WEBVTT - TechStuff Gets Fit 0:00:04.519 --> 0:00:11.760 With technology with hook stuff from how stuff dot com everything. 0:00:14.360 --> 0:00:17.880 Hey there, everyone, and welcome to tech Stuff. I'm Jonathan's 0:00:17.880 --> 0:00:21.160 Trickland and on Lauren Vocbum and we're gonna track your 0:00:21.160 --> 0:00:25.040 activity with activity trackers. That's what we're talking about today. 0:00:25.040 --> 0:00:28.240 We're talking about various devices that allow you to see 0:00:28.320 --> 0:00:32.400 how much activity you've you've you've generated over a certain 0:00:32.440 --> 0:00:35.040 amount of time, and sometimes it helps you figure out 0:00:35.159 --> 0:00:38.360 how many calories you've burned or how well you've been sleeping. 0:00:38.880 --> 0:00:41.599 We want to talk about what these devices are, what 0:00:41.640 --> 0:00:43.839 they do, how they do it, and whether or not 0:00:43.880 --> 0:00:46.599 they're actually effective if you want to do something like 0:00:46.760 --> 0:00:49.360 lose weight or get fit. Yeah. Just I mean, you know, 0:00:49.400 --> 0:00:51.159 not that that many people are interested in that kind 0:00:51.159 --> 0:00:54.680 of thing, you know, Yeah, there's like maybe two right, Okay, 0:00:54.680 --> 0:00:56.520 So the last few times I've gone to C E 0:00:56.840 --> 0:00:58.960 S I have noticed really it was I think it 0:00:59.000 --> 0:01:02.920 was two years ago where that it was dramatically apparent 0:01:03.040 --> 0:01:06.399 that fitness tracking and activity tracking is a real thing. 0:01:06.480 --> 0:01:09.160 I mean, it's it's huge, huge, booming industry. Yeah. Well, 0:01:09.200 --> 0:01:11.960 I mean, you know, as as between circuitry getting smaller 0:01:11.959 --> 0:01:16.759 and uh sinking, technology improving and the software improving, and 0:01:16.840 --> 0:01:18.800 just all of these things have been coming together to 0:01:19.040 --> 0:01:24.000 create these smaller, sleeker, you know, better devices that can 0:01:24.160 --> 0:01:27.800 really help people out things that are things like interoperability 0:01:27.880 --> 0:01:31.880 to where it can interact with computers or smartphones. Not 0:01:31.880 --> 0:01:35.160 not every device does that. Let's be clear about that. 0:01:35.200 --> 0:01:37.000 There are a lot of devices out there that have 0:01:37.160 --> 0:01:39.760 kind of a limited use like that. Maybe they just 0:01:39.800 --> 0:01:42.279 sink with a computer, or maybe it's just a standalone device, 0:01:42.520 --> 0:01:45.560 but a lot of them do sync up with more 0:01:45.600 --> 0:01:47.360 than one device. You could do it with a smartphone 0:01:47.400 --> 0:01:50.840 application or or a computer or other things as well, 0:01:51.120 --> 0:01:53.320 and they'll let you They'll let you up port port 0:01:53.400 --> 0:01:55.960 whatever data you record into different apps, so that if, 0:01:55.960 --> 0:01:58.080 for example, you're into this kind of thing and you 0:01:58.120 --> 0:02:00.480 have a favorite app you can you can use that 0:02:00.520 --> 0:02:03.760 one to crunch your numbers rather than whatever other proprietary 0:02:03.800 --> 0:02:06.480 thing they have created. Right, Right, So this gives you 0:02:06.520 --> 0:02:09.840 a chance to, uh, to really keep a good look, 0:02:09.919 --> 0:02:11.840 you know, get a really good look at how much 0:02:11.880 --> 0:02:15.640 activity you are you have throughout a given amount of time, 0:02:15.680 --> 0:02:18.200 like a week or a day. So you might say, 0:02:18.240 --> 0:02:20.600 all right, I want to set a goal for myself 0:02:20.720 --> 0:02:24.080 and this device will help me measure up against that 0:02:24.120 --> 0:02:26.560 goal and decide, you know, am I am I meeting 0:02:26.560 --> 0:02:29.120 my goal? Do I need to uh to crank up 0:02:29.160 --> 0:02:31.240 the activity? Do I need to maybe you know, do 0:02:31.360 --> 0:02:34.240 a three mile jog in the morning in order to 0:02:34.320 --> 0:02:36.760 hit what my goals are? Do I need to UM 0:02:37.080 --> 0:02:40.280 to scale back or for for for hardcore trainers, am 0:02:40.280 --> 0:02:42.760 I running my heart rate too hard? Yeah? Yeah, So 0:02:43.360 --> 0:02:45.519 it all depends on what device you have, whether or 0:02:45.560 --> 0:02:48.120 not you can actually do these things, because, like we said, 0:02:48.120 --> 0:02:52.920 not every device does everything. In fact, depending upon what 0:02:53.000 --> 0:02:55.359 you want, that's going to really guide your choices when 0:02:55.400 --> 0:02:58.400 it comes to picking an activity tracker. If you're interested 0:02:58.440 --> 0:03:00.600 in something like that, absolutely and is um there's a 0:03:00.600 --> 0:03:02.800 lot of really terrific reviews out there on the internet. 0:03:02.919 --> 0:03:05.800 We'll mentioned at least one good site to go to 0:03:05.960 --> 0:03:08.800 later on in the podcast. Yeah, there's I came across 0:03:08.880 --> 0:03:11.040 lots and lots of them. And it's interesting too because 0:03:11.080 --> 0:03:14.959 you can see where the different preferences come into play, 0:03:15.000 --> 0:03:18.480 because one reviewer might say, well, you know, X is 0:03:18.520 --> 0:03:22.080 the best activity tracker because it does things this way, 0:03:22.160 --> 0:03:23.679 and someone else will say, no, no no, no, why is 0:03:23.720 --> 0:03:25.959 the best activity tracker because it does things in this 0:03:26.040 --> 0:03:28.520 other way, and it's just because it appeals to that 0:03:28.560 --> 0:03:32.760 particular person a very personal choice. Right So, so that's 0:03:32.760 --> 0:03:34.480 one thing you can get you can walk away with 0:03:34.639 --> 0:03:36.440 right now, is that we're not gonna at the end 0:03:36.440 --> 0:03:38.440 of this podcast. It's not like we're gonna say the 0:03:38.480 --> 0:03:41.480 best activity tracker is blah blah blah, because it all 0:03:41.560 --> 0:03:44.920 depends on what you want to get out of it now. Frankly, 0:03:45.040 --> 0:03:47.320 I think if you are looking at one of these things, 0:03:47.360 --> 0:03:48.720 the thing you really want to get out of it 0:03:48.840 --> 0:03:52.280 is is making sure that you are living a healthy lifestyle. 0:03:53.280 --> 0:03:55.200 And most of the ones that are on the market 0:03:55.280 --> 0:03:58.360 right now will help you do that, depending on how 0:03:58.480 --> 0:04:01.800 you use it. It's it's not magic device that automatically 0:04:01.800 --> 0:04:05.680 turns you into a fit pro athlete right now. Now. 0:04:05.720 --> 0:04:07.280 You have to you have to have your own personal 0:04:07.280 --> 0:04:11.600 sense of motivation about exercising first. Probably obtaining a fitness 0:04:11.640 --> 0:04:13.720 tracker is going to be one of the steps that 0:04:13.760 --> 0:04:17.200 you're you know, carrying out in this motivation um and 0:04:17.200 --> 0:04:21.040 and study studies have shown um that that that just 0:04:21.240 --> 0:04:23.640 mindfulness about this kind of thing can really help you 0:04:23.680 --> 0:04:28.280 out from lots lots of different corners of health and 0:04:28.320 --> 0:04:32.400 fitness when when you are given the power to track 0:04:32.480 --> 0:04:34.520 your own data and to kind of take it into 0:04:34.560 --> 0:04:36.559 your own hands like that, maybe gamify at a tiny 0:04:36.560 --> 0:04:40.240 bit um you, it really helps you out right. There's 0:04:40.279 --> 0:04:43.840 an expert, her name's Dina Bravada. I'm sure you ran 0:04:43.920 --> 0:04:46.960 across her name several times as well, because it's all 0:04:46.960 --> 0:04:51.479 over the place in the research on activity tracking, and 0:04:51.800 --> 0:04:55.159 she has said that there there is a bit of 0:04:55.200 --> 0:04:58.880 a bias that's present with activity trackers in the sense 0:04:58.960 --> 0:05:02.080 of the people who who are interested in them. She 0:05:02.160 --> 0:05:05.240 says that here's a quote. Often those kind of programs 0:05:05.240 --> 0:05:08.160 have been criticized because they attract people who are already 0:05:08.160 --> 0:05:11.400 physically active. In general, there are two categories of people 0:05:11.440 --> 0:05:13.920 who use these trackers, those who are told to wear 0:05:13.960 --> 0:05:16.679 them by a doctor because of an underlying health problem 0:05:16.920 --> 0:05:18.840 and those who are really active and just get a 0:05:18.920 --> 0:05:21.720 kick out of knowing their data. Now, none of that 0:05:21.960 --> 0:05:26.160 is a smack against these activity trackers and whether or 0:05:26.240 --> 0:05:29.240 not they are effective in what they do. She is 0:05:29.279 --> 0:05:32.080 simply saying that this is the person side of that equation, 0:05:32.400 --> 0:05:35.599 not the technology side of that equation. So let's assume 0:05:35.680 --> 0:05:37.720 that at least some of you guys out there listening 0:05:37.760 --> 0:05:40.920 are very much interested in this kind of stuff, and 0:05:41.440 --> 0:05:43.640 you are either interested in just knowing how they work 0:05:43.640 --> 0:05:45.880 in general, or you're actually thinking, hey, I would kind 0:05:45.880 --> 0:05:49.200 of like to look into one of these How do 0:05:49.279 --> 0:05:53.120 they track activity? What exactly is being tracked? And what 0:05:53.240 --> 0:05:56.000 other features might I be interested in if I want 0:05:56.040 --> 0:05:58.479 to get one of these things myself. So I thought 0:05:58.480 --> 0:06:00.799 we'd talked a little bit about some of the basic 0:06:00.920 --> 0:06:05.720 technologies that you find inside some of these trackers, all right, 0:06:05.760 --> 0:06:09.560 because these little these little bitty watch sized or bracelet 0:06:09.640 --> 0:06:12.960 sized or clips clips, you know, you have very very 0:06:13.000 --> 0:06:16.160 small devices these days. You can pack a lot of 0:06:17.080 --> 0:06:21.040 tracking devices into them. Yeah, the sensors that are available 0:06:21.120 --> 0:06:23.560 now really boggle the mind. And like we said, I 0:06:23.600 --> 0:06:25.400 don't think there is a device out there that has 0:06:25.480 --> 0:06:27.719 every single version of what we're about to talk about. 0:06:27.760 --> 0:06:29.800 But they I have not seen one. Yeah, but but 0:06:29.920 --> 0:06:31.839 many of them have several some of them only have 0:06:32.200 --> 0:06:34.880 one or two some and it may be that the 0:06:34.880 --> 0:06:37.760 way that they're packaged is very attractive, but they but 0:06:37.960 --> 0:06:41.960 from a technological point of view, they are comparatively simple. 0:06:42.640 --> 0:06:46.320 But I think one very basic technology we can talk 0:06:46.360 --> 0:06:48.960 about that you can find and in fact, some people 0:06:48.960 --> 0:06:50.840 will argue that this is really all you need if 0:06:50.880 --> 0:06:54.440 you just want to track some basic activity. Is a predometer, right, 0:06:54.520 --> 0:06:56.960 and these have been mechanical predometers. I believe it's been 0:06:56.960 --> 0:07:01.040 around since the nineteen sixties. And they hypothetic like this 0:07:01.120 --> 0:07:04.520 is this is tenuous, tenuous reportage. But but some people 0:07:04.560 --> 0:07:07.200 say that the da Vinci or Thomas Jefferson came up 0:07:07.200 --> 0:07:10.360 with the idea many many moons ago. Yeah, that's a 0:07:10.560 --> 0:07:13.960 pretty big spread in years if I know my history. 0:07:14.000 --> 0:07:18.280 But yeah, and I do. But yeah, a podometer today, 0:07:18.920 --> 0:07:21.760 it takes a pretty basic form. Usually you have some 0:07:21.840 --> 0:07:24.160 sort of display that's going to tell you how many 0:07:24.200 --> 0:07:26.600 steps you have taken. That's what a podometer does. It's 0:07:26.600 --> 0:07:28.760 supposed to measure how many steps you take. So how 0:07:28.760 --> 0:07:32.160 does it do that. It's essentially counting the number of 0:07:32.160 --> 0:07:35.679 times your foot makes impact with the ground. And really 0:07:35.760 --> 0:07:39.240 that means it's just measuring various shaking of your body. 0:07:39.320 --> 0:07:42.000 So if you are in a car and you're on 0:07:42.040 --> 0:07:44.760 a particularly bumpy road, it's going to start registering that 0:07:44.800 --> 0:07:48.840 as footsteps if it's particularly bumpy, right, or or if 0:07:48.840 --> 0:07:50.560 you hold it in your hand and sway your arm 0:07:50.600 --> 0:07:53.080 back and forth, you would totally fool the device, right, 0:07:53.200 --> 0:07:56.560 not that I know that from prior get Fit corporate 0:07:56.800 --> 0:07:59.800 UM programs that I have cheated a tiny bit on right, Uh, 0:08:00.480 --> 0:08:03.400 if you're not benefiting anyone at that point, let's let's 0:08:03.400 --> 0:08:07.160 stop the cheating. Hey, Lauren, aren't you the team captain 0:08:07.200 --> 0:08:12.280 of our own departmental cheating. I was demonstrating to people 0:08:12.320 --> 0:08:15.840 how the device worked, and I was accused of using 0:08:15.880 --> 0:08:19.440 that as a way of boosting your numbers. All right, 0:08:19.480 --> 0:08:21.360 team captain, Now I've learned a little more about you. 0:08:21.480 --> 0:08:24.720 So anyway, what's what's going on here is inside the 0:08:24.720 --> 0:08:29.400 pedometer you have a a system that essentially forms a switch. 0:08:29.680 --> 0:08:32.320 All right, You've got you've got a weight, and when 0:08:32.320 --> 0:08:36.560 that weight moves it can make a connection that closes 0:08:36.600 --> 0:08:38.920 a switch and counts as a step. And then when 0:08:38.960 --> 0:08:42.160 it moves away that and hits it again, that counts 0:08:42.200 --> 0:08:45.320 as another step. So every time this weight disconnects and 0:08:45.320 --> 0:08:50.720 then reconnects with a contact, a step is registered. And uh, 0:08:50.960 --> 0:08:52.440 you know, it used to be that these were pretty 0:08:52.480 --> 0:08:55.360 big mechanical things where you had a weight suspended on 0:08:55.720 --> 0:08:58.720 like a spring or a pendulum or a small ball 0:08:58.760 --> 0:09:00.840 that could roll back and forth, a cross a tiny track. 0:09:01.040 --> 0:09:03.880 Right now, we're talking about things that are on the 0:09:03.880 --> 0:09:08.200 the micro structure level. But it's still this basic mechanical 0:09:08.280 --> 0:09:12.320 motion of making a contact, breaking a contact, and that 0:09:12.400 --> 0:09:14.439 every time you do that break is what counts is 0:09:14.480 --> 0:09:17.680 a step. Yeah, so uh, it's still still the same 0:09:17.720 --> 0:09:21.240 mechanical approach. It's just now it's much much, much, much 0:09:21.280 --> 0:09:23.680 smaller than what it used to be back in the 0:09:23.679 --> 0:09:28.320 sixties or earlier. If we are to believe that some 0:09:28.400 --> 0:09:32.240 of our our genius ancestors came up with this idea, 0:09:32.400 --> 0:09:35.760 it was probably Tesla, yeah, and it always ends up 0:09:35.760 --> 0:09:39.240 being Tesla, although his probably would also bring down an airplane. 0:09:39.720 --> 0:09:43.560 So uh. Anyway, the old predometers, if you would actually 0:09:43.600 --> 0:09:45.000 pick one up and shake it, you might hear a 0:09:45.040 --> 0:09:48.280 clicking noise, and that's the little switch that's inside it. Again, 0:09:48.320 --> 0:09:50.400 it might be that little ball if it's using that 0:09:50.440 --> 0:09:54.280 particular kind of technology. The newer ones, again, are all 0:09:54.360 --> 0:09:57.240 chip based. They don't have those little those They don't 0:09:57.240 --> 0:09:59.520 have things large enough to make that kind of clicking 0:09:59.520 --> 0:10:02.200 noise unless you've been shaking it way too hard, in 0:10:02.200 --> 0:10:04.280 which case something is probably loose and it may not 0:10:04.360 --> 0:10:07.959 be working at all. Anymore. But anyway, that's your very 0:10:07.960 --> 0:10:12.360 basic pedometer. So it's not terribly accurate in the sense 0:10:12.440 --> 0:10:16.520 that it can't it can't distinguish between different kinds of 0:10:16.559 --> 0:10:18.679 impact and say, oh, well that was definitely a step 0:10:18.840 --> 0:10:21.920 versus that was just a bump, right, um. But they 0:10:22.320 --> 0:10:25.120 are getting a little bit more technologically advanced in that. 0:10:25.120 --> 0:10:28.880 Originally you had to use the counter and combine that 0:10:28.920 --> 0:10:31.400 with a calculation of how long each of your steps 0:10:31.400 --> 0:10:33.560 were in order to calculate distance. These days, they can 0:10:33.559 --> 0:10:36.319 do that for you with onboard computers. Sure. Oh so 0:10:36.360 --> 0:10:39.080 instead of saying like, oh, my stride is this many 0:10:39.120 --> 0:10:42.199 inches long, therefore this many steps and having to get 0:10:42.200 --> 0:10:44.680 a little bit of math. By the way, I said inches, 0:10:44.720 --> 0:10:47.680 and I would say miles because I live in America 0:10:47.720 --> 0:10:50.120 and that's what we do. But centimeters meters that kind 0:10:50.120 --> 0:10:53.000 of thing, right, it would It does the math depending 0:10:53.000 --> 0:10:57.360 on what scale you're using. The more advanced version of 0:10:57.400 --> 0:11:02.560 this sort of approach is the accelerometer. Now, an accelerometer 0:11:02.600 --> 0:11:04.840 is different. It's not got a little switch that's just 0:11:05.720 --> 0:11:10.360 registering a change. Yeah, it's not just like that was 0:11:10.400 --> 0:11:14.880 a shake. It's actually detecting changes in velocity. Uh. Now, 0:11:15.000 --> 0:11:20.400 velocity is speed plus direction. So if you alter that velocity, 0:11:20.440 --> 0:11:24.840 then you are talking about an accelerating force. So, for example, 0:11:24.880 --> 0:11:27.679 when you start, when you start from a standstill and 0:11:27.720 --> 0:11:31.800 you start moving into a run, that's accelerating. You're accelerating 0:11:31.800 --> 0:11:33.640 into a run. Now, once you hit top speed, you 0:11:33.640 --> 0:11:36.040 are no longer accelerating. You may be maintaining a speed. 0:11:36.400 --> 0:11:40.720 But accelerat arometers are all meant to detect these changes 0:11:40.760 --> 0:11:44.960 in velocity. And you've got two basic categories of accelerometers. 0:11:44.960 --> 0:11:47.480 There are many types of accelerometer rometers, but they fall 0:11:47.520 --> 0:11:51.880 into two basic categories. They're static accelerometers. Now, these measure 0:11:51.960 --> 0:11:58.880 a static uh form of acceleration. For instance, gravity, Gravity 0:11:59.200 --> 0:12:02.920 is static, it's not changing when you are on the 0:12:02.960 --> 0:12:05.079 surface of the Earth. It's going to remain the same. 0:12:05.559 --> 0:12:09.520 And so you might wonder why would you need a 0:12:09.520 --> 0:12:13.880 stack accelerometer. It's so that you can determine the rotation 0:12:14.040 --> 0:12:16.800 of a device in respect to the surface of the Earth. 0:12:17.160 --> 0:12:20.480 Very important for something like a smartphone, where you are 0:12:20.520 --> 0:12:22.600 holding the smartphone, you move it from portrait to landscape, 0:12:23.600 --> 0:12:27.800 the static accelerometer is what tells it, oh, the the 0:12:28.240 --> 0:12:31.680 the attitude of this phone has changed not that you're 0:12:31.760 --> 0:12:34.439 giving off attitude. Necessarily, you might be texting I don't 0:12:34.800 --> 0:12:38.000 I usually amy, this is fair, but and rather the 0:12:38.080 --> 0:12:40.560 position in relative to the surface of the earth. So 0:12:40.600 --> 0:12:43.040 if you were to turn it into the landscape mode, 0:12:43.240 --> 0:12:48.400 the screen would would change to reflect that. That's why 0:12:48.360 --> 0:12:53.440 a stack accelerometer is useful. For dynamic accelerometers, they measure 0:12:53.600 --> 0:12:57.440 changes in motion of the accelerometer itself. So the accelerometer 0:12:57.520 --> 0:12:59.800 is part of the larger device. So this is too 0:13:00.120 --> 0:13:03.240 measure the changes in acceleration of that device, not in 0:13:03.320 --> 0:13:05.800 respect to the ground, but just within that device itself. 0:13:06.120 --> 0:13:10.320 So you might have both types in a fitness tracker. 0:13:10.440 --> 0:13:12.480 If the fitness tracker has some sort of screen that 0:13:12.520 --> 0:13:16.080 will rotate depending upon how you're holding your arm. Let's 0:13:16.080 --> 0:13:18.400 say it's a it's a screen that's on a wristband 0:13:18.480 --> 0:13:20.959 or something that's like a watch, and then it might 0:13:20.960 --> 0:13:23.960 have a stack accelerometer and a dynamic one. The dynamic 0:13:23.960 --> 0:13:26.720 one would be more useful for it to detect changes 0:13:26.760 --> 0:13:31.120 in velocity and thus translate that into motion that the 0:13:31.240 --> 0:13:35.319 user is moving around, and that means that the user 0:13:35.480 --> 0:13:39.320 is burning calories and is there's there's activity going on, 0:13:39.400 --> 0:13:42.960 so that's part of the data that this device will 0:13:43.280 --> 0:13:47.839 gather and analyze to translate that into this is what 0:13:47.880 --> 0:13:50.120 your body is doing right right, and we should we 0:13:50.160 --> 0:13:52.720 should add at this point that UM, that a lot 0:13:53.080 --> 0:13:56.079 of the actual output of data that these devices are 0:13:56.120 --> 0:13:59.080 giving you is not UM. Is not the actual data 0:13:59.120 --> 0:14:00.920 that these sensors are making in a lot of it 0:14:01.040 --> 0:14:04.680 is UM really fancy algorithms. And and thank you to 0:14:04.760 --> 0:14:06.719 Peter on Facebook for writing it and telling me that 0:14:06.760 --> 0:14:09.720 I totally say that wrong sometimes because I do UM. 0:14:09.760 --> 0:14:13.360 You know, it's it's it's approximating more complex technology, or 0:14:13.400 --> 0:14:16.960 it's UM gathering together a bunch of these little tiny 0:14:17.080 --> 0:14:20.240 numbers and figuring out something useful that I can tell 0:14:20.320 --> 0:14:23.320 you in return, exactly taking this raw data and making 0:14:23.320 --> 0:14:26.160 it meaningful to us, because otherwise we really what an 0:14:26.200 --> 0:14:29.640 accelerometer would tell you is how much voltage it was generating, 0:14:29.720 --> 0:14:31.960 which doesn't help us at all. That doesn't that's not 0:14:32.080 --> 0:14:35.160 meaningful to at least it's not meaningful to me, and 0:14:35.200 --> 0:14:38.880 I suspect not to Lauren. Uh. Some of you electricians 0:14:38.880 --> 0:14:40.800 out there might say, no, I totally get it, but 0:14:40.880 --> 0:14:42.640 the rest of us are thinking, no, we need this 0:14:42.680 --> 0:14:45.280 translated into something that makes sense like how many calories 0:14:45.280 --> 0:14:46.840 did I burn or how many steps did I take 0:14:46.920 --> 0:14:50.400 or how far did I go? So that's that's the 0:14:50.480 --> 0:14:56.440 basic uh two kinds of accelerometers. The the types underneath 0:14:56.440 --> 0:15:01.000 those are how they detect these changes in the law city. UH. 0:15:01.000 --> 0:15:03.840 And there's a lot there's there are capacitive ones, there's 0:15:03.880 --> 0:15:08.240 piece of electric, there's pizza resistive, there's magneto resistive, there's 0:15:08.280 --> 0:15:11.440 heat transfer. There's lots of different types. There's some that 0:15:11.560 --> 0:15:14.840 use light. But the one that I think, the type 0:15:14.840 --> 0:15:16.960 that's used the most in electronics as far as I 0:15:17.000 --> 0:15:20.680 can tell, is the capacitive type. And so you might 0:15:20.680 --> 0:15:24.720 wonder how does this work. You've got some micro structures 0:15:24.760 --> 0:15:28.240 within a chip, all right. One of them is you've 0:15:28.280 --> 0:15:31.720 got a housing which is is mounted directly to whatever 0:15:31.720 --> 0:15:35.800 the devices on a substrate. So this housing uh will 0:15:35.880 --> 0:15:39.800 move in uh the same way that the device itself moves. 0:15:40.000 --> 0:15:44.120 It's it's dependent upon that. Then you've got a little 0:15:44.280 --> 0:15:49.760 micro structure inside of it that can move freely uh 0:15:49.840 --> 0:15:53.200 in respect to the housing. So if you were to 0:15:53.240 --> 0:15:56.240 shake the device, the micro structure would lag a little 0:15:56.240 --> 0:15:58.400 bit and then pick up that motion, just as if 0:15:58.440 --> 0:16:00.640 you had a spring with a ball on the end, 0:16:00.640 --> 0:16:02.240 and you started moving the top of the spring and 0:16:02.280 --> 0:16:03.720 then the ball would start to move. It's this whole 0:16:03.720 --> 0:16:06.480 momentum thing that's coming up. You've also got these other 0:16:06.520 --> 0:16:09.800 little bitty structures, these micro structures inside this this tiny 0:16:09.840 --> 0:16:12.760 little chip, and I'm talking about teeny tiny we're we're 0:16:12.880 --> 0:16:15.760 tug on the level of microns. Yeah, these are all 0:16:15.800 --> 0:16:19.280 called a microelectro mechanical systems. Yeah, they're they're so small 0:16:19.440 --> 0:16:21.840 that you have to have an automated system to etch 0:16:21.960 --> 0:16:25.520 them onto chips because there's no human with the precision 0:16:26.440 --> 0:16:30.600 necessary to make these things so super tiny. But as 0:16:30.640 --> 0:16:33.560 the microstructure moves, it starts to move between these plates 0:16:33.600 --> 0:16:36.840 that have capacitance. That changes the capacities. It causes current 0:16:36.920 --> 0:16:39.920 to flow, and measuring the current tells you how much 0:16:40.000 --> 0:16:43.560 this device is moving. And by putting these chips in 0:16:43.720 --> 0:16:47.600 different arrangements within a device, you can track different types 0:16:47.640 --> 0:16:50.760 of movement. Because you can only detect movement along one 0:16:50.840 --> 0:16:54.400 axis with a with a very simple accelerometer. Uh, that 0:16:54.440 --> 0:16:58.720 means that you can detect movement along one line of 0:16:59.080 --> 0:17:02.280 one one vector. Really you can't anything up beyond that. 0:17:02.320 --> 0:17:06.440 It wouldn't detect So let's say left right versus up down. Uh. 0:17:06.480 --> 0:17:09.200 If you had three of these accelerometers or to two 0:17:09.240 --> 0:17:12.560 axis accelerometers that were at right angles to one another, 0:17:12.840 --> 0:17:15.240 you could then detect things like along the x axis, 0:17:15.280 --> 0:17:18.199 the y axis, and the z axis. So three axis 0:17:18.240 --> 0:17:21.080 accelerometers what we call those, and those are that those 0:17:21.080 --> 0:17:22.640 are the popular ones and in all of the new 0:17:22.640 --> 0:17:24.520 devices coming out these days. Yeah, and it's also the 0:17:24.560 --> 0:17:27.560 kind of stuff you find in things like video game controllers. Uh. 0:17:27.600 --> 0:17:29.879 And it's some of them you hear about six axis, 0:17:29.920 --> 0:17:33.800 which is really just getting more specifically precise. Um. Yeah, 0:17:33.880 --> 0:17:36.359 and so this will detect those changes in motion and 0:17:36.400 --> 0:17:40.399 be able to translate that into again meaningful data once 0:17:40.440 --> 0:17:44.640 you run those raw numbers through whatever software you've got. Uh. 0:17:44.760 --> 0:17:49.280 So those are your two basic ways of detecting motion 0:17:49.480 --> 0:17:53.080 from a purely like this device is moving kind of perspective. 0:17:53.080 --> 0:17:55.400 There are other things that will also detect motion, which 0:17:55.440 --> 0:17:58.080 we'll talk about as well in a little bit. Before 0:17:58.080 --> 0:17:59.440 I get to that, though, I do need to say 0:17:59.440 --> 0:18:01.720 there's a couple of are things that are important about accelerometers. 0:18:01.760 --> 0:18:05.800 One is that sensitivity of an accelerometer is extremely important. 0:18:06.160 --> 0:18:10.040 The more sensitive and accelerometer is, then the more it 0:18:10.080 --> 0:18:14.080 will generate a larger charge in our larger change in 0:18:14.119 --> 0:18:17.560 signal rather for a given change and acceleration compared to 0:18:17.640 --> 0:18:22.120 a less sensitive chip. So these bigger changes are easier 0:18:22.119 --> 0:18:24.440 to measure, and that gives the device a better idea 0:18:24.440 --> 0:18:28.200 of the actual changes in acceleration. So, in other words, 0:18:28.560 --> 0:18:30.720 if you if you make it so that these changes 0:18:30.760 --> 0:18:33.720 are are huge, uh, it can really narrow down the 0:18:33.720 --> 0:18:36.800 parameters of what that change means, and it can be 0:18:36.920 --> 0:18:40.919 more precise in thinking this is more likely an actual 0:18:41.000 --> 0:18:44.520 step versus someone just bump their knee on their desk 0:18:44.560 --> 0:18:46.920 and went out, yeah, yeah, that the technology is getting 0:18:46.960 --> 0:18:50.160 a lot better at um weeding out those false positives exactly. 0:18:50.440 --> 0:18:52.000 And then there are other things you've got to keep 0:18:52.000 --> 0:18:55.440 in mind, like what's the maximum swing of your accelerometer 0:18:55.760 --> 0:18:58.840 that's telling you how much force it can measure or 0:18:58.840 --> 0:19:01.639 how much of a change in nextceleration it can measure. Uh, 0:19:01.680 --> 0:19:04.439 this is really more important if you are designing something 0:19:04.480 --> 0:19:07.160 that moves really really fast and comes to really fast 0:19:07.200 --> 0:19:10.240 stops like a jet, not so much with a person, 0:19:10.320 --> 0:19:13.439 because while you feel you might be fast compared to 0:19:13.480 --> 0:19:16.440 other stuff, you're really slow less less fast than the jet. 0:19:16.640 --> 0:19:18.600 And then you have bandwidth, which is how many times 0:19:18.600 --> 0:19:22.000 a second you can take a reliable acceleration reading. Uh. 0:19:22.040 --> 0:19:25.240 And we don't need anything too precise for human activity 0:19:25.280 --> 0:19:28.080 because again we're not moving that quickly. But these are 0:19:28.119 --> 0:19:31.680 things that are important in accelerometers in general. Uh. We've 0:19:31.680 --> 0:19:33.560 got a lot more to talk about as far as 0:19:33.600 --> 0:19:37.760 the sensors go within this these uh, these activity trackers. 0:19:37.800 --> 0:19:39.680 But before we get into that, let's take a quick 0:19:39.720 --> 0:19:43.240 moment to thank our sponsor. Alright, we're back. So, so 0:19:43.280 --> 0:19:46.040 we've talked about accelerometers and photometers, there is one other 0:19:46.080 --> 0:19:49.320 way the device can track whether or not you've moved around, right, 0:19:49.359 --> 0:19:53.000 Because accelerometers are really great fear for example, on a treadmill, Yeah, 0:19:53.080 --> 0:19:56.320 fantastic because it doesn't have to track your location. It 0:19:56.400 --> 0:19:59.360 just has to track what you are doing. But if 0:19:59.400 --> 0:20:02.320 you have a EPs receiver in your activity tracker, and 0:20:02.400 --> 0:20:05.560 some of them do with them, you can actually track 0:20:05.920 --> 0:20:09.479 where you are in relation to I don't know anything 0:20:09.520 --> 0:20:11.920 else on the planet. But these are not so useful 0:20:12.280 --> 0:20:14.159 if you're just running on a treadmill. No, but but 0:20:14.200 --> 0:20:17.360 they are very much more accurate for calculating the distance 0:20:17.359 --> 0:20:20.760 that you have gone, right. Yeah. So GPS in general, 0:20:20.840 --> 0:20:24.119 this Global Positioning system, Uh, what what's going on is 0:20:24.119 --> 0:20:27.080 You've got the satellites that are beaming down information here 0:20:27.240 --> 0:20:29.640 to the planet and network of twenty four of them. Yeah, 0:20:30.080 --> 0:20:34.760 so your GPS receiver receives this these signals from the 0:20:34.840 --> 0:20:38.560 various satellites. Now, each satellite is sending its own unique 0:20:38.600 --> 0:20:41.560 signal down that has essentially a time stamp on it, right, 0:20:41.600 --> 0:20:44.800 and they're all synchronized. Right, So you're getting these different 0:20:45.080 --> 0:20:48.280 signals all at the same time from at least usually 0:20:48.320 --> 0:20:52.160 at least three satellites. Four works best, four works best, 0:20:52.480 --> 0:20:54.919 and and so your device gets these different signals from 0:20:54.960 --> 0:20:58.200 these different satellites, and by measuring how long it took 0:20:58.400 --> 0:21:01.399 the signal from each satellite to get to that uh, 0:21:01.440 --> 0:21:05.040 that device it just compares that against its own its 0:21:05.040 --> 0:21:09.080 own little internal clock. It can tell you where you 0:21:09.119 --> 0:21:11.120 are in the surface of the Earth. Technically you could 0:21:11.160 --> 0:21:13.920 be in one of two places, but that second places 0:21:14.080 --> 0:21:17.440 inside the earth, So we pretty much just say that's 0:21:17.520 --> 0:21:20.520 not it cuts that right out. Yeah, and that this 0:21:20.600 --> 0:21:26.120 was originally military technology, I believe in the seventies and nineties, 0:21:26.119 --> 0:21:30.040 in fact, when when we first started getting consumer access 0:21:30.520 --> 0:21:35.600