To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.roboticsOpen lugnet.robotics in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / 7713
7712  |  7714
Subject: 
Re: controlling RCX from PC?!
Newsgroups: 
lugnet.robotics
Date: 
Wed, 27 Oct 1999 10:15:16 GMT
Viewed: 
521 times
  
nik heger wrote in message ...
all,
i have a little program that controls the RCX from the PC. i know
other people here have done that, so...

my major problem is that signal round trip time is very high - it
takes about 200 - 250 ms to send ONE command to the RCX (waiting for
the response included). this is WAY too long to do anything
interesting. in particular, i am trying to navigate the brick on a
set course of black stripes using the light sensors.
the only way i can currently get it to work is when i step the
motors, doing this:
- step (motors On and Off) ... 200ms
- test sensors ... 200 ms
- step.... and so on.

this makes the lego car crawl around the floor - not very impressive.


Remember the NASA Pathfinder? Signal round-trip was about 30 minutes! Still,
they did some interesting research. Try to put more decision-making
capabilities in the RCX itself and let the PC handle its behaviour on a more
global level.
What I'm trying to say is: Let the RCX do the driving and the PC do the
navigating. The 'driver' can decide when to stop for an obstacle. It can
also ask the navigator which way to go at an intersection. This way there
will be a lot less messaging going on, you can speed up your robot and still
avoid accidents. You will probably have to redesign your software to achieve
this.

Have fun,

Arjen



Message has 1 Reply:
  Re: controlling RCX from PC?!
 
(...) I agree with your conclusion (separating 'driving' from 'navigating'), but there is a slight difference between the RCX and Pathfinder: the latter had videocameras, allowing it to see much further and also understand better the environment. (...) (25 years ago, 27-Oct-99, to lugnet.robotics)

Message is in Reply To:
  controlling RCX from PC?!
 
all, i have a little program that controls the RCX from the PC. i know other people here have done that, so... my major problem is that signal round trip time is very high - it takes about 200 - 250 ms to send ONE command to the RCX (waiting for the (...) (25 years ago, 26-Oct-99, to lugnet.robotics)

4 Messages in This Thread:


Entire Thread on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact

This Message and its Replies on One Page:
Nested:  All | Brief | Compact | Dots
Linear:  All | Brief | Compact
    

Custom Search

©2005 LUGNET. All rights reserved. - hosted by steinbruch.info GbR