Re: H-bridge & Motor

[Tim Vanderhoek <vanderh@ecf.utoronto.ca>]

On Wed, Jan 19, 2000 at 02:10:53PM -0500, Joyce Poon wrote:
> 
> Bad News:
> The motor (esp the big one) draws so much current that all the transistors
> get VERY HOT.  The motors do not turn very fast either.  The little one is

More Bad News:  We're crossing emails.  :)

Or should I say we're "playing email tag"?  ;-)

The fact that the transistors get hot is not a problem.  The
transistors get hot when they are under constant use, but in the real
robot, they would only be under pulsed short-term use.  Without
testing real-world conditions, we can't say yet whether heat
production is a problem or not.

That fact that the motors to do turn very fast or with much torque,
is a problem.


> If we really have to stick with the big motors, another circuit (possibly
> the mixed relay-transistor circuit) to control the motors may be required.

This is Malone's reccomendation.  See earlier email.

> H-bridge good.
> Motor bad.
> Big motor makes Joyce >(

No Joyce, that's not true, and I think you should be a little more
mature.  A longer diatribe has been deleted.  If you want to discuss
this again, I'll happily discuss it with you again in person but not
in email.


-- 
Signature withheld by request of author.