原创 Tracking your engineering tools

Last week, I received an email from a reader who we shall call Larry (because that is his name). Larry's message was as follows:

Hi Max, I have been tasked to come up with a "workable" means of tracking our electrical engineering tools like scopes, meters, power supplies, J-LINKs, CAN bus converters, evaluation boards, compiler source, and the like. Currently, if we need an item, we first look in the engineering lab. If not found we then ask those most likely to have used it if they know where the item is. The next step is to send an email to everyone and hours or a day later you get a response. This is not a time-efficient system.

I thought that placing a RFID tag on each item and then use several RFID readers to triangulate the location of the item would be great. Turns out RFID readers with a range of 10 meters appear to be very expensive (>$1000).

A simple sign out or logging system has not worked very well. If someone finds the item sitting unused on a desk they use it without signing it out (probably intending to bring it right back).

I am sure this is not a new problem. Perhaps you or one of your readers has a workable solution.

Well, you can imagine me sitting up straight in my chair and sticking my chest out proudly, because in fact I have a brilliant solution...

In past columns, I've mentioned a company here in town (Huntsville, Alabama) called Synapse Wireless (www.Synapse-Wireless.com). These folks make mega-small (about 1.5" square), ultra-low-power wireless modules. When you power these little rascals up (the wireless modules, not the guys and gals at Synapse Wireless), they automatically form a full-up, low-power, wireless mesh network.

They have their own wireless stack called SNAP which has a really low memory footprint (~40KB). This means you can use the cheaper 8-bit, 16-bit, or 32-bit microcontrollers. The truly great thing is that you create your applications in the easy-to-learn and easy-to-use Python Scripting Language, and you download these applications "Over the Air" ... it's so easy even I can do it.

But wait, there's more. Larry mentioned that RFID readers with a range of 10 meters are really expensive. That's true. But short-range RFID readers that can mount on the side of a door and only have to cover things going through that door are much, MUCH cheaper.

The reason I'm so excited about all of this is that I remember chatting to the folks at Synapse some time ago, and they were telling me that one of their customers had implemented something almost exactly the same as the solution Larry is looking for.

Imagine this... every piece of electronic equipment has its own RFID tag. Every door in the facility has a low-cost RFID reader tied into a low-cost Synapse wireless module. Whenever a piece of equipment is moved in or out of a room, the RFID reader detects what equipment it is, and the Synapse wireless module transmits this information over the mesh.

One of the Synapse nodes is connected into a PC, which immediately uploads the data into a web-based database application. Now, if anyone in the company wants to locate "The 10GHz Oscilloscope" (or whatever name you associated with that RFID tag), they can just pull up a browser and access the database and see that five minutes ago it was carried into Room #123.

You could even go one farther than this. You could attach an RFID tag to each employee's badge, which means you now know who is carrying the equipment as it goes through a door. So now, when Larry wants the 10GHz Oscilloscope, rather than searching the building and uttering expletives and generally making a pain of himself, he could simply look at the online database and see that in fact he was the last one to touch this piece of equipment and he brought it into his own office a week last Thursday ... sort of thing.

OK, my job here is done. Anyone who is interested in learning more about this solution (or anything else you want to do with the Synapse Wireless Modules) can contact Bryan Floyd as follows (make sure you say "Max says Hi"):

Web: www.Synapse-Wireless.com
Email: Bryan.Floyd@Synapse-Wireless.com