students do not have their own NXT, so they cannot compile the .RXE to the lego and then uplad the .RXE to their PCs.

Thanks

[ESearl]

That functionality is not supported. After you compile and download you may upload the files back onto a PC through the NXT Terminal.

[patricia_ro]

hello i'm currently developping a  project to teleoperate a lego mindstorm by a joystick, using the nxt libraries in labview, i am trying to draw a path for areas that the lego mindstorm is going through in order to control the robot im trying to control the degrees goal so he can decide to go left, right or straight forward, everytime i try to incorporate to the vi the motors it shows me this errors:An error occurred during parsing. Node was unable to be parsed. I was wondering if any of you could tell me how to solve the problem thanks.

[patricia_ro]

thats the exact error, could it be something of the automathic update of the driver once the joystick was conected through the usb?

[ESearl]

Hi Patricia_ro,

I'm not familiar with this error. Could you attach the vi that produces the error?

[patricia_ro]

of course here it is part of it, the actual vi that shows the error is the one that closes the joystick, the main purpose is to control the movements by the axis info, just x,y in order to do so, but i haven't been able to make these decisions because right now the way it is, just shows those errors

[ESearl]

Hi,

What sort of joystick are you using? My guess is that it might not be supported by the inputDevice vis you are using. The error is probably happening earlier when you try and initialize the joystick but it is not reported until you close the joystick because you have wired the error terminals to the end. You might try using the "initialize keyboard" to see if that works any better.

Also, I noticed you used the orange motor vi to control the NXT Motors. The orange NXT vis are meant to be deployed as part of an autonomous program that runs without a connection to your computer. Since you are using the joystick vis which run on the computer, you will need to use the gray NXT vis. These are the ones intended to run on the computer.

(In labVIEW 8.5 the orange blocks will only work when you download your program to the NXT through the NXT Terminal, not when you press the run button.)

good luck.

[patricia_ro]

yes but, i think the joystick is suported by the vi because if i try it by it self without the nxt components it works perfectly, is an usb pc joystick maxfighter f-17, it doesn't need a driver i already checked, yes i usually run the program in the nxt with debug to see the results. I will try with the grey nxt too thanks