Design Brief - Sample Essay
Design a toothbrush holder, which will be used in a bathroom. Mr. Tooth, the toothbrush should be able to amuse children while they brush. A metronome timer must be used to time for three minutes and you should not be able to put back the toothbrush until then. The metronome timer will be shown in form of hands, clapping. There is also a clock on the mouth of the container to tell the time to the child and roughly how long more they have to brush for.
Furthermore the eyes would light up when the toothbrush is taken out the container. The logo, Mr. T, should alsobe on the product. It should last in daily use for a year and children would want to use it. A full explanation of the electronics must also be given. There must also be a full guideline of the parts used and the amount of money paid for each item. Problem Outline I aim to construct a child-appealing toothbrush in the hope that children in the future brush for the right amount of time. The timer in the toothbrush holder times for three minutes and so children cannot put back their toothbrush until that time has elapsed. As a loving dentist I hope that all children use this in a positive way and so making their teeth as white as snow.
Brainstorm I have decided to put my toothbrush holder onto a bathroom 555 cupboard. I will use a push to make switch so when the toothbrush is taken out the timer will start and a push to Light emitting diode break switch so when the toothbrush is put back in the circuit will break and the timer will stop. I can either have the toothbrush holder: have a clock on it’s lips, Nicad have a metronome timer or Battery have a chattering teeth timer. Light Mains Energy source Vacuum formed plastic Design Clock on lips.
Wood Metronome Box Toothbrush holder Timer buzzer Sound Chattering teeth Speaker Task Analysis: To make the timer for my toothbrush holder I will need to look at how to make timers. The components I will be using are shown in the brainstorm. I want to look at: What do they do? What are they made of? How big are they? Do they have any common features? Three things that I will look at when I do this are: Input Process Output E. g. timer e. g. a relay e. g. sound Specification: The product should cost under i?? 8 to build for each unit. 1000 units will be made.
The product must be waterproof.* The product must weigh less than 3kg. The smaller and lighter, the less the cost. The timer will need to be accurate within 3 minutes. The time-up warning will need to be in the form of a loud buzzer. The warning should go on for 30 seconds The electronics will need to be hidden inside a robust casing. The power source must last up to 30 hours. The casing and logo should be shown appealing to children so they want to use it. Bright colours should be used. * The power supply should be renewable. It should be 100mm deep.
It should be user friendly; users should be able to understand how to use it easily. The case should be safe to use. There must be no sharp edges or anything that may harm the children. Research: To build the circuit I will need to use the right components 555 timer: with the right amount of components used in each case. It is good to make a delay. You can do it with To do this I will research……… transistors. The 555 is an IC which is specially Made for the job. You trigger it, start the Action, and it gives a high output for a time. Light Emitting Diodes: This voltage is a pulse.
A pulse is a steady A light emitting diode is a semiconductor device that gives out light voltage that lasts for a fixed time. I can adjust when a small current flows through it. LEDs are used extensively as the pulse length of the 555 outputs, by electronic indicators. They are available in a range of sizes and shapes, connecting different components. Below is an and give out light of a variety of colours. The most common types are example of a 555-pulse generator. To trigger cylindrical and glow red, green, or yellow. This will be what I use. They circuit, connect pin 2 to the ground.
Output is are used in displays on devices such as bedside radios and car from pin 3. You can measure the length of the instruments. It is usually made from gallium arsenide phosphide, which pulse you have to look at the LED. emits light when a suitable current flows through it. The light output is caused by a release of energy that occurs as electrons pass from one side of the semiconductor junction to the other. The current flowing through an LED must be limited to avoid damaging the device. As it is a diode it will only let current pass through it in one direction. Motors:
Electric Motors and Generators, group of devices used to convert mechanical energy into electrical energy, or electrical energy into mechanical energy, by electromagnetic means. A machine that converts mechanical energy into electrical energy is called a generator, and a machine that converts electrical energy into mechanical energy is called a motor. Battery: Battery, device that converts energy stored in chemicals into energy in the form of electricity. It consists of two or more electric cells connected in series or parallel. A number of new types of batteries have been designed for use in electric vehicles.
Improved versions of conventional storage batteries have been developed for electric cars, but they still suffer the drawbacks of either short range, high expense, bulkiness, or environmental problems. Advanced batteries that show promise for use in electric vehicles include lithium-iron sulphide, zinc-chlorine, nickel metal hydride, and sodium-sulphur. Such batteries are also being developed by electricity supply companies to be used for “load levelling”, to compensate for momentary system load fluctuations. Such battery modules could be installed close to sites of variable demand.
They cause few environmental problems and occupy little space. Vacuum Forming: Most electronic products have plastic casings. These can be made by Vacuum forming high-density polystyrene sheet. The advantages of Vacuum forming are: a rigid shape that requires no fabrication. a repeatable shape a variety of details can be added on. complicated rounded shapes can be achieved by adding details. By using vacuum forming, I can easily shape my containers. The only problem with this is that stretching of plastic sheet can thin corners, meaning it is less safe. Nicads.
A modern NiCad cell is made with both plates being made of steel. The two plates are seperated By a thin layer of porous plastic. This separator is soaked in potassium hydroxide solution. All NiCads are fitted with a seal, which acts as a safety valve to release gas generated in the cell. The amount of cadmium used is very small so the cell is not as unfriendly to the environment as We believe. This is why I want to use them. NiCads thrive on heavy use. This is also good for me because the toothbrush holder will be used often. They would be able to last longer than batteries.