EEVblog #945 - Thermal Powered Smartwatches Are GIMMICKS!

hi we've got another crowdfunding campaign for you yes on the choice of Champions indiegogo flexible funding quite a few people asked me to have a look at this one and see if it all adds up let's take a look at it it is the matrix power watch the Smart Watch powered by you and look at this looks fantastic I want one pretty Jersey and yeah look at this a SmartWatch that could be the harbinger and the future Matrix Industries wants to free us from battery woes wearables can and should power themselves good on your I Triple E spectrum Gizmodo high power watches unique thermoelectric technology gives it a big advantage when it comes to accuracy there's a new SmartWatch in town that's ready to make charging complete non concern is eternal battery life long enough for you the dream of the no charge watch and on and on and on it goes yes it's a watch powered by a thermoelectric generator and it can also measure calories via the thermoelectric generator as well by measuring your body heat output so yep it's a smart watch with a thermoelectric generator a tag in there and where that scene tags on the eevblog before nothing special and there's nothing new here at all several companies have actually are produced thermoelectric generator watches a long time ago but I think there's a reason why they don't make them anymore as we'll see now this is actually done by an impressive our team and you can go in and see their BIOS and everything else these are all University professors PhD researchers in thermoelectric thermo electronic technology so these guys know what they're doing right so I have no problems with the team whatsoever and you know this is not a scam right this of course you can power a watch from a thermoelectric generator but this is the first SmartWatch on the market Albert a relatively simple SmartWatch it doesn't have a heart rate monitor or anything like that it's got another fancy stuff it's got no Auto notification from your smartphone and things like that but yes it does have Bluetooth and an app and you can actually sync it up but it do most of your traditional SmartWatch functions and things like that unfortunately so it's basically a watch with a stopwatch and the whole key to it is that it can measure your calories because it's using the heat output from the thermoelectric generator and hang on what's this certified by arrow electronics this entrepreneur received a design review with arrow to ensure the campaign is ready for production IndieGoGo and arrow electronics are proud to offer this resource to help entrepreneurs bring products to life well that ticks all the boxes doesn't it I mean arrow huge company they have obviously vetted this thing and it's fine or have they know if you actually go into arrow what is arrow certification they do a design for manufacture analysis ie the bomb and stuff like that and they're actually boasting matrix have actually appeared on the eevblog forum to try and explain the cells but they're not answering questions and they've said they seem proud that arrow was certified this thing because they reviewed the schematic well sorry no it doesn't work like that there of course you can make a watch powered from a thermoelectric generator and get it made it's no big deal the whole point of this thing is does it have a point actually is there an advantage to powering a watch from a thermoelectric generator or is it just a gimmick and arrow have not that's not their job to actually verify that thing at all whether or not it's worthwhile powering it from a tag like this so yeah they're just trying to you know make it look fancy pantsy that they're certified by arrow doesn't really mean much our world has an ever-increasing thirst for energy our machine here we go it's feeling good video time yet most of the energy we use is wasted twice over 30 trillion watt hours of heat we are wasted by power plants alone enough to power the entire world and our environment is part of the collateral damage by cyber firemen billion batteries are thrown away in landfills every year billion at matrix we wanted to create technology that makes the way we use energy good on yet efficient and more intimate awesome you wanted to start with a problem everyone has experienced firsthand feeling frustrated when your electronic device runs out of power when you need it the most just remain in evasion to solve this problem and that god is excited to solve it using our thermoelectric technology whoo after five years and several prototypes we're introducing what a workers product fantastic matrix power launch it's a SmartWatch the powered by you let's have my mouse by converting your own body heat to electric power and the savories batteries never have to charge it never have to child box comes alive because it's powered by you we've done most of the hard work you have a few dozen prototypes and a ton of data so we know it works the power watch has been vetted and certified by arrow electronics so as I mentioned they actually joined the eevblog forum I guess to try and defend themselves and that's great we love it when companies join the forum and share data because as you saw in the video they have tons of data that proves it works well yeah we know it works it's a thermoelectric generator and a watch you know it's definitely going to work but is it practical and they actually seemed quite offended that anyone would dare question the practicality of the product and whether or not it's the thermoelectric generator is simply a gimmick and we asked them several people on the forum including myself asked time and time again just provide the data will change your minds just give us the data and nope they simply refuse to give it so yeah you can see what's coming but hey all we need is a couple of bits of data on this thing to allow us to do some quantitative analysis on to see if it's a viable and practical product or and whether or not it's just a gimmick or not so we have that data they've actually provided that in various news stories and other things like that and their IndieGoGo comments so let's go so let's run the numbers shall we back of the envelope ballpark stuff actually we're better than ballpark because we've got some really good knowing numbers here so let's go through it it won't take me very long at all to show what a gimmick thermoelectric generation for watch actually is so we're the no.1 numbers that we've got the operation takes about 20 micro watts or so I got this I speculated this on the forum eevblog forum and they said yet my numbers were fine they didn't dispute that so let's go with 20 micro watts operation are the shop memory LCD they're really low power it's about 4 microts plus the Apolo ambach processor that they're using it's an ARM Cortex whatever something or other so let's take 20 micro watts they've said that is basically fine now they've released a figure for the battery inside the capacity of the battery 200 milliamp hours that's going to be a lithium-ion job' at 3.7 volts that's 740 milli watt hours capacity in the internal battery now they've also said in the comments on the IndieGoGo campaign somebody asks hey what's the power output you get from the thermoelectric generator and they said under basically best-case conditions a cold windy day during exercise they got 500 micro watts so that is presumably the generation figure that's not how much that after the losses in the DC to DC converter everything else that's generation and that's their best figure that's the best pie-in-the-sky best cased figure that they can get but we'll run with that we'll be generous we'll run with that so I've got three good known figures here now we're going to assume that it generates 50 micro watts at rest I'll give him 50 micro watts they're experts in these thermoelectric generators they're researching them manufacturing the site they know what they're doing there and you're going to be resting for about 15 hours a day because you're not going to wear it when you're sleeping you're sleeping it's going to reach thermal equilibrium so it's not going to generate any charge and nobody wears a damn watch to bed and you know you're lying on it stuck under the pier lowitz whatever it basically even if you wore it to bed it's not going to generate anything so let's see 15 hours a day 750 microwatt hours per day generation at rest and I think that's pretty generous so now we can do the calculations here let's assume that you're really active and you do one hour solid hardcore exercise a day at their best case figure of 500 microwatts okay that's 500 micro watt hours per day that equals our 1.25 million watt hours per day total if you add the rest plus the one hour of exercise a day that's and that's been generous well but you don't get a free lunch of course it has to run 24/7 let's assume it doesn't go into its deep sleep mode I want my watch to be always-on we don't look at the damn thing I want there to be time there so that's the 20 microwatts operation times 24 hours a day that's going to use 480 microwatt hours so you've got to subtract that from your 1.25 million hours here or 1250 microwatt hours per day so point seven seven milli what hours per day that you have available to store in your battery and once again I'm not including any losses in the DC to DC converter or charging process or anything like that so I'm being very generous so even if you're flogging your guts for an hour solid exercising every day and you wear it all day basically except when even even if you were sleeping then you're only going to get like less than 1 milli watt hour per day available to store the battery now I know this thing actually goes to deep sleep when you take it off so presumably it doesn't update the time or anything like that it saves all your stuff and things like that but I don't when I take a watch off I don't want it to the time to vanish I want it to be there but anyway let's assume that you're sleeping err 8 hours a day you take it off and it's going into low-power mode well you haven't got the 20 microwatts for the 24 hours you've got to subtract eight hours of sleep time but even then you know assuming it drops down to basically zero bugger all in it still doesn't change the overall calculation much so let's assume that the battery went flat in this thing but it's not supposed to because just the low-power operation plus bluetooth doesn't take a huge amount Eva it should never get flat but let's just assume it did for kicks how much would it take how long would it take to charge the internal 200 milliamp hour 740 milli watt hour capacity battery in this thing well 740 million watt hours divided by 0.77 milli watt hours per day 961 days or 2.6 years to charge this thing from flat but that's not the intention just did that for kicks the whole idea of this watch is that sort of it's supposed to generate more power by wearing it than it actually consumes and therefore you never have to change the battery but hey let's just assume that you used it as a normal watch with no Bluetooth our functionality just a normal SmartWatch again maybe it's running a little app or doing something like that at the 20 milli watt operation let's assume that it operates all day even a cr2032 single coin cell battery has got a capacity of 600 milliwatt hours at 20 microwatts a consumption that's 30,000 hours operation 1250 days three and a half years they can have powered this watch from anyway without the thermoelectric generator gimmick in it and they get three and a half years operation it just like you can buy Casio watches they get ten years operation and shelf life of the battery and for all the physical space they've taken inside this thing for the thermoelectric generator they can wacky nut much bigger battery than a cr2032 or just made it thinner but then hey they don't have a gimmick to sell it and I think a lot of people are just going to be using it as a regular watch because it's not like it has you know heart rate tracking and stuff like that or it's like a real SmartWatch and that people use it for to get you know email alerts and know call notifications and stuff like that on your watch it's got none of that because it doesn't have much in the way of SmartWatch functionality so right there as a watch that never runs got a battery it is pointless it is a gimmick but hey if you want a thermo electric charging watch just because you know it's cool or whatever okay that's fine knock yourself out but don't pretend that it's you know something special in terms of never running out of battery this watch sticking a regular coin selling it would never run out of battery anyway so let's look what happens when we add bluetooth shall we Bluetooth le is pretty low power I'm there's a TI application note which I'll link in down below where they actually do measurements on one of their Bluetooth le modules let's assume that you know that's basically as good as you can get they came out with an average figure of about 80 micro watts our consumption or there abouts with a once per second continuous connection so that's you know reasonably good but that's four times the our operating current roughly of the actual watch so you know you wouldn't want to leave that on all day every day so let's assume that you actually had it on and continuously connecting like a regular SmartWatch would connecting to your phone let's say they added these things which I think they're talking about adding you know more SmartWatch our capability in terms of you know updating your from your phone and all that sort of stuff well at 15 hours our operation then that's 1.2 million hours per day that's like you know more get in towards double ish of the energy that we're actually going to get out of the singers store and remember I was being generous with no losses so now you can probably understand why they haven't built this functionality in like continuous SmartWatch bluetooth polling because I don't think they're going to generate nearly enough power in the thermoelectric generator to keep this thing charged and to get their infinite battery life but even if you use Bluetooth continuously 24 hours a day let's have a look at what just a regular primary coin cell will get you let's say you used a bigger coin cell rather than a little wimpy 2032 let's say you used a CR 24 50 here in blue I've got the figures now that's a roundabout two thousand milli watt hours capacity let's assume that you had Bluetooth all the time 80 million watts 24 hours a day seven days a week 365 plus the twenty milli watts operation for the thin continuous none of this deep sleep rubbish you've got a hundred micro watts consumption that will still give you that battery will give you twenty thousand hours of operation or about 2.3 years why on earth would you need a thermoelectric generator to charge an internal battery it's not environmentally friendly you still got the lithium-ion battery in there it just doesn't make sense no matter how you look at this thing it is nothing more than a gimmick designed by of course professors were at the University working on thermoelectric generators they've been working on for so long as their life it's their passion hey and that's great but now they've tried to just shoehorn that technology indoor watch making it out like it's the greatest thing since sliced bread you never have to change the batteries what they freakin do just put a regular coin cell battery in there and you'll get many years of battery life your things going to watch is probably gonna break before then especially it's designed to be like an exercise watch it's like give me a break and they also claim that the watch is going to be one of the most accurate calorie counters out there because it's measuring the heat output from your wrist well I want to know exactly the data behind this and how they can prove that because I'm skeptical of that one because the autonomic nervous system as Thunderfoot is shown in his video during exercise the energy will drain out the heat will drain out of your arms and then for a while and then go back in how is this accurate how does their algorithm account for the fat you know for your body doing this based on what particular exercise you're doing I don't think it's going to be accurate at all I'd love to hear their feedback on that one I asked him on the forum and no response and before you go and say I've got some sort of calculation wrong there they have basically admitted that there's nothing wrong off my calculations I did these the forum previously they were involved in discussions I asked them to provide their data they wouldn't do it they said they'd provide it to me privately come on give me a break write the numbers add up they have confirmed them and what you might as well just stick a bloody battery in the think it's a thermoelectric generator gimmick buzz I mean this is pretty basic stuff that anyone can do and these guys know it they know that it's a gimmick and they want to get you know funding for researching further products that they want to do but hey they're taking people's money for this SmartWatch people are going Wow it never needs to change a battery when they don't realize you could have just done that anyway with a primary cell so yeah but they won't tell you that because then it wouldn't sell so can a thermoelectric generator like this actually power modern digital watch just are driving a smart memory LCD well of course it can spoiler alert I'm anyone who knows anything about thermoelectric generators modern low-power processes know this is easily possible and I'm going to demonstrate it here and we can get a few numbers now what I've got here is the art you seen this before on the blog the worth electronic design kit board I've got here is actually a linear technology board I'll link it in down below if you want to have a play around yourself this has got different energy sources a thermoelectric generator here from my cui it's just a jelly bean one I'll link in the datasheet it's got solar cells as well and piezo electric generator inputs but we've only got the thermoelectric generator actually hooked up here and here's the schematic for the circuit we're using it uses a linear technology 3801 low startup voltage DC to DC converter fairly typical in one of these thermoelectric generator applications and over here we've got an efm32 giant gecko processor this is an arm cortex m3 processor driving an LCD here batteries are disconnected of course it's are being powered from a thermoelectric generator and this multimeter here is measuring the input voltage from the thermal or the output voltage of the thermoelectric generator and this one here is measuring the output of our DC to DC converter which is normally our 3.3 volt regulated now of course it's not generating not anything in fact it's are generating a negative voltage here because the heatsink is heat and just heat up a little bit above the ambient because I've actually been playing around that putting my hand on it and the heat from my hand the energy from my hand is transferred through to the heatsink and you see that's slowly dropping back down now so it's actually working in Reverse and generating a negative voltage but of course if I put my hand on there then this top plate the positive plate will be at a higher temperature than the heatsink and it will start generating a voltage generating current and as you'll see it'll powers of the circuit so let's go and born 30 Mille volts and should get there it should get there hold on to your hat 3.3 volts bingo there you go it's at 19.7 degrees see here in the lab by the way if you just wanted to know what that's a 68 Fahrenheit for you Yanks and of course if I take that away you'll see it start to drop but I've got some output capacitance on here small amount of output capacitance and of course this micro can work down to lower voltages so you'll see it eventually fade away like that as the thermoelectric generator reaches thermal equilibrium again it'll go back down to zero so bingo just using a jellybean thermoelectric generator we can easily power an arm cortex m3 processor I'll be at a nice little efm32 low-power job' here and an LCD no worries whatsoever hey but they use an ink display they're even lower power than these LCDs and kind of effectively so let's try that so what I've got here is an EF m8 sleepy B and it actually uses a I'm not sure the resolution I think it's hundred and twenty eight by twenty one hundred and twenty eight they're using matrix are using the 240 by 240 sharp memory LCD but it's the same sharp memory LCD and once again I can put my hand on here like this yes I haven't got it on my wrist we'll do some measurements like that in a second and it actually just goes into reset here you kind of sort flick on like that it's because it's taking gulps of energy and there's not enough output storage cap I need to put more capacitance on it I've just built up the charge on the output capacitance got a whole bunch of 100 Mike ceramic surface mount caps on the bottom of there and it'll briefly power this but it won't last for very long but you'll get the idea there we go well you saw it we even displayed a clock beauty so how much power can a tag like this generate well I've got measuring the output current here I'm just shorting the output with my micro amp range this has got a 1.5 ohm output resistance on this particular one and once again we're measuring the tag voltage like this so I'm actually going to put my hand on there and going up going up and turns out ah what do we got now 400 odd micro amps 40 millivolts let's call it that so you multiply those and it's not terrific it's only like you know 15 16 odd microwatts of that order but that's what you'd expect and it's enough to power you know micro powered modern micro power processes and stuff like that it's basic energy harvesting 101 but of course that power is just the output from the thermoelectric generator that doesn't include any power losses in the DC to DC converter at all and if we actually disconnect our tag from the circuit yeah we're going to get more we're going to get you know 700 odd micro amps something like that so we're talking about 50 odd micro watts but I know what you're thinking Dave what does it produce on your wrist okay I've got it on my wrist I've had it there for a bit and I've got it yeah not really tight down you don't wear your watch tight and of course it's on the top my arms aren't particularly hairy they're a little bit hairy but nothing out of the ordering and no I'm not going to wear my watch on the bottom where it has no hair that's ridiculous people who wear that silly anyway um and we get in about our 240 so you know 240 micro amps times 24 millivolts there well we're only looking at you know just over 5 micro watts it's bugger all but of course they're going to have a better thermoelectric generator than these these are you know leading research a group in thermoelectric generators I'm sure they got you know a pretty decent one anyway it's of that order all right so let's see if we can get some data on this baby when I exercise now I'd probably like a strap some multimeters in my backpack dialogue go for a bike ride something like that but unfortunately it's 36 degrees outside in Sydney today that's Celsius by the way um so yeah it wouldn't generate any power at all it'd just be at thermal equilibrium and it generate bugger-all so I'm in the lab here it's relatively cool I've got the aircon on so there is some sort of airflow going around the room so it's on full and oh just exercising lab' I'm generating about 16 micro watts at the moment once again it's it's not tightly coupled that want the heat sink to touch my wrists and all that sort of stuff so Oh see what I can do and see what I can generate it's gonna be fun and I've actually got to be careful cuz I've just had a knee reconstruction so I'll take it easy but anyway well here we go standard lab jumps and I'll just keep going still going but you can now actually see it ah starting to drop which is not unexpected I'm actually min/max are recording here so we'll be able to get the maximum value but uh not surprise us dropping at all and I'll explain that once I'm done and if you curious to see what's going on here with the Fleur I'll see if I can get it sorry about any reflections okay heat sink about 27 degrees something like that my hair are my arm not a huge amount you can see they my hand there's a lot more blood flow in my hand this is why you know you rest your hand on it before it's going to work fairly well but in this case so what starts happening as you exercise is the autonomic nervous system starts are shunting blood around the body to various parts and it'll actually suck the heat out of your extremities before it will actually pump it back in so longer you exercise you've got to exercise for quite some time before it'll start actually shunting blood through to your arms and actually using the surface area of your arms um to actually I get rid of your body heat that you've built up do in exercise and I'll actually link in her video by fellow blogger Thunderfoot and he's done an excellent video on this where he hops on an exercise bike and for like 20 minutes or something and you can watch the blood actually drain out of his arms and his arms actually get cold and then as he exercises for longer they'll actually want start warming up again it's really fascinating if you do short brief periods of like burst exercises then you're you know you're probably actually going to drain more heat out of your arm then it's going to heat up so that's going to cause a real problem and let's have a look at the meters here what have we got max thirty-eight record 38 that's like the best I get 380 micro amps 38 millivolts that's the best like he get to during that exercise granted I wasn't exercising for a half an hour an hour but you know a good 10 minutes and that's the best I could do so roughly we'll call that 15 micro watts using my just off the shelf ah tag here with my heat sink just flapping in the breeze but now I've got you know as I said I've got some my aircon air circulation in here a little bit on me maybe like a strap a fan on there and blow air across to simulate riding a bike or something like that you know but yeah it it's not terrific but granted they're going to have a better tag and better thermal design than my little MacGyver solution here so yes the product is going to work and yes they have got the right people on the team they're very likely to produce you know the final product I have you know quite a lot of confidence that they'll come through and produce it and all probably be a half reasonable product it's just pointless the thermoelectric generator me anyway if you want to discuss it down below catch you next time you

Channel: EEVblog

Views: 127,345

Rating: 4.8085561 out of 5

Keywords: eevblog, video, matrix powerwatch, thermal, thermal powered, teg, theroelectric generator, peltier device, pletier effect, heat, calorie calculation, calorie measurement

Id: y4OeOQtiW0w

Length: 29min 52sec (1792 seconds)

Published: Fri Nov 18 2016