---- START NEW MESSAGE --- Received: from cherry.ease.lsoft.com [209.119.0.109] by dpmail10.doteasy.com with ESMTP (SMTPD32-8.05) id A7FAEF400D8; Fri, 30 Jan 2004 14:17:30 -0800 Received: from PEAR.EASE.LSOFT.COM (209.119.0.19) by cherry.ease.lsoft.com (LSMTP for Digital Unix v1.1b) with SMTP id <11.00CC5670@cherry.ease.lsoft.com>; Fri, 30 Jan 2004 17:17:13 -0500 Received: from MITVMA.MIT.EDU by MITVMA.MIT.EDU (LISTSERV-TCP/IP release 1.8e) with spool id 6948 for PICLIST@MITVMA.MIT.EDU; Fri, 30 Jan 2004 17:17:06 -0500 Received: from MITVMA (NJE origin SMTP@MITVMA) by MITVMA.MIT.EDU (LMail V1.2d/1.8d) with BSMTP id 2254; Fri, 30 Jan 2004 17:16:03 -0500 Received: from mxsf14.cluster1.charter.net [209.225.28.214] by mitvma.mit.edu (IBM VM SMTP Level 430) via TCP with ESMTP ; Fri, 30 Jan 2004 17:16:03 EST X-Comment: mitvma.mit.edu: Mail was sent by mxsf14.cluster1.charter.net Received: from charter.net (c68.112.190.250.fdl.wi.charter.com [68.112.190.250]) by mxsf14.cluster1.charter.net (8.12.10/8.12.8) with ESMTP id i0UM3lis082494 for ; Fri, 30 Jan 2004 17:03:49 -0500 (EST) (envelope-from rinelson@charter.net) User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax; CDonDemand-Dom) X-Accept-Language: en-us, en MIME-Version: 1.0 References: <401A9A93.20071.28A7C0C@localhost> <006201c3e75d$14b7f200$0301a8c0@user88l53zxzyb> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Message-ID: <401AD626.9070901@charter.net> Date: Fri, 30 Jan 2004 16:09:42 -0600 Reply-To: pic microcontroller discussion list Sender: pic microcontroller discussion list From: THE NELSONS Subject: Re: [EE]: Challenge for keen minds To: PICLIST@MITVMA.MIT.EDU In-Reply-To: <006201c3e75d$14b7f200$0301a8c0@user88l53zxzyb> Precedence: list X-RCPT-TO: Status: U X-UIDL: 371856591 Some things to consider. What is the value of the items being stolen and the punishment for stealing them? If the persons stealing the items finds the data logger and knows what it is and destroys it then it is useless. most criminals will destroy the things that can identify them. The data logger has to be kept secret and hidden to be of use. And in the court system here in the USA after first court case the secret is out. I think if the box is light tight use a light detecter and make the data logger as small as possible and keep it hidden and secret. Bob Pedro Drummond wrote: >Thank you all for the help and interest. > >Ok, time for more data: > >The space being protected is a metallic box, the size of an elevator, that >will be towed by small trucks. Its metallic "door" (actually a double door) >is the gate I mentioned. During long trips, these boxes are commonly moved >from truck to truck, with long periods waiting for the next one, with no >guards nearby. Although there is a very strong lock, theft was detected at >final destination in locked boxes (i.e., someone opened it, took some goods, >and somehow relocked it). A redesign of the metal box is being made, but it >will be a long time until all of them are replaced. It is enough for now to >help the insurance company in detecting WHEN and for HOW LONG it was opened, >so the responsible will be known. >I do not mind reading its information only when the gate is open, and I >cannot modify the gate, only add some small device close to the door. > > >To comment some of the group ideas: > >Using a contact method for data transfer - I am afraid of dust, grease, etc. >But maybe. >RFID - cheap tag, but expensive sensor (I guess). >Gyro/acceleration sensors - can't do, since it will be towed by a truck. >Hinge sensored - can't alter the hinge. > > >BTW, special thanks to Russel ! > >-- >http://www.piclist.com#nomail Going offline? Don't AutoReply us! >email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > > > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body .