Arduino UV Index Meter - Working with Ultraviolet Light

today in the workshop we'll be working with ultraviolet light we'll learn how to safely generate UV light and we'll examine two sensors that we can use in our projects we'll even build a UV index meter that we can use to keep ourselves safe in the sunshine so grab your shades and sunscreen and welcome to the workshop [Music] hello and welcome to the workshop today we are going to be working with ultraviolet or UV light now we've already worked with light at the other end of the spectrum with infrared light we've worked with visible light using RGB LEDs to create light plus we've used video cameras before and so now we're working with the top end of the spectrum ultraviolet or light above the violet end of the spectrum now like infrared light we cannot see UV light but UV light is definitely useful for a number of applications it also has implications on human health now applications that UV can be used for include things like germicidal lamps these are used in the food service industry to prevent germs from gathering on meat and stuff like that counterfeit money and credit card detectors use UV light to expose little things that fluoresce under ultraviolet but are not visible under normal light water purification and air purification plants make use of UV light to kill bacteria in forensics it's used because things like human body fluids actually fluoresce under UV light it's used for curing adhesives and of course we've seen it used as lighting effects in the so called black lights that were very common back in the 1970s and 80s and so we've seen the uses for UV light and we're going to examine how we can create UV light we're gonna look at the things that actually fluoresce under UV light as well but on the opposite end of the scale we would like to detect UV light ultraviolet light actually has effect on human health now some of these effects are positive but a lot of them are negative including such things as sunburns and even skin cancer and in order to measure UV light we've come up with a scale an index called the UV index so I'm going to be explaining how the UV index works I'm going to show you how we can measure the UV index with an Arduino I'm gonna show you two different methods of doing it and then we're gonna finish off by building a UV index meter that you can actually use to go out and determine what the UV index is today and then take the proper precautions as far as things like sunscreen and staying in the shade go so there is a lot to cover today as always so let's start off by learning a bit about ultraviolet light ultraviolet light was discovered by Johann Wilhelm Ritter in 1801 the year after infrared light was discovered originally it was called oxidizing rays and interestingly enough infrared light was called heating rays the modern term for it is ultraviolet or UV light ultraviolet literally means above violet in the electromagnetic spectrum now here's a chart of the electromagnetic spectrum ranging from very long wavelengths or radio waves to ultra short wavelengths or gamma rays you'll notice that ultraviolet light sits between the visible light and x-ray light band on the spectrum now the UV spectrum is actually divided into multiple sections and there are many ways of dividing it one of the most common is to divide it into three sections UVA which is the section from 400 nanometers to 315 nanometers in wavelength this is often used with black lights and is not absorbed by the atmosphere UVB from 315 nanometers to 280 nanometers is the light commonly used in suntan boosts most UVB is absorbed by the atmosphere but some of it gets through UVC from 280 nanometers to 100 nanometers are often used for germicidal lights all UVC light from the Sun is blocked by the atmosphere here is a section of the spectrum that has visible an ultraviolet light notice where UVA UVB and UVC lie in the Specter exposure to UV see light is dangerous to human health moderate exposure to UVB light is actually good for you it produces vitamin D which is essential to human health and serotonin which makes you feel happy however excessive uva and UVB exposure can damage the dye optic nerve and the retina in your eyes excessive uva and UVB exposure can also damage your skin ranging from a bad sunburn to even skin cancer in order to measure UV light a UV index was created in the early 1990s here's an illustration of the UV index a low UV index is of little danger to most people simply wearing sunglasses will be sufficient the moderate UV index you should stay in the shade at noon wear sunglasses and apply a sunscreen of SPF 30 or higher a high UV index you should minimize your exposure between 10 a.m. and 4 p.m. again wearing sunglasses and sunscreen very high UV index you should also minimize your exposure even more again sunglasses and sunscreen are essential and with an extreme UV index you should avoid exposure to the Sun if possible and if you do go out sunglasses and sunscreen are imperative if you're building equipment that emits UV light you should put a UV radiation sticker on it such as this one to warn people about the dangers of ultraviolet light so now that we've learned a little bit about ultraviolet light let's create some now there are a number of methods that you can use to create UV light fluorescent lights are traditionally used for UV light you've seen these illuminating blacklight posters and are also used in sun tanning beds mercury lamps have been used to create UV you can create ultraviolet light with arc lamps if you need a very high intensity but these days the tendency has been to go toward LEDs for all of the advantages that LEDs have they have a very long lifespan and they consume very little current now UV LEDs are available in all sorts of different wavelengths you can get UVA UVB and UVC LEDs but by far the most common ones are the UVA LEDs and they're also the most inexpensive ones one other thing about the UVA LEDs is that although they admit ultraviolet light they also emit a little bit of light in the violet spectrum and that actually makes them easier to use because you can actually see the LED if you remember when we worked with infrared LEDs we really couldn't tell if the LED was on or off unless we measured the current draw and you'll have the same thing happen if you're using UVB and UVC LEDs but UVA ones you can actually see a little bit now whatever type of UV LED you're using or any type of UV light you need to take some precautions as I've mentioned ultraviolet light can actually have detrimental effects on human health do not stare directly into these light bulbs avoid excessive skin exposure and keep everyone else aware that you are using UV light so that they aren't exposed to lit inadvertedly as well if you're going to build a product using a UV LED make certain that you've got some sort of a warning label on it to alert people to the fact that this is emitting ultraviolet light now otherwise UV LEDs are basically LEDs they act like regular LEDs electrically you have to observe the correct polarity and you'll need a dropping resistor to limit the current going into them but otherwise treat them just like regular LEDs now I've got a couple of UV LEDs over here that I've wired up to a little Sodom's breadboard with a dropping resistor I'm just going to connect them up to this battery over here and as you can see they're sort of making a little violet bluish glow on them but they're also emitting ultraviolet lights and so now that we have a source of ultraviolet light I want to do a couple of experiments using ultraviolet light now the experiments I'd like to do with the UV light have to do with a property called fluorescence now fluorescence is a property that some chemicals exhibit and what it is is that when energy is applied to these chemicals and that energy can be electromagnetic or it can be UV light the chemicals themselves emit photons of light so they actually start to glow now this is different than something that just reflects light for example the image you're looking at right now me talking in the workshop I'm not giving off light neither is anything else in this workshop we are just reflecting the light that is coming at us from around the room and it's bouncing off of us and you're observing it in the camera however if something was fluorescent it's a bit different when the light would hit it it actually would cause it to emit photons so it'll actually glow now you've probably seen this before if you've seen a blacklight a blacklight poster or a room where they placed black lights and you'll notice certain things seem to glow quite a bit and that's because those things are fluorescent while a number of common household items are fluorescent as well so I decided that might be a bit of fun to turn the workshop into a little laboratory for a few moments and take a few household items and use the LEDs I just showed you and see if we can get them to fluoresce so let's go do that right now now for the first experiment I've made a little sign for you folks now as you can see it's a wonderful sign but it's got a bit of a problem it's on a piece of yellow paper and I used a yellow highlighter to make it so it's not the easiest thing in the world to read however under ultraviolet like things are a bit different so let me show you we'll bring it down over here and we'll dim our lights a bit here so we can see it and there you go chemicals inside the highlighter actually fluoresce here's something else that we can try now I've got two liquids over here I don't normally by the way allow liquids in the workshop but I'm going to make a little exception today so hopefully I won't spill it and as you can see I've got two liquids here and I'm going to put them down over here and we're gonna do an experiment on them now on the first one I'm shining my bulbs and it's pretty well what you would expect the glass is reflecting some of the violet or bluish light that we've got but nothing's really happening but when I go to my second liquid take a look at that the liquid itself is fluorescent now this is my mystery liquid over here this is tonic water a tonic water contains Queen 9 and Queen 9 a gain is something that will fluoresce and these are just two examples of things that you'll find around your home that fluoresce another thing that I noticed fluoresced is on one of my credit cards the MasterCard symbol I've just got two circles that you can see two colored circles you're familiar I'm sure with the MasterCard symbol but nothing written in them however under UV light there's an M and a C written in them on a Visa Card that someone else has I I noticed that there's a little bird symbol that doesn't appear when you see it in visible light but you can see it under ultraviolet light and of course as I've mentioned this is being used as a counterfeit money detector several different bills including American currency have little UV markings on them and they can be seen only under ultraviolet light and so this is the property of fluorescence and so this has been great we've seen that we can create ultraviolet light but what we really want to do is detect UV light and accurately measure it so that we can get a UV index so let's move on and do that now the first UV sensor that we're going to look at is an analog UV sensor now analog UV sensors are very simple devices they essentially output an analog voltage that is proportional to the amount of UV light that they are receiving now the sensor I'm using is called an SE NS 4/3 UV and I should mention this is not necessarily the most popular sensor there are a number of other sensors with different part numbers but they all work in basically the same way and most of them use the same sensor chip now you can also get devices from for example Adafruit and Sparkfun that have different part numbers but basically work the same way now these devices we as I said are very simple to use they basically have a power supply input and most of them can accept power supplies from three point three to five volts so they're compatible with most logic circuits and they have an analogue output and the analog output voltage will raise proportionally as the UV index goes up now I should mention this output voltage is very minut and I'll talk in a few moments about what to do with such a small voltage but otherwise it's a pretty easy device to use so let's take a look at how it's hooked up and then we'll do a little experiment with the sen s4 3 UV sensor the Sen s 4 3 UV is a typical analog ultraviolet light sensor it has a sensitivity in the range of 200 nanometers to 370 nanometers which covers most of the UVA and UVB bands its output voltage is proportional to the amount of UV it senses this device is available under several different part numbers but all of them function in an identical fashion the pin outs of the device are quite simple there's an analog output pin that outputs of course the analog voltage that's been sensed a VCC for the positive 5 volts and a ground connection the analog output voltage again is proportional to the amount of UV that is being measured as shown here so this is the setup I'm using to test my analog UV sensor the Sen s 4 3 UV this is the sensor itself down over here and I've got it wired up through my 5 volt power supply in my bench and to this analog multimeter now the reason I chose an analog meter instead of a digital one is I thought it might be easier to see trends in fact if you can look right now I'm getting a very slight voltage on this over here now this gives out a fairly minut analog voltage but we will see it respond when I add some UV lights so I've got my UV light source and I'm going to aim it at it and as you can see I am getting a reading there you go it's not a super high voltage but it is pretty well along the lines of what I figured now of course my UV light source over here is by far perfect it's not necessarily the exact wavelength that sunlight is that and it also is not calibrated in terms of intensity but as you can see the sensor is indeed reacting to UV light and it gives off a different voltage and proportion to the amount of UV that it receives what is what it is supposed to do so as you saw from the experiment the Sen s 4/3 UV is indeed responding to the ultraviolet light source now whether it's responding accurately or not I don't really know because obviously the UV light source I'm using is not in any method calibrated but it does seem to work however as you've noticed it gives out a very minut now we can indeed use this device with an Arduino or other microcontroller the Arduino has a 10 bit analog to digital converter which means there are a thousand and 24 different points of resolution that this can make now the problem with the Arduino a 2 D converter as it is is it has a range of 0 to 5 volts and a 5 volt Arduino 0 of 3.3 volts on a 3.3 volt one since our sensor is unlike to ever give an output of above 1 volt we're wasting a lot of resolution I mean think about it you've got 1,024 possible points of resolution on a 5 volt span if you're only using a maximum of 1 volt over there you've got 1/5 of that so maybe about 200 points of resolution you're wasting quite a bit well there is a solution to that and it's the Arduino analog reference function the analog reference function can change the reference of the analog voltage from 5 volts to a different voltage now there are two different ways of using the analog reference function one of them is to use one of the external pins on the Arduino you'll notice there's a pin called an a ref on an Arduino Uno for example if you feed a reference voltage less than 5 volts into that and use the analog reference command to point to that you can use that as your voltage reference so you could feed let's say a 1 or 1.5 volt voltage reference into it and use that instead and get much more of the range of the converter another way you can do this is with software and the analog reference command has a number of internal voltage reference points one of them happens to ideally be at 1 volt and it will work very well with this particular sensor now if you'd like some more details about that I'd urge you to take a look at the article that accompanies this video that you'll find on the drone bot workshop com website because I explain it in more detail now I'm not actually going to hook an Arduino up to this for a couple of reasons it is a very low voltage and once I do here in the workshop we really don't have a proper source of a calibrated UV light in fact the only way to really do that would be to take it outside and since I've got this hooked up to an Arduino I'd need to have some sort of a display etc it's not really worthwhile because I have found a better sensor to use one that is much easier to use with an Arduino and that's the sensor I want to take a look at right now the next sensor we're going to look at in the sensor that I'm going to use to build the UV index meter is called an SI one one four five now this is a very interesting and unique device it is actually meant specifically to give you a UV index reading and a very accurate one down to two decimal points but what's unique about it is it doesn't directly sense ultraviolet light amazingly enough it senses infrared and visible light from the Sun and it uses an algorithm to calculate the UV index and now while that might sound a bit strange it certainly does to me this device is very accurate and then the experiments I've done it matched what my weather service was giving me for the current UV index just about perfectly it is supposed to be a very accurate device now this device is an i2c device and so as such it's very easy to interface not only to an Arduino but to other microcontrollers and microcomputers such as for example a Raspberry Pi it's also available in a number of different packages now Adafruit makes this device in a couple of packages as well I'm not using theirs but you can certainly use theirs in fact we're going to use one of their libraries to drive the device one of the ones Adafruit makes is part of their floral line of wearables and I think a UV sensor for a wearable is an excellent thing you could build a garment that actually warns you that there's too much sunshine today we better get into the shade so this is a pretty fascinating device so let's take a look at the SI one one four five the SI one one four five is a UV index sensor with an i2c bus connection this unique device uses a combination of visible and infrared light to calculate the UV index the UV index reading is output directly so no conversion within software is required the device also outputs the level of visible and infrared light this sensor is actually available on a number of different module configurations with different pin outs however they all have this following four pin outs in common the VCC or power connection which is typically five volts a ground connection the SCL our clock connection for the i2c bus and the SDA or data connection for the i2c bus so now that we've seen a bit about the SI one one four five let's actually put it into action we're going to hook it up to an Arduino and write some code for it so let's go ahead and do that hooking in the SI one one four five up to an Arduino is quite simple we will of course need an Arduino I'm showing an Arduino Uno here and an SI one one four five sensor now your sensor may not look like the one i illustrate here but it should have the same connections begin by connecting the five volts in the arduino to the VCC on the SI one one four five note that yours may be labeled V in or VDD it's the same connection next connect the ground from the Arduino to the ground on the sensor the SDA line on the si one one four five is connected to either the dedicated SDA port on the Arduino or if your Arduino does not have one two analog input a four they are the same connection in a similar way the SCL connection goes to the arduino z' SC l output or two analog pin a five in order to work with the SI one one four five you're going to need to install a new library into your arduino ide so go up to sketch go to include library and go to manage libraries to open your library manager once the library manager is opened type SI one one four five into the filter box you could see the Adafruit si one one four five library now in my case I've already installed it but if you haven't installed it just click the more info button a little button will occur over here which allows you to install the library click the button and install the library once it is installed you can close your library manager now let's run an example sketch that comes with the library go into examples and go down to examples from custom libraries and look for the Adafruit si one one four five library you'll see one example si one one four five tests let's open that up now the example shows just how easy it is to work with the si one one four five we start off by including the wire library this is the standard arduino library for communicating on i to see and of course the si 1 1 4 5 is an i2c device naturally after that will include the library we just installed then we make an object we're going to call it UV and we go into our setup we setup our serial port and then we print out a two fruit si 1 1 4 5 test over here we initialize the device and then we print ok then we go into the loop first we simply print a separator and the si 1 1 4 5 can also look at visible and infrared light so we'll get their readings off of that right now the read visible reads the visible light and read IR reads the IR light so we're going to print those 2 values out there it is for our information of course what we really want to determine is the UV index and so we do that down over here we create a float called UV index and we do the read UV now it turns out that the output is actually multiplied by 100 so in order to get the real result we need to divide by 100 so this statement will divide the UV index by 100 and then we simply print out the UV index value to our serial monitor we add a one-second delay and repeat the loop over and over again so very simple let's take a quick look at how it works so here you can see I have my si 1 1 4 5 connected to an Arduino now unlike most of the experiments I've done before I elected not to use a separate solderless breadboard instead I used one of these prototyping shields which is simply a shield that sits on top of the Arduino it brings all of its pins out and also has a solderless breadboard on it the breadboard is actually optional you can also wire things directly to the proto board the reason I did this is I want to make this pretty well a self-contained unit because my intention is that once we get this working the way we want it to work I'm going to take it outdoors and actually measure some real sunlight so they didn't want separate breadboards and components all over the place however you can of course just use a regular solderless breadboard and the connections are naturally very simple there's only 4 connections from the device to the Arduino and two of them are power and ground and the other two being the other two I to see connections so at any rate I've got this sitting here right now it's running as you can see in my serial monitor I've basically got no UV which one would expect in a workshop a basement so I've got my UV LEDs now of course this isn't a calibrated light source I'm going to get readings all over the place but what I want to do is this make sure they am reading some UV so as you can see I'm getting some UV readings and the fours and the 3s and they fluctuate quite a bit because of course the way these LEDs are focused this takes a minut little movement change it but you can see that the sensor is indeed responding to UV light it's also giving off visible and infrared readings as well although in our final design we're going to ignore that and just concentrate on the UV index readings so now that we've seen this let's move on and construct something that's more practical and so now let's build our UV index meter now in order to do this we are going to use the SI one 145 and I'm going to add a liquid crystal display onto it now the display I'm using is also an i2c device because it makes the wiring so much simpler but you don't have to use an i2c display you can connect the display in the conventional fashion in the 4 wire mode and it will also work as well but I'm going to show you it with the i2c display so this way once I've got this hooked up we can actually take this and bring it outside and get some real readings so let's go and do that right now adding a liquid crystal display that a circuit is very simple since we're using an LCD with an i2c adapter simply connect the adapter to the same connections at the SI one one four five uses so the five bolts goes to the VCC or VDD the ground to the ground SDA to the SDA NSC l/2 SEL once you've done that we're ready to do our next experiment now here's the sketch we'll be using for the UV index meter we start off again by including the wire library for i2c and then we'll install the liquid crystal eye to see library this in course drives the liquid crystal display and we include the Adafruit library as well for the SI one one four five now first of all we are going to set up the LCD pinup so we define a number of integers over here for the LCD pin outs and the i2c address for the LCD now these pin outs are pretty specific to the i2c adapter for the LCD if you want more information about this I did an entire video an article about using LCD displays and you might want to cut that out also you might want to check into the i2c address of your particular LCD display if you don't use the same one that I do because it may be different so this is the value that I'm using for mine then we actually define an object that represents the LCD so this is the LCD object and we map out these pin outs over here these are actually the pin outs on the little eye to see adapter that connects to the LCD display then once again we're going to define an object for the Adafruit si1 1 4 5 when we call it UV now the setup is very simple we just start the LCD display as a 16 by 2 display and we initialize the sensor and the loop is also quite simple we start off by reading the UV level you'll notice this is exactly the same as the example sketch we just use the read UV and we divided by 100 to get the actual UV index and then we'll simply display this UV index on the LCD so we clear the LCD we set our cursor to the very top line in the very left hand corner we print out the words UV index with a space after them and then we print the UV index itself now on the bottom line we're going to set the cursor the bottom line over here and we're going to print out a little warning about the UV index so if the UV index is less than three then we're just going to print it's a low UV level UV index is between three and under six it's a medium level if it is between six and eight we're going to call it a high UV level and anything over eight is considered extreme UV so again we just print those results on the second line then we'll delay everything by a second and do it over and over again so quite simple let's take a look at it in action right now so here is our UV index meter with its LCD display and I'm going to just give it a bit of ultraviolet light and as you can see I'm getting a reading out of it very spasmodic reading but I would expect that because I'm certainly not using a calibrated light source and these LEDs are pretty focused but it certainly seems to work so it looks like our little UV index meter works quite well but before I bring it outside in the sunshine to give it a real test I want to add one more enhancement to it now this isn't absolutely necessary but I thought since this is going to be something that is measuring the ultraviolet index outdoors we might also want to know what the temperature is and what the humidity is and so that's an excellent application to add a temperature and humidity sensor now most of the time I use temperature and humidity sensors I use the dht22 and I've used it in a number of other projects and experiments that you've seen here in the workshop and it works quite well and it's fairly accurate but the one I'm going to use today is a bit different it's called an AM two three to zero and it looks identical to the dht22 and dht11 in fact the only difference I can see is that it's a different color it's black but in reality it is not the same because the four leaves on it are not the same connections that the dht22 uses this is another eye to see devices an i2c temperature and humidity sensor which has an accuracy comparable to the dht22 and so being I to see it's going to be very easy to add this the design we already have because we've got an i2c display and an i2c UV sensor it's just one more i2c device and this shows you by the way the versatility of the i2c bus so let's add our temperature and humidity sensor and finalize the design of our UV index meter adding the temperature and humidity sensor to our circuit is as easy as adding the LCD was because again this is an i2c device so we add the a.m. to 3 to 0 temperature and humidity sensor and connected as follows notice the pin out of the device from left to right the first connection is the VCC or 5 volt connection the next connection is the SDA connection the third connection is the ground connection and the final connection is the SCL connection now let's take a look at the modifications we need to make door sketch to add temperature and humidity to our display now we're going to be using the a.m. to three to zero temperature and humidity sensor which as I've explained is an i2c device so it makes the hookup very easy and as you'll see it also makes the code pretty simple now you're going to need to install two libraries actually in order to get this to work you may already have one of these libraries the Adafruit two three to zero library that we're going to be installing also requires the Adafruit unified sensor library many Adafruit sensors require this so you might already have this library installed if you've been following some of my previous tutorials you will have this but if not let's just go up into sketch include library and go into our library manager and once it opens filter everything by unified sensor now you're going to get quite a few listings go down near the bottom because these are alphabetical and look for the Adafruit unified sensor if it is installed wonderful if not go ahead and click the more info button and then click the install button now don't close the library manager yet you're going to need another one and that's the adafruit a.m. two three two zero library so filtered by a.m. to 3 to 0 again mines installed but if yours isn't hit the more info button and then hit the little button to install it once these two libraries have been installed you may close the library manager now the rest of this is pretty simple it starts off very much like the last sketch which you would expect it includes the wire library in the liquid crystal i2c library and the library for the SiO 1 1 4 5 then we add the unified sensor library and the a.m. - 3 - 0 libraries that we've just installed again we set up the LCD by defining its pin out and its eye to see address and we create an object for it same deal for the UV this is exactly the same as the last sketch we also define an object called a.m. - 3 - 0 now notice we don't actually invoke anything from the unified sensor library in the code it's the a.m. - 3 - 0 library itself that's dependent upon that and this setup is very simple we'll set up the LCD again and we'll set up the UV sensor now we initialize a temperature and humidity sensor and I'm going to print a little greeting on the LCD and the reason I do this is because for the first couple of seconds we don't actually have your reading so the display just looks a bit funny so I clear the display I set the cursor to the top left hand corner and I print UV temp & humid then I go to the next line set it to the corner and I print please wait and I'll wait for 2 seconds to let everything initialize in the background once that's done I'll go into the loop now reading the UV level is of course identical to before we take the UV read and we divide it by 100 and we display the UV index on the LCD so again this is very simple to what we did before will this go ahead and display the index on the top line now we also want to find out if it's low medium high or dangerous so we go through the same type of if statement that we went through in the last code and depending on the range we print out either low medium high or danger and I soared in the words because I want to print these all on the top line and I only have 16 character so I couldn't print the word moderate for example there weren't enough characters to do that and then we go to the bottom line and this is where we're going to display the temperature in the humidity so we set the cursor again to the corner and then we print out a T which is going to represent our temperature followed by a space and then we do a read temperature and then a C because we're reading the temperature in degrees Celsius and then after that we'll print out an H with a space and then we'll do a read humidity this is very very simple as you can see and then we will print out the humidity itself followed by a percentage sign because humidity is done in percentage then we're going to delay for 3 seconds and this lets all of our different sensors am 2 3 2 0 and the SI 1 1 4 5 have time to reset and the temperature and humidity probably won't change very much within 3 seconds and we start to loop over and over again to display it and so now that you've seen the code let's go and test our temperature and humidity added UV index meter so here is our new and improved UV index meter as you can see it says UV reading on the top and the temperature and humidity readings are on the bottom so once again let's just apply our UV light source and ensure that we're getting some readings on the top and we are indeed and so it appears to work of course the best demonstration for something like this would be to take it outside so let's go and take this outside now [Music] [Applause] [Music] so as you can see my UV index meter seems to work very well now one thing I should point out is some of you may have noticed the temperature readings I was getting it was indeed a hot day that I was out on it actually got up to about 31 degrees Celsius but I had some readings a lot higher than that and of course the reason is that my temperature and humidity sensor is being exposed to the direct sunlight because I'm trying to measure UV light so I needed to do that if you're gonna build an instrument like this and want to make it practical you'll actually have to find a way to shade the temperature sensor because temperature is always measured in the shade not in direct Sun so I just wanted to point it out that I don't live in the middle of the desert this is this Canada in the summer now we've built this UV meter and it's a pretty practical little unit we could put it in a little box and actually use it as a permanent device but the one thing about it is the display the LCD display is pretty good in the sunlight but it takes a bit more current than I'd like it to take if I was going to be running this thing the entire day so I've got a better display for you but you're gonna have to wait for one of the other videos to see that because I've got a really cool display that I want to demonstrate to you folks and I think it would be a perfect make for this UV index meter that we've just built so in order to find out about this wonderful display you're going to need to subscribe to the channel because that's the best way to know when I make new videos so if you haven't done that already just hit the little subscribe button below this video or you can hit that little robot icon in the bottom corner of the video and that will also let you subscribe to the channel while you're at it I would very much appreciate it if you would also subscribe to my newsletter now my newsletter isn't the big salesy thing where I'm trying to sell you stuff it's just a way that I keep in touch with people to let them know what I'm working on in the workshop and also send them survey so I can find out how I'm doing and what things you would like me to cover in future articles and videos now speaking of articles there is an article that accompanies this video as always you'll find the link to it below the video on the drone bot workshop komm website so until next time please take care of yourself please stay safe in the Sun and we'll see you again soon in the workshop good bye for now [Music] you

Channel: DroneBot Workshop

Views: 48,597

Rating: 4.953125 out of 5

Keywords: Ultraviolet light, UV Index Meter, UV Index, Sunburn, Arduino, Arduino Project, SI1145, SI1145 Arduino, UV Light

Id: dBljvUBZqI8

Length: 46min 43sec (2803 seconds)

Published: Wed Sep 05 2018