D&T: Electronics and Control Systems Unit A511: Introduction to designing and making Name: George Wilson Candidate number: Centre Number: 16527

creativity I chose this because several people die every year for something that could be so easily stopped. Another reason is that I couldn't find any products that really fit what I would expect from and alarm for this purpose in a cheap price range.

User needs

conclusion My conclusion is that there are three main types of people this happens to. There are two main places this can happen. Knowing that there is three main people that this happens to will help me a lot to design my product as I want to build my devise around there needs. Knowing that there is two main places will also help me but not as much I will try to fit my devise to suit these places but this is as important because it could be needed anywhere.

Reasons I chose this idea because many people get severely ill and some even die of such a small and easy to fix thing. I believe there is a good gap in the market for a devise like this as long as I keep it: Cheap Simple Well working Trust worthy

Article -3/abstract Four risk factors for overheating were sought in the histories of 34 cot- death victims in Oxford and Scarborough. 19 babies were unusually hot or sweating when found dead; 14 died in an unusually warm environment; 17 had evidence of a terminal infective illness; and 24 were excessively clothed or overwrapped. 3 babies had all four risk factors, 8 had three, 17 had two, and 4 had one risk factor. Only 2 had no risk factor; both had had very low birth weights. In 6 of 15 babies (40%) whose rectal temperature was recorded after death the temperature was above 37°C, the highest being 42°C. If parents could be educated to anticipate the dangerous situations preceding febrile apnoea, many cot deaths could probably be avoided. This is an article what could have been changed using my devise.

Questionnaire Have you ever fallen asleep and woken up really hot or cold? Has any one you know ever fallen asleep and been unable to change the heating and become seriously ill or worse? If so what age was the person? under 10 A B C 50+ D

Questionnaire Were was it? house A Oap home B hospital C other D where they/you alone? How much would you pay for a device that alarms you when the heating changes above or below a pre set level?

Questionnaire £0-10 A £11-20 B £21-30 C £31-40 D £ 41+ E Do you think this product is a good idea?

Results Q1 : Q3: Q5: 1 C 8 Yes 1 A 3 yes 2 D 2 no 2 D 1 E Q2: Q4: Q6: Q7: 3 yes 2 A 2 A 9 yes 7 no 1 D 4 B 1 no

Feature describedReason for feature The purpose of my product is to alarm and wake up an elderly person when it gets to hot or cold. This is to save lives. The proposed product needs to measure heat levels and notice when its to hot or to cold. So it can set off the outputs. The proposed product needs to sense heat levels and when it gets to hot or cold for an elderly person. So it can set off the outputs. The output of my product will be a siren and a red, green and blue LEDThis is so you can wake the user and also show them the temperature problem. My power supply ill be a battery so it can have portability.The user might want to take its somewhere where there is no power supply My circuit ill run off 9 volts.This is the main voltage and will be good for my circuit. My product will have an off and on switch.This is because they might not always want it on or they want to reset it. My circuit ill have a power on indicator.The power indicator will be a LED to show the product is working. My circuit will be deigned on circuit wizard because it is easy and simple. This is because it is easy and it links to the Denford for an easy and quick making. My circuit will be manufactured starting with the Denford circuit board make to put the tracks on the board then I ill solider my components on. I will use this method because the Denford links from the circuit designer. I will ensure that my product works and is very reliable by putting it through a series of tests. I will do this because I want all the users to fully trust my product and be able to sleep without worrying.

Other products £54.99 Old people in house Alarms temperature movement Measures temp and alarms £39.50 All user, portable Shows and alarms temperat ure £ Baby's and all animals Changes the temperatur e This has got a thermostat and a alarm. This has got a thermostat and a alarm Circuit board manufacture

£54.99 XL wireless temperature alarm system is a very easy to use & install, cost effective system used to monitor high and low temperatures inside and out. £39.50 Select ºC or ºF, Min and Max Temperature Alarm,Relative Humidity Alarm Stands or Wall Mounts, CE Certified Temperature Range -58°F to 158°F, Humidity Range 20% to 99% RH £ Simple Wireless Temperature Alert System Dakota Driveway Alarm systems used to easily monitor Low & High temperatures. Powered by a simple 9 volt battery, and with a range of 900 meters

Conclusion So far my research has shown me that there is defiantly a gap in the market for my product. Not having a product like my one causes hundreds of deaths and various illnesses each year. My results also show that the other products on the market are either too expensive or not reliable enough I am trying to get in the middle of this gap. To do this I am going to the use the program circuit wizard to put my circuit into evaluation.

Compare two products Name and picture of product 1 Aico EI 144 Heat Detector Battery/dp/B003NW37H0/ref=sr_1_3?ie=UTF8&qi d= &sr=8-3 Name and picture of product 2 Philips AVENT SCD525/00 DECT Eco Baby Monitor Monitor- Temperature/dp/B003P9WSXU/ref=sr_1_17?ie=UTF8 &qid= &sr=8-17 Function Detects heat levels.This products senses heat levels and also sounds a alarm and plays lullabies to clam your baby User need fulfilled This product fulfils user needs but could be easy to use with batteries and more reliable. This product defiantly fulfils a users need if they had a baby but if they were a old person needing this it would be a bit of a waist of money. Materials used in construction This product uses the basics a circuit board and components. Also injection moulded plastic. This product has 2 circuit boards in it and uses strong moulded plastic. Durability of product The durability of this product looks pretty poor because the plastic doesn't look very strong. This product looks pretty durable and strong. Sustainabilit y (6Rs) This products isn’t recyclable but you could reuse it or sell the components. This product is recyclable reusable and you could make it into something else. Life cycle Energy use

My products circuit My product will have: The input of a heat sensor and cold sensor, i will use a or gate to add these two inputs together. My process will be a Darlington pair because its stronger than a resistor and I will need the extra power. My output will be a buzzer also 3 LEDs 1 blue one green and one red standing for too hot too cold and just right. My power supply will be batteries so that my product is portable and more safe. Also it is harder for my to add a mains adaptor into my circuit. I will design my product in circuit wizard.

4 circuits

Chosen one I chose this circuit because it is closest to what I want although this is exactly what my circuit is going to be like. In my circuit I will not use a 55 timer chip This is because I don't need my circuit to be on And off like a timer.

Design when I first created my product it was three circuits one for each heat level. I created this and two circuits did not work. One of my circuits was overlapped on the joints so I fixed that problem. See picture 1 My second circuit did not have a high enough voltage which I forgot to set when I made it. The other problem with it was I needed to change the settings on the heat sensors to fit the led colour. See picture 1

After I had fixed these problems I was trying to improve my circuit knowing that a big weakness was that it was 3 separate circuits. I attempted making it all into one circuit. I put my circuits into one so it will be easier to make and a lot cheaper. See picture 2 After this I made my circuit into a PCB and changed the tracks so they were thicker and easier to solder, I also changed the pad size so I was less likely to burn them off when soldering. After I had done this my circuit did not work so I tried to auto route it so it has enough space. See picture 3 I changed the circuit around a bit and got it to work. See picture 4

1)2) 3) 4) Pictures

Test plan What should happenDoes it happen (yes/no) When you turn the devise on one led must glow, if it is red or blue a buzzer must also sound. Yes If the circuit has a blue or red led glowing and the buzzer is sounding, depending on the colour of led when you heat or cool the room to a good temp it should go to a green led. Yes If the circuit is showing a green led glowing if you heat or cool the room the colour should change and a buzzer should sound. Yes When you turn the switch off the circuit should shut down(meaning any led turn off and the buzzer stops). Yes The buzzer and Led say on until you change the temp or shut down the circuit using the switch. Yes When the green led is glowing the buzzer is not sounding. Yes Green led showing is a safe temperature.Yes

Description of ProcessTools/Materials requiredTips for success Design PCB and create mask Circuit wizard Cut board to size Expose Mask and photoPCB to UV Develop exposed PCB Etch PCB Drill holes in solder pads drill Add resistors Resistors,solder and a soldering iron Be careful not to put to much solder on. Add capacitors Capacitors,solder and a soldering iron Be carful not to burn the pads on your solder board. Add transistors/thyristors Transistors/thryristors,solder and a soldering iron Be careful not to over heat the components Add Chip socket Chip socketThe pads are very close on chip sockets so make sure the solder does not link the pads Add off board components off board components,solder and a soldering iron Make sure you do not burn yourself Add chip to socket ChipBe careful not to bend the chips legs.

Making (slide 16 to 18 - approx) Manufacture of the circuit Include photographs to show the stages of the making of your circuit Annotate each picture to show what is happening. Highlight any problems that were encountered and what you did to solve the problem or anything that you changed as the circuit was constructed (i.e. what is different to what you planned. This is an important part of the mark scheme. In addition: – You must include a clear photo of the whole circuit including the off board components and the connecting wires. – You must include a clear photo of the top side of the PCB showing the components. – You must include a clear photo of the underside of the PCB showing the soldered joints. To ensure the marks for problem solving are gained it might be best if the changes mad and the problems encountered are summarised at the end of this section.

In this picture I am tinning the wire. This means creating a layer of solder around the wire which keeps it all together In this photo I am soldering in my resistors making sure I have the correct values. I checked this by looking at the colours on the resistor In this picture I am shrink wrapping. This is when you get a little plastic tube and melt It onto your wire. Here I am showing you how I keep my components in place while I solder. I bend the legs over, in some cases the legs or components are very strong and you cannot bend them (chip socket). In this case you put a little bit of tape over the top to keep it in place This is a final picture of my finished circuit. This is a final picture of my circuit solder side up. This picture shows me soldering.

Problems and errors

Tools I used Soldering ironBubble etch tankPcb Heater for shrink wrapping Wire cuttersWire strippers

Evaluation (slide 19) Testing your circuit Show a step by step plan that can be used to test your finished circuit. Write it as if it were for a person who does not know how it is supposed to work. Tick of each step to show that the circuit works. Evaluation Describe what went well and what did not go so well in the manufacture of your circuit – Consider the development of the circuit and the development of the PCB – Consider the actual building of the circuit Could it have been made differently? – alternatives? Could it have been made better? – how? Compare what you did to the steps of your plan See table on next slide as a suggestion.

Evaluation (slide 20) Evaluation (continued) Description of ProcessWhat went wellProblems encountered/changes made Action taken to deal with problem Design PCB and create mask Cut board to size Expose Mask and photoPCB to UV Develop exposed PCB Etch PCB Drill holes in solder pads Add resistors Add capacitors Add transistors/thyristors Add Chip socket Add off board components Add chip to socket Copy the planning table and edit as required. Comments only need to be brief.

Evaluation (slide 21) Improvements In addition to describing how the circuit could have been manufactured better; Describe how the circuit could be improved to function better to solve the problem more effectively. – Different inputs – More inputs – Different control of the outputs – Different outputs