To LUGNET HomepageTo LUGNET News HomepageTo LUGNET Guide Homepage
 Help on Searching
 
Post new message to lugnet.robotics.handyboardOpen lugnet.robotics.handyboard in your NNTP NewsreaderTo LUGNET News Traffic PageSign In (Members)
 Robotics / Handy Board / 251
250  |  252
Subject: 
*WARM* L293D's on Handyboard
Newsgroups: 
lugnet.robotics.handyboard
Date: 
Mon, 1 Apr 1996 06:41:04 GMT
Original-From: 
shiller@localnet.com <stanley.hiller@localnet.comSPAMCAKE>
Viewed: 
1921 times
  
        Today I ran out to Toys 'R' Us and bought a wired-remote controlled
excavator to serve as the base for my HandyBoard. It seems to be causing me
a little problem, though. Before I removed it from the controller that
contained the battery compartment, it ran on 4 "C" cells.
        When I drive the motors from my HB, the L293D's get *very* hot (too
hot to touch) in a matter of seconds. From conversations with friends and
searching my mailing list archives, I've come up with two potential
solutions to this problem, and I'm hoping that someone can tell me which,
if either, will work; or suggest another way to go about keeping my motor
drivers from harm.
        From the mailing lists, it would seem that giving the HB a 6v
source instead of a 9.6v source to work with would solve the problem. Would
this do the trick?
        A friend of mine came up with the idea of using an op-amp to make
the motors draw power from another power source altogeather, with the motor
outputs serving as the signal inputs and a 6v 2.5Ah lead acid cell as the
power source (I ran the vehicle off of such a source with it's remote
control and it worked magnificently). This approach would seem to have the
added benefit of greatly extended battery life (for the HB itself and the
motors).
        So, would either of these schemes work? Are there other, more
simple/elegant solutions to this problem? Any information would be
appreciated, and, if there is any interest, I'll be happy to write up a
summary of any replies.


Thanks for your time,
Stan Hiller

P.S. For those of you who are curious, the excavator (about $40.00) is a
pretty neat critter (it's not unlike the other construction vehicles that
have been discussed on the lists of late). It's base is about a foot long
and eight inches wide, and it's got a pretty nice set of independantly
driven treads. It moves at a pretty good pace, too. It had a
semi-interesting scooping arm, but I've done away with that. I'm going to
flatten the base, glue some Lego plates onto it, and use the motor and gear
boxes from the arm's innards to make a more practical arm (that can grasp
things instead of just scooping them) out of Legos.



1 Message in This Thread:

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

Custom Search

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