WEBVTT 1 00:00:00.080 --> 00:00:03.919 Imagine shedding your keys and passwords, entirely unlocking your car, 2 00:00:04.120 --> 00:00:07.160 your front door, even logging into your computer with just 3 00:00:07.200 --> 00:00:08.519 a simple wave of your hand. 4 00:00:08.640 --> 00:00:10.119 Sounds like science fiction, doesn't it? 5 00:00:10.119 --> 00:00:13.919 It really does. Well, Get ready because today we're embarking 6 00:00:14.000 --> 00:00:17.359 on a deep dive into the fascinating world of radio 7 00:00:17.399 --> 00:00:20.120 frequency identification or r FID. 8 00:00:20.399 --> 00:00:22.839 That's right, And for this deep dive, we're drawing our 9 00:00:22.879 --> 00:00:26.440 insights from a truly unique source. The book are FID 10 00:00:26.600 --> 00:00:31.160 Toys Cool Projects for Home, Office and Entertainment by Amal Grafstra. 11 00:00:31.440 --> 00:00:33.719 Yeah, it's a great one. Our mission today isn't just 12 00:00:33.759 --> 00:00:39.159 to explain RFID and dry technical terms. It's to cut 13 00:00:39.159 --> 00:00:42.359 through the jargon and show you how this star trek 14 00:00:42.600 --> 00:00:45.479 like tech which used to be mostly for big business, big. 15 00:00:45.320 --> 00:00:47.679 Warehouses, right supply chains and stuff. 16 00:00:47.359 --> 00:00:51.280 Exactly how it's surprisingly accessible now and applicable in your 17 00:00:51.359 --> 00:00:54.920 daily life. We're going to uncover some surprising ingenuity behind 18 00:00:54.960 --> 00:00:55.759 these projects, and. 19 00:00:55.759 --> 00:00:58.799 We'll also delve into the author's own remarkable personal journey. 20 00:00:59.280 --> 00:01:02.479 It all started with this, well, this real aha moment, 21 00:01:02.520 --> 00:01:02.799 fra him. 22 00:01:02.799 --> 00:01:04.680 Oh yeah, tell us about that. That's quite the story, 23 00:01:05.000 --> 00:01:05.599 it really is. 24 00:01:05.719 --> 00:01:10.719 Yeah, Amal Grafster's motivation came after he learned about contactless 25 00:01:10.840 --> 00:01:15.599 RFID technology being used for like pet identifications. 26 00:01:14.840 --> 00:01:17.079 Okay, little chips and casts and dogs. 27 00:01:16.840 --> 00:01:18.920 Exactly, And he thought, wait a minute, why couldn't I 28 00:01:19.000 --> 00:01:21.359 use that same tech for myself, you know, skip the 29 00:01:21.400 --> 00:01:23.239 access cards, build his own systems. 30 00:01:23.319 --> 00:01:25.359 And he actually got implants he did. 31 00:01:25.599 --> 00:01:30.599 To avoid carrying cards, that personal quest, that desire for 32 00:01:30.719 --> 00:01:34.319 ultimate convenience and control. That's what really ignited the passion 33 00:01:34.319 --> 00:01:35.400 that led to this whole book. 34 00:01:35.480 --> 00:01:38.719 Wow. Okay, so to really appreciate these these cool projects, 35 00:01:38.719 --> 00:01:41.840 we first need to understand the basics. What exactly is 36 00:01:42.000 --> 00:01:43.200 RFID at its core? 37 00:01:43.680 --> 00:01:46.000 Well, fundamentally, think of it as a two part system 38 00:01:46.159 --> 00:01:49.640 wireless communication. You've got interrogators, those are the readers, and 39 00:01:49.640 --> 00:01:51.640 then you have the tags, the little things you attached 40 00:01:51.640 --> 00:01:52.239 to objects. 41 00:01:52.280 --> 00:01:54.159 Okay, so it's a bit like a barcode scanner and 42 00:01:54.200 --> 00:01:55.480 a barcode label kind of. 43 00:01:55.560 --> 00:01:58.319 Yeah, that's a good analogy. But here's the key difference. 44 00:01:58.959 --> 00:02:02.840 R FID is completely contactless, which means you can identify 45 00:02:02.879 --> 00:02:05.719 objects even if they're hidden, you know, inside a box, 46 00:02:06.079 --> 00:02:08.840 moving down an assembly line, even wrapped in paper. No 47 00:02:08.960 --> 00:02:09.919 line of sight needed. 48 00:02:10.479 --> 00:02:14.840 Okay, that immediately sounds way more powerful than a traditional barcode. 49 00:02:14.879 --> 00:02:16.879 Oh it is, and it gets more specific too, right. 50 00:02:16.919 --> 00:02:19.599 Barcodes usually identify a type of thing, like all oranges 51 00:02:19.639 --> 00:02:21.319 have the same code exactly right. 52 00:02:21.439 --> 00:02:25.120 Our codes label the type like isku quanti three four 53 00:02:25.240 --> 00:02:30.039 means oranges. But RFID, well, it can assign each individual 54 00:02:30.080 --> 00:02:32.759 item its very own unique serial number. 55 00:02:32.919 --> 00:02:37.000 So not just the bin of oranges, but potentially each orange. 56 00:02:36.560 --> 00:02:39.919 Potentially yes, or each apple. Or think about a hospital 57 00:02:39.960 --> 00:02:42.800 tracking every single medical chart as it moves around. That's 58 00:02:42.840 --> 00:02:47.639 a huge leap in granular tracking, pinpoint inventory traceability. 59 00:02:48.120 --> 00:02:51.400 That is a powerful distinction. Now, when we talk RFID systems, 60 00:02:51.400 --> 00:02:55.159 you often hear active versus passive. What's the main difference there? 61 00:02:55.199 --> 00:02:55.879 Why does it matter? 62 00:02:55.960 --> 00:02:58.319 It's all about power how the tag gets its energy. 63 00:02:58.639 --> 00:03:02.479 Passive RFID tags have no internal power source, zero battery. 64 00:03:02.520 --> 00:03:03.719 Okay, so how do they work them? 65 00:03:03.759 --> 00:03:06.479 They actually draw their energy from the magnetic field the 66 00:03:06.520 --> 00:03:11.039 reader emits. The reader powers them up wirelessly just long 67 00:03:11.159 --> 00:03:12.159 enough for them to respond. 68 00:03:12.639 --> 00:03:14.840 Interesting, So what does that mean for performance? 69 00:03:15.080 --> 00:03:17.919 It means they generally have a shorter read range usually 70 00:03:18.159 --> 00:03:21.319 you know, inches up to maybe several feet. The big 71 00:03:21.360 --> 00:03:26.400 advantages though, they're cheaper, much lower cost per tag, and 72 00:03:26.439 --> 00:03:29.560 they have an essentially indefinite lifespan because there's no battery 73 00:03:29.599 --> 00:03:29.960 to die. 74 00:03:30.240 --> 00:03:31.960 Makes sense. The downsides the. 75 00:03:31.960 --> 00:03:34.800 Shorter range obviously, and they can be a bit sensitive 76 00:03:34.840 --> 00:03:38.280 to interference from things like metal and liquids, especially the 77 00:03:38.360 --> 00:03:39.400 higher frequency ones. 78 00:03:39.800 --> 00:03:42.759 Okay, so if passive tags are powered by the reader, 79 00:03:43.360 --> 00:03:47.800 then active RFID tags must carry their own power supply correct. 80 00:03:47.840 --> 00:03:49.919 Active tags have a little internal battery and. 81 00:03:49.879 --> 00:03:51.639 What does that unlock? What's the benefit? 82 00:03:51.800 --> 00:03:55.599 Range? Much much longer range, typically around say thirty feet 83 00:03:55.680 --> 00:03:56.879 sometimes even hundreds of feet. 84 00:03:56.919 --> 00:03:59.360 Wow, Okay, big difference, huge difference. 85 00:03:59.439 --> 00:04:02.400 The advantage is that impressive range and they can transmit 86 00:04:02.520 --> 00:04:05.479 constantly if needed. But the trade off is well, they 87 00:04:05.479 --> 00:04:06.919 cost more per tag. 88 00:04:06.680 --> 00:04:09.319 And the battery runs out eventually, exactly. 89 00:04:09.000 --> 00:04:12.080 Limited lifespan usually around three to five years, depending on 90 00:04:12.120 --> 00:04:14.879 the tag and how often it transmits. But it really 91 00:04:14.919 --> 00:04:18.480 extends the reach of RFID tracking dramatically. 92 00:04:18.639 --> 00:04:22.319 So beyond just identifying things, some tags are also read write. 93 00:04:22.439 --> 00:04:24.680 How does that expand what you can do? What's the 94 00:04:24.720 --> 00:04:25.360 insight there? 95 00:04:25.519 --> 00:04:28.040 Ah, this is where it gets really interesting. Read write 96 00:04:28.040 --> 00:04:32.600 tags mean you can store data directly on the tag itself. Okay, 97 00:04:32.680 --> 00:04:34.680 so the tag isn't just an ID number pointing to 98 00:04:34.720 --> 00:04:38.439 a database somewhere. It can actually carry relevant information with 99 00:04:38.600 --> 00:04:39.800 the item. 100 00:04:39.439 --> 00:04:40.480 Like what kind of information? 101 00:04:40.839 --> 00:04:44.279 Well, the book uses the example of say, white gym socks. 102 00:04:45.040 --> 00:04:47.519 Instead of the tag just spitting out an ID that 103 00:04:47.560 --> 00:04:50.000 your system then has to look up, the words white 104 00:04:50.040 --> 00:04:52.920 gym socks could literally be stored right on that tag. 105 00:04:53.120 --> 00:04:56.519 Huh. So the tag itself knows what it's attached to precisely. 106 00:04:56.920 --> 00:05:00.120 It makes the item sort of autonomous, carrying it its 107 00:05:00.120 --> 00:05:02.079 own data, and that can save a lot of money 108 00:05:02.120 --> 00:05:04.600 because you don't need network connectivity at every single scan 109 00:05:04.680 --> 00:05:06.720 point just to look up what an ID means. Right. 110 00:05:06.759 --> 00:05:09.720 It reduces the reliance on a central database exactly. 111 00:05:09.800 --> 00:05:13.759 It transforms a simple identifier into like a portable data packet. 112 00:05:14.000 --> 00:05:15.759 Really useful, very useful. 113 00:05:15.959 --> 00:05:19.240 But speaking of cost and ease of use, the book 114 00:05:19.360 --> 00:05:22.839 does mention a security aspect for some of these DIY projects, 115 00:05:23.000 --> 00:05:27.959 specifically using open format tags. What's the deal there, Yeah, that's. 116 00:05:27.839 --> 00:05:30.879 An important trade off to understand. These common tags like 117 00:05:31.160 --> 00:05:34.120 EM four one h two used in many projects. They 118 00:05:34.120 --> 00:05:37.240 can be read or even duplicated by anyone with the 119 00:05:37.319 --> 00:05:40.439 right equipment, and that equipment isn't very expensive. 120 00:05:40.120 --> 00:05:42.279 So not super secure then not in a high. 121 00:05:42.160 --> 00:05:45.519 Security sense, no, But the book kind of embraces this. 122 00:05:45.639 --> 00:05:50.600 It makes these projects cheap, easy and fun for hobbyists. Okay, 123 00:05:50.920 --> 00:05:53.399 and you know, for a home setup, it's often an 124 00:05:53.439 --> 00:05:56.720 acceptable compromise. As the author points out, the real world 125 00:05:56.759 --> 00:06:00.000 threat for your front door probably isn't someone sophisticated least 126 00:06:00.000 --> 00:06:01.480 boofing your RFID tag. 127 00:06:01.639 --> 00:06:04.079 Right, Someone's more likely to just break a window exactly. 128 00:06:04.120 --> 00:06:06.120 You have to consider the practical threat model. 129 00:06:06.160 --> 00:06:08.759 Okay, let's unpack that's further though, because a Mallgraf's just book. 130 00:06:09.000 --> 00:06:12.480 It isn't just theory, right, It's about making RFID personal 131 00:06:12.920 --> 00:06:16.160 using it in some surprisingly intimate ways. Absolutely, like the 132 00:06:16.319 --> 00:06:19.319 RFID enabled front door project. That sounds pretty cool. How 133 00:06:19.360 --> 00:06:20.240 does that actually work? 134 00:06:20.360 --> 00:06:22.600 It is cool. So for a home door, you're usually 135 00:06:22.600 --> 00:06:25.920 looking at using either an electronic strike what's that. It's 136 00:06:25.959 --> 00:06:28.720 a replacement for the strike plate in your doorframe. When 137 00:06:28.759 --> 00:06:32.480 it gets power, it essentially gives way and lets the 138 00:06:32.519 --> 00:06:35.399 door open even if the dead bolt latch is extended. Okay, 139 00:06:36.120 --> 00:06:40.079 or you modify a standard electronic dead bolt the book 140 00:06:40.120 --> 00:06:42.319 details how you can take something like a common keypad 141 00:06:42.399 --> 00:06:46.360 dead bolt and basically hack it rewire it to respond 142 00:06:46.480 --> 00:06:49.120 to an RFID reader instead of, or in addition to 143 00:06:49.160 --> 00:06:49.720 the keypad. 144 00:06:50.120 --> 00:06:53.519 So you're adapting existing hardware. How does the RFID part 145 00:06:53.560 --> 00:06:55.040 actually connect and control to lock? 146 00:06:55.079 --> 00:06:57.639 Then? Right, you build a little control box. The book 147 00:06:57.639 --> 00:07:00.399 shows how to integrate a simple say one hundred and 148 00:07:00.439 --> 00:07:03.759 twenty five Killer Herds RFID reader with a relay. A 149 00:07:03.839 --> 00:07:06.639 relay is just an electronic switch. It takes the signal 150 00:07:06.680 --> 00:07:09.160 from the reader and uses it to switch the power 151 00:07:09.199 --> 00:07:11.759 on or off to the electronic strike or the modified 152 00:07:11.759 --> 00:07:12.120 dead bolt. 153 00:07:12.240 --> 00:07:15.439 Gotcha, and there's usually an indicator light too, Yeah. 154 00:07:15.199 --> 00:07:18.160 Often an LED. The author shows how you can carefully 155 00:07:18.199 --> 00:07:20.800 modify the reader board like de Sodern and moving the 156 00:07:20.879 --> 00:07:23.759 USB connector to hide all the wiring inside the wall 157 00:07:23.839 --> 00:07:27.759 for really clean covert setup. The relay clicks the lock open, 158 00:07:27.839 --> 00:07:31.279 the LED might blink to show it worked. Visual feedback 159 00:07:31.319 --> 00:07:32.199 and what about the brains? 160 00:07:32.279 --> 00:07:34.000 Is there software involved? What does it do? 161 00:07:34.279 --> 00:07:38.720 Yes? Definitely. The author developed custom software called door FID. 162 00:07:39.399 --> 00:07:42.040 Its job is basically to listen for tag scans from 163 00:07:42.079 --> 00:07:44.519 the reader. Okay, then it checks the scan tag ID 164 00:07:44.639 --> 00:07:47.240 against a list of authorized IDs. If it's a match, 165 00:07:47.240 --> 00:07:49.560 it tells the relay to unlock the door, and it 166 00:07:49.600 --> 00:07:51.199 controls that led blink. 167 00:07:51.000 --> 00:07:53.399 And you can manage the tags, add new ones, remove 168 00:07:53.439 --> 00:07:54.639 old ones exactly. 169 00:07:55.079 --> 00:07:57.639 What's clever is it also lets you manage tags. Add 170 00:07:57.680 --> 00:08:00.319 your tag, your partner's tag, maybe a temporary tag for 171 00:08:00.360 --> 00:08:03.439 a guest. And you could even set time restrictions. 172 00:08:02.879 --> 00:08:05.360 Oh like for a cleaner or dog walker. 173 00:08:05.199 --> 00:08:09.279 Precisely their tag might only work, say Tuesday afternoons. 174 00:08:09.319 --> 00:08:09.800 That's neat. 175 00:08:09.920 --> 00:08:12.360 And again the book brings up that practical security point 176 00:08:12.600 --> 00:08:15.040 for a home door. Is someone really going to try 177 00:08:15.040 --> 00:08:19.360 and clone your tag from two inches away? Maybe, but 178 00:08:19.519 --> 00:08:22.879 breaking a window is probably faster and easier for most burglars. 179 00:08:23.120 --> 00:08:25.759 It forces you to think about the real vulnerabilities. 180 00:08:25.920 --> 00:08:28.759 That is a good dose of reality. Okay, so you've 181 00:08:28.800 --> 00:08:31.959 liberated your front door. The next logical step for many 182 00:08:31.959 --> 00:08:33.399 people their car. 183 00:08:33.840 --> 00:08:34.080 Right. 184 00:08:34.279 --> 00:08:38.440 How does RFID make keyless entry even more seamless, like 185 00:08:38.519 --> 00:08:39.759 no button presses at all? 186 00:08:40.200 --> 00:08:42.919 Yeah, the concept here is fantastic for convenience, especially when 187 00:08:42.919 --> 00:08:45.840 your hands are full. Imagine just bumping your hip where 188 00:08:45.879 --> 00:08:47.759 your keys are in your pocket against the spot. 189 00:08:47.519 --> 00:08:49.799 On the car and it unlocks, and it unlocks. 190 00:08:49.879 --> 00:08:53.600 The project uses a pretty simple, inexpensive access control kit. 191 00:08:54.080 --> 00:08:56.720 These kits can store say forty or fifty tags. They 192 00:08:56.799 --> 00:08:59.320 usually have a master tag for easy programming, and maybe 193 00:08:59.320 --> 00:09:00.919 give you an audible beep conformation. 194 00:09:01.159 --> 00:09:04.120 Antenna placement sounds like it would be critical here too. 195 00:09:04.279 --> 00:09:05.759 Where do you put it? Any challenges? 196 00:09:05.879 --> 00:09:09.039 Absolutely vital. The antenna coil is often quite delicate. You 197 00:09:09.080 --> 00:09:11.679 need to secure it carefully to a non metallic surface. 198 00:09:11.759 --> 00:09:13.240 Why non metality metal. 199 00:09:13.000 --> 00:09:15.480 Interfered badly with one hundred and twenty five kJ ever signal, 200 00:09:15.600 --> 00:09:18.200 Even though that frequency is generally more tolerant than higher ones, 201 00:09:18.279 --> 00:09:21.440 it just kills the range. So ideally you mount it 202 00:09:21.480 --> 00:09:24.360 near a window, maybe tucked under some plastic trim inside 203 00:09:24.360 --> 00:09:27.759 the car. Getting reliable reads without having to fumble around 204 00:09:28.159 --> 00:09:31.600 takes some careful placement. Every millimeter counts makes sense? 205 00:09:31.679 --> 00:09:34.480 And how does it actually talk to the car's locking system? 206 00:09:34.759 --> 00:09:36.919 A couple of ways. You can interface it with your 207 00:09:37.039 --> 00:09:41.320 existing keyless entry remote fob. Basically, you wire the RFID 208 00:09:41.480 --> 00:09:45.519 kits relay to simulate pressing the unlocked button on a 209 00:09:45.519 --> 00:09:48.360 spare fob you hide in the car, AH clever or 210 00:09:48.399 --> 00:09:51.080 you can wire more directly to the car's power lock actuators. 211 00:09:51.519 --> 00:09:53.879 The book tends to focus on simplicity here, so direct 212 00:09:53.919 --> 00:09:57.399 integration usually just handles unlocking, not locking, to keep the 213 00:09:57.440 --> 00:09:58.200 wiring easier. 214 00:09:58.279 --> 00:10:01.639 Gotcha, okay, front door car. What about your digital life? 215 00:10:02.039 --> 00:10:05.039 Logging into Windows XPI know a bit dated, but the 216 00:10:05.120 --> 00:10:08.159 concept with an RFID keyboard? How's that possible? 217 00:10:08.279 --> 00:10:11.240 This project is really neat. It involves physically modifying a 218 00:10:11.279 --> 00:10:14.799 standard USB keyboard like an old Microsoft Natural Elite. You 219 00:10:14.840 --> 00:10:18.399 basically open it up and integrate a small USB RFID 220 00:10:18.559 --> 00:10:22.919 reader and maybe a tiny USB hub inside the keyboard casing. 221 00:10:22.679 --> 00:10:23.759 So it all fits inside. 222 00:10:23.879 --> 00:10:27.240 Yeah. The goal is to have just one single standard 223 00:10:27.320 --> 00:10:29.519 USB cable coming out of the keyboard to your PC. 224 00:10:30.240 --> 00:10:35.159 It makes the RFID part completely invisible, totally seamless. 225 00:10:34.679 --> 00:10:36.559 With just typing, and when you wave your hand. 226 00:10:36.399 --> 00:10:38.840 It feels like magic. You just wave your authorized tag 227 00:10:38.879 --> 00:10:41.240 over a spot on the keyboard and boom, you're logged in. 228 00:10:41.559 --> 00:10:44.360 Okay, so the hardware is custom What about the software side? 229 00:10:44.399 --> 00:10:47.879 How do you make Windows accept an RFID tag instead 230 00:10:47.879 --> 00:10:48.600 of a password. 231 00:10:48.759 --> 00:10:50.960 That's where a clever bit of open source software comes 232 00:10:51.000 --> 00:10:54.120 in a tool called pgina, or specifically a module for 233 00:10:54.200 --> 00:10:58.679 it called Polgina dot dlll pgina. Yeah. It essentially acts 234 00:10:58.679 --> 00:11:01.360 as a replacement for this stand Windows login screen. The 235 00:11:01.399 --> 00:11:04.080 gena module pull Gina works as a kind of middleman. 236 00:11:04.480 --> 00:11:07.919 It intercepts the login process. It lets you link specific 237 00:11:08.080 --> 00:11:11.879 RFID tag IDs to your Windows username and password. When 238 00:11:11.919 --> 00:11:14.519 you scan your tag pule Gina looks up the associated 239 00:11:14.519 --> 00:11:17.639 credentials and automatically passes them to Windows, just as if 240 00:11:17.639 --> 00:11:18.879 you did type them in yourself. 241 00:11:19.159 --> 00:11:23.679 Wow. That sounds incredibly convenient, but also maybe a little 242 00:11:23.679 --> 00:11:25.240 concerning from a security standpoint. 243 00:11:25.240 --> 00:11:28.039 Does the book address that or absolutely it highlights a 244 00:11:28.080 --> 00:11:29.360 critical security aspect. 245 00:11:29.440 --> 00:11:29.639 Yeah. 246 00:11:29.720 --> 00:11:33.159 By default, the tag IDs and the link usernames and 247 00:11:33.200 --> 00:11:36.519 passwords are stored in plaintext right in the Windows. 248 00:11:36.279 --> 00:11:39.039 Registry plaintext, so anyone with admin access could just. 249 00:11:38.960 --> 00:11:42.240 Read them exactly. Anyone who can access the registry editor 250 00:11:42.240 --> 00:11:45.720 with admin rights could potentially see that mapping. The book 251 00:11:45.759 --> 00:11:49.360 suggests maybe trying to secure those specific registry keys as 252 00:11:49.360 --> 00:11:50.799 a possible mitigation. 253 00:11:50.519 --> 00:11:51.559 But is that fool proof? 254 00:11:51.639 --> 00:11:53.720 Well? It also notes that poule Gina itself runs with 255 00:11:53.759 --> 00:11:56.639 system privileges, which is the highest level on Windows, so 256 00:11:56.679 --> 00:11:59.240 it always has access regardless. It's really a classic example 257 00:11:59.279 --> 00:12:04.120 that trade off amazing convenience versus potential security exposure, especially 258 00:12:04.120 --> 00:12:06.399 on a shared or less secured machine. You have to 259 00:12:06.440 --> 00:12:09.759 weigh the risks for your situation. And what's fascinating here 260 00:12:10.240 --> 00:12:13.480 is how these components, these ideas from personal projects, they 261 00:12:13.480 --> 00:12:17.000 actually scale up. They can tackle more complex challenges, pushing 262 00:12:17.000 --> 00:12:19.440 what RFID can do beyond just the home. 263 00:12:19.600 --> 00:12:24.360 Think businesses, right, like the RFID enabled smart shelf. I 264 00:12:24.360 --> 00:12:28.200 can totally see that for business inventory tracking, medical supplies, 265 00:12:28.279 --> 00:12:30.120 maybe parts in a warehouse. 266 00:12:29.600 --> 00:12:33.480 Exactly common business applications, supply chains, tracking files. 267 00:12:33.759 --> 00:12:36.200 But how does that translate to home use. What's the 268 00:12:36.279 --> 00:12:38.399 insight for you and me? 269 00:12:38.919 --> 00:12:41.480 Well, the concept scales down perfectly. You could adapt it 270 00:12:41.519 --> 00:12:44.960 for your DVD collection, your books, maybe tools and garage. 271 00:12:45.120 --> 00:12:47.000 Okay, I see, so you always know what's on the 272 00:12:47.000 --> 00:12:48.360 shelf without having to look. 273 00:12:48.399 --> 00:12:52.440 Pretty much. The core idea is real time inventory without 274 00:12:52.440 --> 00:12:56.600 manual scanning. And a crucial feature for this, especially for 275 00:12:56.639 --> 00:12:59.559 shelves with lots of items, is something called anti collision. 276 00:12:59.639 --> 00:13:00.480 Anti collision. 277 00:13:00.600 --> 00:13:03.879 Yeah, the reader module used in the book's project, it's 278 00:13:03.919 --> 00:13:06.600 a thirteen point five to six Megohurst read write module 279 00:13:06.720 --> 00:13:09.480 supports it. It basically means the reader can talk to 280 00:13:09.559 --> 00:13:12.240 multiple tags on the shelf at the same time without 281 00:13:12.240 --> 00:13:14.679 them all trying to respond at once and just creating noise. 282 00:13:14.840 --> 00:13:16.679 Ah, so it can sort them out right. 283 00:13:16.720 --> 00:13:19.639 It interrogates them intelligently so they don't talk over each other. 284 00:13:19.960 --> 00:13:21.960 That means you can literally just glance at a screen 285 00:13:22.039 --> 00:13:24.480 connected to the shelf reader and get an instant list 286 00:13:24.480 --> 00:13:25.919 of everything that's currently sitting there. 287 00:13:25.960 --> 00:13:29.919 That's pretty powerful, so reading many tags at once. What 288 00:13:30.039 --> 00:13:33.120 are the practical challenges in setting up the antenna for 289 00:13:33.200 --> 00:13:34.600 something like that, like a whole shelf. 290 00:13:35.159 --> 00:13:38.360 Well, that thirteen point five to six Melhurst frequency. It's 291 00:13:38.639 --> 00:13:43.159 particularly sensitive to interference from metal and also liquids. Okay, 292 00:13:43.480 --> 00:13:46.159 so the pad antenna used in the project has to 293 00:13:46.240 --> 00:13:50.919 be mounted to a non metal shelf, wood, plastic, fine metal. 294 00:13:51.159 --> 00:13:54.240 Big problem, it'll absorb or reflect the signal badly. 295 00:13:54.600 --> 00:13:57.159 And getting good coverage over a whole shelf. 296 00:13:57.039 --> 00:13:59.759 That's the trick. It's a delicate balance. You might need 297 00:13:59.799 --> 00:14:02.919 moultiple readers and antennas for larger areas, or you'd have 298 00:14:02.960 --> 00:14:05.559 to invest in a much more powerful and therefore more 299 00:14:05.559 --> 00:14:09.799 expensive reader setup. Getting reliable reads across every spot on 300 00:14:09.840 --> 00:14:11.639 a full shelf. It's a bit of a tight rope 301 00:14:11.679 --> 00:14:12.480 walk right. 302 00:14:12.879 --> 00:14:15.759 Okay, So beyond organizing our stuff, the book also shows 303 00:14:15.759 --> 00:14:18.879 how our FID can help with our pets. The RFID 304 00:14:19.039 --> 00:14:20.639 pet door sounds like a fun one. 305 00:14:20.799 --> 00:14:23.120 Oh, it's a great project. And what's neat about this 306 00:14:23.159 --> 00:14:25.559 one is unlike some of the earlier projects that needed 307 00:14:25.600 --> 00:14:26.519 a PC connect it. 308 00:14:26.879 --> 00:14:29.480 Like the log and keyboard, right, the pet. 309 00:14:29.240 --> 00:14:32.759 Door is designed as a fully autonomous system. It uses 310 00:14:32.759 --> 00:14:36.480 an RFID module, but it's paired with a small microprocessor 311 00:14:36.559 --> 00:14:37.440 like a basic. 312 00:14:37.120 --> 00:14:39.480 Stamp, meaning it runs by itself exactly. 313 00:14:39.559 --> 00:14:43.120 It functions completely independently. It reads the tag on your 314 00:14:43.120 --> 00:14:46.440 pets caller and decides whether to unlock the flap, all 315 00:14:46.480 --> 00:14:50.039 without needing a computer nearby. Only opens for your pets tag. 316 00:14:50.159 --> 00:14:54.279 Okay, I can imagine antenna orientation being absolutely critical here 317 00:14:54.600 --> 00:14:57.399 the pets moving the tag on the caller might be 318 00:14:57.440 --> 00:14:58.279 flopping around. 319 00:14:58.679 --> 00:15:01.279 You've hit on a really key point. This project is 320 00:15:01.320 --> 00:15:05.519 a perfect illustration of a fundamental principle of passive RFID. 321 00:15:06.320 --> 00:15:07.600 It's not just about being. 322 00:15:07.440 --> 00:15:08.879 Close enough, it's about alignment. 323 00:15:09.080 --> 00:15:12.320 Yes, alignment is crucial for the tag to get enough 324 00:15:12.440 --> 00:15:15.000 energy from the reader's field. To power up and respond, 325 00:15:15.639 --> 00:15:18.320 the coil antenna inside the tag needs to be aligned 326 00:15:18.360 --> 00:15:21.519 more or less parallel with the reader's antenna coil. If 327 00:15:21.519 --> 00:15:24.919 it's perpendicular turn the wrong way, the magnetic coupling is 328 00:15:24.960 --> 00:15:26.480 really weak. It won't get enough power. 329 00:15:26.759 --> 00:15:29.200 Like trying to charge your phone wirelessly, the putting it 330 00:15:29.240 --> 00:15:30.000 on the charger. 331 00:15:29.759 --> 00:15:33.519 Sideways exactly like that. So the challenge is, how do 332 00:15:33.559 --> 00:15:35.720 you make sure the pets tag is facing the right 333 00:15:35.759 --> 00:15:37.279 way when they walk up to the door. 334 00:15:37.960 --> 00:15:39.840 Yeah, how do you solve that? You can't exactly train 335 00:15:39.879 --> 00:15:41.519 your cat to hold its head just right. 336 00:15:41.679 --> 00:15:46.279 Uh huh No. The book offers a really clever practical solution. 337 00:15:46.679 --> 00:15:52.360 It's suggest using those small, flexible wristband style RFID tags. Okay, 338 00:15:52.600 --> 00:15:54.000 got the band part off, So you just have the 339 00:15:54.039 --> 00:15:56.759 tag module. Then you actually sow that module into the 340 00:15:56.759 --> 00:16:00.399 pets collar. And here's the trick. You also so in 341 00:16:00.480 --> 00:16:03.080 something with a bit of weight like their metal name 342 00:16:03.120 --> 00:16:07.879 tag positions so it naturally pulls the RFID tag module downwards. 343 00:16:08.120 --> 00:16:12.120 Ah, So gravity helps keep the tag oriented correctly facing 344 00:16:12.200 --> 00:16:14.600 the reader antenna, which would be low down in the doorframe. 345 00:16:14.919 --> 00:16:17.559 Precisely. It leverages the weight of the name tag to 346 00:16:17.639 --> 00:16:20.480 ensure the tag is usually facing downwards for an optimal 347 00:16:20.559 --> 00:16:23.200 read as the pet approaches. It's a really neat example 348 00:16:23.240 --> 00:16:26.600 of the kind of practical, ingenious problem solving you find 349 00:16:26.600 --> 00:16:27.279 throughout the book. 350 00:16:27.440 --> 00:16:31.759 That is clever. Okay, moving beyond Homan pets. Now, RFID 351 00:16:31.919 --> 00:16:36.759 scales up dramatically for tracking things like employees or valuable assets, right, 352 00:16:37.080 --> 00:16:39.440 and for that you need longer range. So we're talking 353 00:16:39.559 --> 00:16:40.960 active RFID exactly. 354 00:16:41.000 --> 00:16:43.960 Active RFID is a whole different ballgame because the tags 355 00:16:44.159 --> 00:16:45.200 have their own battery, right. 356 00:16:45.240 --> 00:16:47.279 We covered that power equals. 357 00:16:46.960 --> 00:16:49.919 Range yep, they don't need to rely on harvesting energy 358 00:16:49.960 --> 00:16:54.399 from the reader. This breaks that close range limitation. Systems 359 00:16:54.440 --> 00:16:56.720 like the four hundred and thirty three Meggahertz ones discussed 360 00:16:56.759 --> 00:16:59.799 in the book can offer ranges of you know, tens 361 00:16:59.879 --> 00:17:03.279 or even hundreds of feet. True wide area tracking. 362 00:17:03.000 --> 00:17:05.920 Becomes possible, and the book highlights a specific reader for this, 363 00:17:06.079 --> 00:17:09.519 the Wavetrend LRS two one. What's special about that one? 364 00:17:09.519 --> 00:17:10.519 For larger scale. 365 00:17:10.279 --> 00:17:12.319 Stuff, it has a few key features for that kind 366 00:17:12.319 --> 00:17:15.960 of application. One is support for RS four eight five networking. 367 00:17:16.039 --> 00:17:19.839 What's that It's a robust industrial communication standard unless you 368 00:17:19.960 --> 00:17:22.319 chain multiple readers together, up to two hundred and fifty 369 00:17:22.319 --> 00:17:25.119 five of them on a single long cable run, all 370 00:17:25.160 --> 00:17:27.599 connecting back to one PC. So you could cover a 371 00:17:27.720 --> 00:17:30.920 huge warehouse or office building with relatively simple wiring. 372 00:17:30.960 --> 00:17:33.039 Okay, that makes sense for big areas anything else. 373 00:17:33.319 --> 00:17:35.880 It also has adjustable gain. Think of it like a 374 00:17:35.960 --> 00:17:38.720 volume control for the reader's sensitivity or reach. 375 00:17:39.079 --> 00:17:40.000 Why would you need that. 376 00:17:40.079 --> 00:17:43.000 To fine tune the coverage area of each reader. You 377 00:17:43.079 --> 00:17:46.039 might want to prevent readers in adjacent zones from accidentally 378 00:17:46.079 --> 00:17:50.200 picking up the same tags, causing confusion. Adjustable gain lets 379 00:17:50.240 --> 00:17:52.240 you create more defined read zones. 380 00:17:52.559 --> 00:17:56.319 Gotcha? Any downsides for hobbyists? Well? 381 00:17:56.480 --> 00:17:59.960 The one quirk is that Wavetrend's official software development Kit, 382 00:18:00.200 --> 00:18:03.200 the SDK you'd normally use to write custom software for it. Yeah, 383 00:18:03.240 --> 00:18:06.640 it's proprietary. You usually need to sign a non disclosure 384 00:18:06.680 --> 00:18:08.720 agreement and NDA to get access. 385 00:18:09.480 --> 00:18:11.119 So not quite as open as some of the other. 386 00:18:10.960 --> 00:18:14.079 Stuff, right, A bit more of a hurdle for casual experimentation. 387 00:18:14.440 --> 00:18:16.519 And what about the act of tags themselves? Are there 388 00:18:16.559 --> 00:18:18.279 different types? Any clever tricks? 389 00:18:18.519 --> 00:18:21.079 Yeah, the wave Trend L series has various tags. There 390 00:18:21.079 --> 00:18:24.559 are standard personnel tags like badges, Domino style tags for 391 00:18:24.599 --> 00:18:27.640 sticking onto non metallic assets, keyfob tags. 392 00:18:27.720 --> 00:18:28.119 Uh huh. 393 00:18:28.160 --> 00:18:31.000 But one particularly clever one is the metallic asset tag. 394 00:18:32.000 --> 00:18:35.599 It's specifically designed to work even when attached directly to metal. 395 00:18:35.799 --> 00:18:37.759 How does it do that? I thought metal was bad 396 00:18:37.799 --> 00:18:38.839 for RFID. 397 00:18:39.240 --> 00:18:42.200 It usually is, especially when the tag is inside or 398 00:18:42.240 --> 00:18:45.440 sandwiched against metal. But this tag is designed to be 399 00:18:45.640 --> 00:18:48.880 affixed to the side of a metal object. Its antenna 400 00:18:48.960 --> 00:18:51.880 is tuned and positioned to radiate effectively even with the 401 00:18:51.880 --> 00:18:55.440