• 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...

Introduction

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.

Middle

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.

Conclusion

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)

    notice that the only numbers that come up were 2, 3 and 6. 7 never come up so I can say that my logic gate system works. Extra-lights It would be possible to have a light display on the dice so when the user gets a 6 a light sequence

  2. Electronics Project - Digital Metronome

    B6: The first time I tested my circuit, it worked. B7: There were no faults to fix as the circuit worked on the first try. Testing and Evaluation C1: To record data for the frequencies of the components in my circuit, I used a oscilloscope to determine the time period

  1. Design and Technology Project Design an Advertisement

    the L.E.D.'s "follow" each other Application - The above circuit could be used in my circuit to enable a series of LED's to "chase" each other possibly to highlight an advertisement. Explanation - The Monostable above acts as a timer, and the time is set via the potential difference of the variable resistor and the capacitor C1.

  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. Bicycle Alarm Project

    4. An auto-reset could be achieved in many different ways and is explained in the circuit description. 5. This is to be entered on a membrane numerical keypad and is described under the circuit description. 6. This is in the form of a tri-colour LED that is lit by pressing a key on the numerical keypad.

  2. An electronics firm wishes to introduce a range burglar alarms. This coursework contains the ...

    The sound sensor is very complex and may take too long to construct. Research - Sensing people walking along the hall As the task analysis shows there are many ways of sensing people coming through a doorway. I built them all using SYSTEM ALPHA to ensure that: They work I know how they work.

  1. Electronics coursework.

    to use the split circuit, which consists of two circuits interlinked by wires. I have chosen this because unlike the other designs it uses a smaller circuit board reduces space, as one of my specifications was to have a board that can fit into a modern car, which are rather compact.

  2. 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.

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