• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Specifications for the Ultra Sonic Proximity Detector

Extracts from this document...


Electronics AS coursework Aim To design and build a proximity detector for the rear of a car that is used when it is parking. The sensor's main objective is to decrease stress for the driver and make the task of parking easier and quicker. The sensor will use ultra sound to detect close objects. Initially the project will produce a simple mechanism to portray the idea, which then can be developed. For example the feedback to the driver could just be a buzzer that comes on when the car is too close. Research I chose to use ultra sound in my sensor, because I have had no experience with the components so it would be a good research topic and hopefully prove to be interesting. The transmitter sends out the high frequency pulses, which reflect off of objects and are detected by a receiver. The longer the time between the emission and detection the more the amplitude of the wave decreases. Also the waves are transmitted in a 20? arc, I was able to find these facts from Rapid electronics company whom sent the ultra sound part I requested. ...read more.


The receiver leads into the op-amp circuit. From a decided distance of 40 cm the amplitude received read 1.8 mV, I needed the voltage to be amplified so it could switch the trigger. The switching voltage of the Schmitt trigger is of the order of about 2 V. This showed me that I needed a gain of about a 1000, which is a lot so problems would occur. The theory proved successful and the gain was achieved; however the op-amp had a lot of regular spikes on it, exceeding the required voltage, also some clipping occurred. If this persisted then it would fault the Schmitt trigger and so the circuit would not work. To stop this I needed the source of the problem, so firstly I tried a smaller gain, which made the spikes smaller, so did not really help. I tried changing the resistor input to the op-amp; this did alter the spikes and clipping but not to a significant enough effect. I eventually found that by using two power supplies, one for the 555 timer and transmitter and the other used with the receiver and the rest of the circuit. ...read more.


Assessing The whole circuit I am pleased to say works well and reliably, however the ultra sound has to be placed in the exactly the right direction, because the waves are easily reflected by any surface. This means the unit will have to be mounted in a suitable position so that the waves will be reflected off the bumper line of vehicles. Limitations and modifications Most of the development took place in the construction and I have detailed these in the sub-systems report. In addition to these I would like to mention some ideas that would improve the sensor. The first is that the sensor only gives one piece of information feedback, if I were to improve this then the more information would make the system safer and more reliable. For example addition latches could be added to trigger the D-type at different distances from the object. This would allow the driver to be more alert when parking. The Final modification I would consider would be to allow the driver more control over the sensor by adding a specific on/off switch and also a timer for the alarm after it is triggered so it does not become annoying for the driver and passengers. Summative Evaluation Proximity detector James Ashley-Smith 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Systems and Control section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Systems and Control essays

  1. Marked by a teacher

    Electronic Dice Project.

    3 star(s)

    LED that will give the look of a real dice I will use this instead of the 7 segment display, this diagram sows how the LED's should be set up: Here is how the light will show up the different numbers: Final Testing When all put together my circuit and

  2. Elecrtonics - Audio Amplifier

    This sub system is working properly. Subsystem 2 - Volume Control The circuit to control the volume is shown below. The variable resistor is the control, when its resistance is set to zero the output signal should be the same power as the input signal and the amplifier will be operating at full volume.

  1. Wailing Alarm Siren

    install A high quality internal PIR sensor using the latest technology to provide superior immunity to false alarms and to white light. The automatic pulse count evaluates the size of the mass detected and reacts accordingly reducing false activations. A simple adjustment allows the same lens to act as the standard wide lens or become a curtain or pet lens.

  2. Bicycle Alarm Project

    This prevents unauthorised persons using it as pressing the wrong number will activate the alarm. The correct number can be set by the operator. Circuit description Keypad and PIN decoder (IC1) There are 2 main types of keypad output that can be used.

  1. Getting On Line Without a Computer or Internet Access at Home

    Parent Involvement in Education: www.ncpie.org National Council of La Raza: http://www.nclr.org/ National Family Caregivers Association: http://www.nfcacares.org/ Parents Anonymous (parent support to avoid child abuse): www.parentsanonymous.org Parent to Parent USA: http://www.p2pusa.org/ Prevent Child Abuse: www.pca.org New Jersey Libraries Offering Free Internet Access to Patrons (Alphabetical Listing)

  2. Design and Technology Project Design an Advertisement

    and lights a new one. Now the rate at which the 555 pulses is set up its resistors. Now depending on the speed of 555, the speed in which the L.E.D.'s light is determined. The result with many L.E.D.'s attached is a chaser circuit i.e.

  1. Solar Power

    The turbines burn only 40 percent of the natural gas they would if they were fueled by natural gas alone, and better heat recovery technology would lower that figure to 30 percent (Energy advocate). Electricity from photovoltaic farms in the Southwest would be sent over high-voltage DC transmission lines to

  2. Aim: 'Build a sensor circuit to test the proximity of an object using a ...

    connected to a bulb with a clamp holding the bulb in place for the simple circuit.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work