 Any of you heard of that? No, I'm kidding. I want to talk about the tenth step, which is all about sun protection. Okay? So even if you don't know, all the nine steps is okay. It's pretty cool. Go and check out because skin carries health care. So UV index is actually recorded by every country, which is the strength of the sun and how harmful it is to our eyes, our skin. This is an example from the New Zealand Meteorological Department. This is an example from the Finland one, but they seem to have mapped it. But do you guys know that NEA locally also records it? And you can just Google NEA.gov.sg. And this was for today's one. I think today was fairly cloudy. So you can see that green means low, which is safe. And then 3 to 5 is moderate. This is basically UV index. And then you have 6 to 7 high, 8 to 10 very high, and above 11 is extreme. So a few months ago, I actually found a sensor that measures UV index. So basically it can also measure UVA and UVB, and then you combine it to measure UV index. And I found it on Adafruit, which is VML6075. This is a breakout board. The sensor is really, really tiny. It's like right in the middle here. And it has an I2C protocol, which is fairly easy to integrate. So you have the SCL and SDA. Because this is my first version of Prototype, I decided to use the breakout board itself. So if you guys want to play with the UV keychain, I can pass it around. But I'll also play with it and show you guys something. But also all the documentation, if you want to follow along, is at hutscape.com. So the idea is you just turn it on with a button, and you can either see it, the color schemes that you saw. So you see I have a little turn on button. Right now it's green because it is all safe here. There is no sun. So all you will see is green here. But you can also connect it to a Bluetooth low-energy chip on board. So let me show you the schematic. So for the hardware, I have used KiCAD. Any KiCAD users here, I think many of you, right? Wow, KiCAD is going better and better. I so like it. Especially KiCAD 5. If you guys have not tried it out, do it. So this is the board that I've used from the Adafruit. I have attached two switches to it. One to turn on and off the Bluetooth low-energy. And one to turn on and off the power itself. And basically on the other side, I have two other subcomponents. One is the UV sensor itself that I bought from the Adafruit. And I stuck a MOSFET to it so that I can programmatically turn it on and off just to save battery because I'm trying to go low power as possible. Because you can imagine you're going to hang this on your backpack and maybe go for an entire day hiking. So I want as low battery usage as possible. And finally, I also have the RGB LED. And for the RGB LED, I have obviously configured it to what the NEA website says. So it will be green, yellow, orange, red and purple accordingly. So you'll be able to see it. And if it's at the back or somewhere inaccessible, you can also connect to your handphone and see it. I'll show you. So hardware-wise, it's really, really simple. And for the footprint-wise, I have used the two breakout boards, the Adafruit NRF-52, which comes with the lipocharging circuit on board. So that made it really, really easy to do the lipocharging. I can also flash the firmware. So they did the USB support as well. And also they also have the I2C that I can connect with the sensor. So then I send it off to JLCPCB, and it came back. And I just soldered it. So after the hardware, so once again, the files are all available here. And this is where I bought it from. Let me talk a little bit about the software. At first, I thought I should only build the firmware itself. So for the firmware, it is Arduino compatible. This is what I used for my first prototype. So I used the Adafruit NRF-52, which is like a wrapper around the Sunday Mysteries library on NRF-52. And I used it for the firmware that I flashed here. So it does, like, okay, it detects whether the sensor is available and then it starts measuring it. If it detects the Bluetooth low energies available, then it will also start advertising so that with the handphone you can access it. Now I found two other client software. So I'll talk about the iOS first. No, actually let me talk about Bluetooth low energy. How many of you have played with Bluetooth low energy before? This is actually my first project using Bluetooth low energy. So I learned that Bluetooth low energy has something called GATS services. And if you look at GATS services, there's this entire battery and blood pressure and glucose monitoring. So the one that I actually didn't know that UV index was part of it. So under environmental sensing, which is the GATS service, you can actually have UV sensing. So once again, there's also GATS characteristic on each of the services. There is UV sensing as well. It's right at the bottom. There is like UV index. So basically in the firmware, what I did is I published the GATS service environmental sensing and the GATS characteristic UV index. I also published one more, which is the battery. Battery is also available. I published as the battery percentage so that I can measure how much battery is there and then charge it. The good thing about BLE is that it also publishes the format. So it tells you what unit to use and what it is for. So they are very, very well documented on Bluetooth.com. Just go to GATS services and it kind of tells you what is the intention, what is their intention of creating BLE for. It's to measure a lot of actually our health properties. Next up, I will show you the client software. So basically I did not build the BLE client. I just use the NRF Connect, which is the NRF. So let me quickly show you actually. Since this is already on, this is going to my handphone and this is the scanner. You can see, right? Where is, come on. I've turned off my, no, it is on. Okay, let me off it and try again. There's a lot of BLE. All of you have a lot of, at my home I don't have so many. So you see Farm and Hutscape. This is my device. I'm going to connect to it and I have published the environmental sensing and battery. Like I said, I've published to GATS services. So let me go to the battery because there's something interesting to see. So right now, the value you see is in hexadecimal actually, 34, which I do not know what it is in decimal. But if you do not want to build a client, you just want to quick and dirty one. You can use the NRF Connect. It was pretty useful. You can just see it. The next one that I want to show you in terms of software is Web BLE. I thought this was pretty interesting. Sign in each of the batteries. Sorry? In each of the batteries. Tilt. This one of mic. How much battery is left? Yes, in terms of percentage. On the device? On the device, no, sorry. Only when it totally goes off, then you see, there's no green light. So then you have to just press and charge. So let me show you. This is actually using Web BLE, which only works on Chrome. But once again, if you want to try it out, why not? So I'll show you. If you can go to hudskip.com slash palm Web dash BLE, you have it. So I will read the UV index. And wow, you guys have a lot of... I should have done a filter. Never mind. By the time I find mine. Okay. Anyway, so you see all the devices are coming up here, right? And if you connect to it, you should be able to see it. But I have a video. Let's see. So at home, I connected to palm at hudskip. And then it will start. And this time I went to the balcony to actually start reading. So it's green. And this one was at around 1 p.m. So just look at the UV index, Singapore. Okay. Sorry? This is high, yeah. I'll show you the NEA graph again. So this was for the UV index. Same as what we saw in the NRF Connect. And now I'll go to the battery level. This one, they will convert it to the decimals. So I think a couple of days ago, my battery level was 46%. So Web BLE tried out even though it's just Chrome. Yes, Kai. So once again, it was 8.9, right? So it was very high. Actually, NEA has a recommendation on what to do as well. Use sunscreen, use umbrella. Let me show you something. I think you guys, this was actually just today. This was just today. So this is like showing yellow. And I put my sunglasses. So what do you think will happen? I covered it with my sunglasses and it becomes green. So sunglasses does protect you from UV index. And I was testing to see whether my sunglasses actually works. Opaque. Oh yeah, absolutely. But yeah, I agree. But you can't wear opaque on your eyes. Can you, Kai? Maybe you can. So Web BLE is great. NRF is great. Let me talk about the bomb. The bomb cost was very high, $50 actually. I've open sourced all of them. That's because the biggest cost was the Adafruit NRF 52 feather. So in version 2, my main, main, main aim is to chuck out the module and use those, the ICs and the chip. Finally, for power. This little device has a tiny little lipo here. It is 380 milliamp hours. So how many days do you think it lasted? The answer was there. So if I turn on the BLE as well as the sensing every four seconds, how many days do you think it lasted? It's only 380 milliamp hour. I was really scared that the person won't be able to take it on hiking at the back. It lasted for five days. So I'm actually very, very impressed with the battery consumption, the power consumption of a Bluetooth low energy. Very, very impressed. And so it lasts for five days. I just left it on and it is completely drained. In order to help us measure how much is the current draw, Nordic, which is the NRF 52 chip, the BLE chip, actually has an online profiler. But I kind of found it a little bit difficult to use in the sense that, yeah, sure, it will tell you the average current draw, but by the time you have your eventual circuit, it's completely different. So it's good to take it as a gauge, but ultimately I think you have to measure it. And finally, I want to talk about the version 2. And of course, after all the talks, we can talk again. So the version 2, I don't want to use any modules as they are big and bulky, but I want to use the module that was inside the NRF 52, this tiny little thing itself. It costs a lot less. So I'm going to use that NRF 52. I also want to use just one switch, a dual pole, triple throw. I also want to use a smaller and brighter LED. You know, this LED looks very bright, but in the sun, it looks not bright at all. So I need even brighter LED. So I need to find that. And I'm also thinking of using a smaller rechargeable coin cell, maybe CR2450 if you guys have any experience with that, let me know. And I'm also thinking a lot about the mechanical stuff, like smaller, lighter, and that's why I want to have the one layer board so that the behind can still be used for battery housing. So, yeah, that is all. I don't think I have anything else. So that's the project. I'm going to maybe pass this around. Should I do it now or later? Yeah, we can hang out and now we can look at it later. I have the PCB boards as well if you want to look at it. Yeah, I think that's it. Thanks.