Newsgroups: comp.robotics
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From: nagle@netcom.com (John Nagle)
Subject: Re: Polariod sonar blanking dilemma 
Message-ID: <nagleCF4nvL.J1C@netcom.com>
Organization: NETCOM On-line Communication Services (408 241-9760 guest)
References: <1993Oct18.214610.20660@ncsu.edu>
Date: Tue, 19 Oct 1993 04:45:20 GMT
Lines: 15

rmlegran@eos.ncsu.edu (RICHARD MARK LEGRAND) writes:
>I am using the infamous Polaroid sonar modules on an autonomous vehicle,
>and I am having problems with sensing obstacles less than a foot or
>so away from the transducer.

      It's a fundamental problem of a one-transducer system.  

      The real solution is to use separate transducers for send and
receive.  A number of mobile robot vendors have done this.  You'd have to
design new drive electronics, of course.  But it should't be that big a
deal.  You could probably still use the TI chipset.  (TL851/TL852)
This would be a nice little design project for somebody.

					John Nagle

