RFID reader detector and tilt sensitive RFID tag
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Explore Community Submit RFID Reader Detector and Tilt-Sensitive RFID Tag by nmarquardt on October 30, 2008 Table of Contents intro: RFID Reader Detector and Tilt-Sensitive RFID Tag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 step 1: Material and Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 step 2: Building the RFID Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 step 3: RFID Reader Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 step 4: Tilt-Sensitive RFID Tag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 step 5: Variations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Related Instructables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Advertisements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Customized Instructable T-shirts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ intro: RFID Reader Detector and Tilt-Sensitive RFID Tag The 'rub' Want to detect the presence of RFID readers? Want to control when a RFID tag is active or readable? We describe how to do both using bits of copper and card, and some readily available electronics hardware. Longer preamble Radio frequency identification ( RFID) is rapidly growing in popularity. RFID tags are found everywhere. They're attached to container freight, in those funny-looking white labels you find in newly purchased books, embedded in many corporate ID cards and passports, etc. The tags have a few common properties: they transmit a unique ID number, are optimized to be 'read' from predefined distances, and are usually small so they can remain unobtrusive or hidden. RFID readers are used to track nearby tags by wirelessly reading a tag's unique ID (see Figure 4); a tag simply has to be brought into physical proximity with a reader to be read. Readers are mostly used for industrial or commercial purposes, e.g. asset tracking or electronic payment. Wal-mart use RFID tags and readers in their supply chain. The technology is also used in mass transit systems in cities like London and Hong Kong. In Japan, many mobile phones incorporate readers to enable e-money payments in shops and vending machines. For those of us who want to experiment with RFID, the problem is that the technology is almost always black boxed. That is, the inner workings of a tag and its interaction with a reader is hidden from view, and thus difficult to have much control over. In the two exercises that follow (building a RFID reader detector and a tilt-sensitive RFID tag), we offer an example of how you can start revealing some of the workings of RFID and thus gain some control over the technology. The two exercises also hopefully show that the technology is relatively simple and how it can be extended to support some interesting interactions. We offer some other possibilities that build on our examples at the end. Image Notes 1. Tilt-sensitive RFID tag Image Notes 1. Simple RFID reader detector Image Notes 1. Tilt-sensitive RFID tag 2. RFID reader detector Image Notes 1. Small RFID stickers 2. RFID tag in the form of a credit card 3. Inside of RFID tags: antenna and connected chip http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ step 1: Material and Tools This section provides an overview of the necessary materials and tools. Materials (see Figure 1): We need the following material to built the basic RFID reader detector. - Cardboard (around 100x70 mm) - Conductive copper tape (e.g., order number 1218478 at www.farnell.com) - Capacitor 82 pF (picofarad) (e.g., order number 1138852 at www.farnell.com) - Low current LED (light-emitting diode) (e.g., order number 1003207at www.farnell.com) Tools (see Figure 2 and 3): - Craft knife and scissors - Insulating tape (e.g., order number 1373979 at www.farnell.com) - Soldering iron and solder RFID reader for testing (see Figure 4): To test our RFID tags we need an RFID reader that can operate at a frequency of 13.56 MHz. There many readers for this widely used RFID standard, for instance the Sonmicro MIFARE USB reader (http://www.sonmicro.com/). Note: The Phidget RFID reader does not work with the tags created in this project, as it uses a different frequency for communication with the tags (125 kHz). Advanced material (see Figure 5): The following material is necessary to build the second part of the project: the tilt-sensitive RFID tag. - Micro tilt switches (e.g., www.digikey.com) - RFID ICs (e.g., MIFARE Standard 1k, part no. 568-2219-1-ND at www.digikey.com) Image Notes 1. Conductive copper tape 2. Capacitors (e.g., SMD) 82pF 3. Cardboard, around 100x70 mm 4. LED (light-emitting diode) Image Notes 1. Insulation tape Image Notes 1. Antenna of the Sonmicro RFID reader 2. Sonmicro 13.56 MHz RFID Module http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ Image Notes 1. Micro tilt switches 2. RFID ICs (MIFARE Standard 1k) step 2: Building the RFID Antenna This step describes how to build the antenna for the RFID tag. Building the RFID tag antenna To build the tag's antenna follow these three steps. 1. Cut the conductive copper tape into thin stripes of around 2mm (see Figure 1). 2. Tape these stripes (see Figure 2) in loops around one half of the cardboard (see Figure 3 for the layout of the antenna). The tag should have between 3-4 loops for the antenna. 3. Solder all the connections between the copper tape. Sometimes, this isn't necessary as the tape's adhesive backing is conductive, but solder the connections if you want to be on the safe side. Now we have created our RFID tag antenna, and we will add the "RFID reader detection" functionality in the following step. A little background RFID readers transmit an electromagnetic (EM) field with their reader antenna. This EM field induces a current in the antenna for all RFID tags within reading distance. This induced current activates the RFID chip that is connected to the tag's antenna. This chip then modulates a response (usually the unique ID number) that is transmitted back to the reader. The antenna of an RFID tag is usually a thin copper wire that is arranged in loops. The loops allow the emitted EM field of the RFID reader to induce current to the antenna of the tag. Image Notes 1. Thin stripes of the conductive copper tape (around 2 mm thick) Image Notes 1. Taping the copper stripes onto the cardboard http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ Image Notes 1. Three loops of the antenna Image Notes 1. Soldering the copper tape connections 2. Soldering the copper tape connections step 3: RFID Reader Detection This step describes how to add a simple mechanism to the RFID tag antenna that allows us detect nearby RFID readers. Antenna connection First, we add a small piece of insulation tape for the connection of the inner end of the antenna loop (as illustrated in Figure 1). This is to insulate the outer loops. Then we add another copper tape strip to the inner end of the antenna as shown in Figure 2. Here again we solder the two ends of the conductive copper tape together. Capacitor and LED Next, we add the capacitor (82 pF) and the low current LED to the tag as shown in Figure 3. They are connected in parallel. We also solder these two components to the copper tape (see Figure 4). Testing With these simple steps, our RFID reader detector is finished! By bringing our DIY RFID detector close to an RFID reader (as shown in Figure 5), the connected LED lights up. With the Sonmicro reader hardware the distance to the reader has to be below 8-10 cm; however, there are RFID readers available with a stronger EM field and therefore a higher maximum reading distance. In the next step of the instructable we will show how to extend a basic RFID tag and make it tilt-sensitive. Image Notes 1. Adding insulation tape for the connection Image Notes 1. Adding connection to the inner end of the antenna loops 2. Soldering connection again http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ Image Notes 1. 82pF Capacitor 2. Low current LED Image Notes 1. Soldering connections 2. Soldering connections Image Notes 1. RFID reader is near the tag 2. LED lights up step 4: Tilt-Sensitive RFID Tag We now describe the process of how to build a tilt-sensitive RFID tag. This extends the previous exercise. Antenna The antenna for this second RFID tag is similar to the first antenna we built. We thus need another piece of cardboard and to repeat the steps described earlier in STEP 2 of this instructable. Tilt-sensitive tag Next, we add additional copper tape connections to the tag, as shown in Figure 1. These connections allow us to connect three tilt switches, a capacitor, and the LED to the antenna. Again, all the connections of the copper tape are soldered together. We add the three tilt switches to the tag as shown in Figure 3. The tilt switches are soldered to the copper tape, and it is important to connect them in a slight angle (around 5-10 degrees) as shown in Figure 4. This makes sure that the silt switches are in a closed state while the RFID tag is in a horizontal position, and in a open state while the tag is in a vertical position. Again, we also add an LED and a capacitor to the antenna as shown in Figure 3 (we use a different form factor of the capacitor here just to illustrate the alternative options). Testing the tilt-sensitive tag We can now use our Sonmicro RFID reader again to test our new tilt-sensitive RFID tag. The tag is activate while in a horizontal position as in Figure 5, and is inactive when in a vertical position as in Figure 6. Using RFID chips We can now replace the connected capacitor and LED from our tag with an RFID chip (e.g., the MIFARE 1k shown in Figure 7). By doing this, the activity of our tag is no longer visible through the LED, but our tag is then readable by the RFID reader and responds with the unique ID number of the chip. http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ Image Notes 1. Additional copper tape for connecting the tilt switches, the capacitor, and the LED with the antenna. Image Notes 1. Again we use insulation tape for the connection 2. Soldering all copper tape connections Image Notes 1. SMD capacitor (82 pF) 2. Again a connected low current LED 3. This arrangement of the tilt sensors makes is possible to sense the horizontal or vertical position of the tag. Image Notes 1. The angle of the tilt sensors is important Image Notes 1. The tag is activated when it is in a horizontal position Image Notes 1. As long as the tag is in a vertical position, the tag is inactive http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ Image Notes 1. Using the MIFARE RFID chips to create a tilt-sensitive RFID tag step 5: Variations This section concludes our instructable of how to build custom RFID tags. Here are a few additional tags to show the possible variations. - Variable length of the tag antenna, and therefore also variable reading distance of the tag (Figure 1). - Experiments with the tag size and material (Figure 2) - Switching between the LED and an RFID chip (Figure 3) - Light-sensitive tag: the tag is active in daylight, and inactive in darkness (Figure 4) - Touch-sensitive: tag is active when someone touches the tag with a finger (Figure 5) - Different material for antenna by using conductive silver ink (Figure 6) - Stamped layout of an RFID tag antenna (Figure 7) that is in fact working! Many other variations of RFID tags are feasible Happy DIY! Image Notes 1. Variable length (and loops) of the antenna 2. Switch to activate and deactivate the RFID IC Image Notes 1. Experiments with form factors for the RFID tags http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ Image Notes 1. Button to switch between LED reader detection and the RFID tag 2. RFID chip MIFARE 1k Image Notes 1. Light sensitive tag Image Notes 1. Capacitive touch-sensitive pad 2. Voltage regulator 3. Diode Image Notes 1. Antenna layout painted with conductive silver ink. Image Notes 1. This antenna layout is stamped with conductive silver ink (and the antenna is in fact working!) http://www.instructables.com/id/RFID_Reader_Detector_and_Tilt_Sensitive_RFID_Tag/ Related Instructables RFID Proof Soda Can Wallet by prometheus442 How to block/kill RFID chips by w1n5t0n RFID Secure Wallet by dogsrcool2me How to make a RFID pet food access control system by mlarsen Accelerometer Tilt Controlled Wireless RGB LED-lights (video) by Andlier RFID Shielding Pouch Out of 'Trash' by laras Low Cost Water Flow Sensor and Ambient Display by staceyk How to make simple "motion" sensors by teebee918 Advertisements Customized Instructable T-shirts Comments 44 comments Add Comment i805 says: Nov 18, 2008. 11:02 AM REPLY i very much enjoyed this inscrutable and very educated too. would it possible to use a thin copper wire(0.1-0.5 mm) i pulled out of a small mooter ? from my understanding if i were to be near a shop with RF reader(those that prevent stealing)will it light? nmarquardt says: Nov 18, 2008. 11:57 AM REPLY Yes, this is absolutely possible. You can use thin copper wire for the antenna; in fact, most commercially available RFID tags use this material for their small integrated antennas. I've added a small image that shows such a tag and the thin wire of the antenna. However, if you create such an antenna by yourself, you have to do a few experiments with the length of the antenna wire as well as the number of loops. About your second question: you're right, a few of the security systems in stores use the 13.56 MHz RFID technology, so the LED of our simple detector would light up (I tested it :). However, quite many stores use different (sometimes proprietary) technology, that also uses a different frequency and protocols. In this case, the detector in its current form would not work, but you can modify the design (antenna, capacitor) to work with different RFID hardware and frequencies. zimmemic25 says: Nov 29, 2008. 1:54 AM REPLY there are some rfid stickers which have just 3 different shaped metal sheets laying on each other, how do they work? i805 says: Nov 22, 2008. 11:38 AM REPLY thanks if you say I'll have to try different lengths and loops than i give up cause i don't think it will be appropriate doing this near the RFID reader in the shop. another Q if the led will light will the RFID reader will beep too(in the shop)? [...]... filters and youll be able to look for multiple different kinds of RFID (i.e., different frequencies) http://www.instructables.com/id /RFID_ Reader_ Detector_ and_ Tilt_ Sensitive _RFID_ Tag/ Photo-Worx says: Nov 13, 2008 12:29 PM REPLY Another place to get an RFID reader and tags starter kit is at Parallax This kit only costs $45.99 and will work with a microcontroller or a pc Comes with a variety of tags too... readability of the RFID card There is a bit optimization of the antenna design necessary (antenna length and layout) to design them in a way that the two antennas don't influence each other But this is definitely possible to do; we tried this with another experiment of "twin-antennas" on a single RFID tag http://www.instructables.com/id /RFID_ Reader_ Detector_ and_ Tilt_ Sensitive _RFID_ Tag/ ... their service for other tags, and users that are interested in that should send them an email Besides that: your idea of working around a software filter on the firmware sounds also like an interesting hack :) http://www.instructables.com/id /RFID_ Reader_ Detector_ and_ Tilt_ Sensitive _RFID_ Tag/ Sparrowhawk says: Nov 11, 2008 4:27 PM REPLY It would be great to combine one of these detectors with a secure... of software (for the reader and of the tag IC) The mentioned Sonmicro reader provides a set of development tools, libraries, etc On the side of the RFID IC, we used Mifare 1k, 4k, and a few others While we did more experiments with reading and writing of these tags, we did not yet develop custom ICs for RFID necessary knowledge: so far I've built around 25 of various custom RFID tags, with different... great starting point for experiments with RFID The basic 'detection' of this reader with our detector- tag should would work right away (because they use the same frequency) If you want to build custom RFID tags for this, you could also think about trying to use one of their special tags, remove parts of the tag to find contacts to the chip, and then add the tilt switches or any other sensors to it Otherwise,... their provided software tools you can write data (around 600 bytes and more) to the tag However, if all the other RFID readers will then access this data is maybe not always the case, as they use proprietary protocols http://www.instructables.com/id /RFID_ Reader_ Detector_ and_ Tilt_ Sensitive _RFID_ Tag/ msweston says: Nov 11, 2008 12:25 PM REPLY This is really cool I like the idea of being able to paint electronics... pics, and useful as well as simple information Fav + 5/5 Cheers, Mspark400 benz_z says: Nov 11, 2008 2:57 PM REPLY nice -ible, can rfid tags be read trough fariday cages ? nmarquardt says: Nov 11, 2008 3:28 PM REPLY Faraday cages are in fact a very good 'shield' around RFID tags and prevents that tags inside of the Faraday cage are detected by the RFID reader This protection would be the same for the tags... REPLY RFID readers are usually quite (and unjustifiably!) expensive - The one mentioned in this instructible is nearly $150 for the USB version Take a look at http://tikitag.com They do a starter kit of tags and reader for about $50 It looks a bit proprietary, but it does work at 13.56MHz, and reading s/w is available for Windows, MacOS and Linux (Debian/Gnome only, as far as I can tell) The reader. .. pot' tag on the outside with a custom message like "Byte Me" or "Hands up, Sucka!" nmarquardt says: Nov 19, 2008 11:12 PM REPLY There are many RFID readers available that let you write data onto the tags; for instance the mentioned Sonmicro RFID reader (but many others are mentioned in the comments here) With their provided software tools you can write data (around 600 bytes and more) to the tag However,... No, these simple RFID detectors (via inductive coupling) are usually invisible for the RFID readers in shops Furthermore, the RFID readers for security in shops usually respond to a specific signature on the chips However, sometimes they are tuned very badly, which means they give a lot of false alarms, and then they might also give alarm when only this simple circuit is near the RFID reader In all cases . 10 http://www.instructables.com/id /RFID_ Reader_ Detector_ and_ Tilt_ Sensitive _RFID_ Tag/ intro: RFID Reader Detector and Tilt- Sensitive RFID Tag The 'rub' Want to detect the presence of RFID readers? Want to. Notes 1. Tilt- sensitive RFID tag Image Notes 1. Simple RFID reader detector Image Notes 1. Tilt- sensitive RFID tag 2. RFID reader detector Image Notes 1. Small RFID stickers 2. RFID tag in the. http://www.instructables.com/id /RFID_ Reader_ Detector_ and_ Tilt_ Sensitive _RFID_ Tag/ Home Sign Up! Explore Community Submit RFID Reader Detector and Tilt- Sensitive RFID Tag by nmarquardt on October