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RoboRealm and Lego RCX Usb
Jan from Netherlands  [4 posts]
9 years
Hello,

I have connected a wireless camera to an Eminent video grabber.
When I use the RR program, I have a nice 25 FPS rate.
When I activate the LEGO controls module, the frame rate drops to 0.3 FPS.
Is this normal, or am I doinfg something wrong.
I have added a screen dump

program.robo
Anonymous 9 years
Jan,

Yes, this is normal since the communication to the RCX is quite slow. The Lego NXT module is a little better. The reasoning for the slower frame rate is that if you cannot communicate any quicker with the robot it doesn't make much sense to process video images that could not change the robot direction regardless.

If you are wanting to continue to use the LEGO RCX we can make some quick updates to improve the speed by not transmitting all the comands every cycle. If you notice on the Lego NXT interface you can switch on and off certain sections ... we can add the same to the RCX interface too which would help to speed up the FPS. Let us know ...

STeven.
Jan from Netherlands  [4 posts] 9 years
Steven,

Actually, the only three variables I need are COG_X, COG_Y and COG_BOX_SIZE.
If you can make a modification speeding up the frame-rate by only transmitting these three, it would be great.

Thanks,
Jan


Anonymous 9 years
Jan,

Acually I think you misunderstood my last posting. Those variables are created in RoboRealm that is running on your PC. Getting those variables via the API is not what is slowing down the framerate.

Sending the motor commands, reading the battery level, etc. from the RCX is what is slowing things down. I assume you probably don't need all that information from the RCX. We will see what we can do to speed that communication up a little but it is unlikely to be significant.

We are talking about the Lego RCX and NOT the Lego NXT correct?

STeven.
Jan from Netherlands  [4 posts] 9 years
Steven,

You are correct, it is the RCX (usb).
To control the robot, I only need the X,Y and box size sent trough the IR tower to the RCX.
There is no need for any additional info sent or received to/from the RCX.

Thanks,
Jan
Anonymous 9 years
Jan,

We tried a couple of things with minor improvement. You can try by downloading the latest version and see if it makes any difference.

If you can just use the motor values without sending a variable to an RCX mailbox (the COG_BOX_SIZE) as this seems to be where the slowdown really occurs.

STeven.
Jan from Netherlands  [4 posts] 8 years
Steven,

I have tried different things, the fps stays less then 1. The robot is working but too slow responding.  I realize this is due to the lego module.  Is it possible to use a serial port connection? The lego tower is just a infrared port connected to the usb.  

I have tried to use some other programs.  It took me a lot of time with poor results.  I must say, your roborealm program has exactly the functionality I need, and with a click of the mouse available. Also the camera is inmidiatly recognised, it is easy to operate with the examples provided, a very usefull and userfriendly program.

Thanks,
Jan
bro  [5 posts] 8 years
i planning to buy a wireless camera and use a video audio grabber to connect to computer..can roborealm detect the camera and display the images..help me coz im new to this reborealm
Anonymous 8 years
ven,

Yes, please see the tutorial

http://www.roborealm.com/tutorial/ball_picker/slide010.php

where this was done.

STeven.

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