Career Episode 3: Ultrasonic Distance Measurement System Report

This report details a student's project on an ultrasonic-based distance measurement system. The project aimed to develop a compact and accurate device using ultrasonic waves for distance calculation. The report covers the project's background, objectives, and the student's role in designing the electronic components, including the transmitter, receiver, and power supply. The student applied electronics and instrumentation engineering skills, constructing a block diagram, collecting necessary components, testing individual devices, and integrating them onto a printed circuit board. The report highlights the use of CD4066 for the analog switch, the AT89C205 microcontroller, and μA741 and TL084 op-amps for signal amplification and comparison. The student addressed the initial challenges of using IR sensors by switching to ultrasonic technology for compatibility in various environments. The project's review discusses its completion within the deadline, user-friendliness, and limitations, such as range restrictions. The student contributed to hardware development, testing, and team support, completing the project successfully.

COMPETENCY
DEMONSTRATION REPORT
Career Episode 3
MOHD RAHMATH ULLAH HUSSAIN

CE 3.1 Project Information
Name of the project: Ultrasonic Based Distance Measurement System
Location of the project: [PLEASE FILL]
Project Duration: [PLEASE FILL]
Organization: [PLEASE FILL]
Role and Designation during the time: Team Member
CE 3.2 Project Background
CE 3.2.1 Characteristics of the project
The project has been based on the implementation of a system which would be able to
calculate the distance with the help of ultrasonic waves. The ultrasonic waves fall out of the
range of the human ear. Thus the waves can be used without any human hindrance. The system
which I had designed can be used in many situations. The device can be used a range meter as
well as proximity sensor for vehicles. The system consists of a transmitter and receiver which is
able to work with ultrasonic sound waves. The signal is transmitted, bounces back from the
object which is to be measured. The reflected sound is then collected by the receiver and the time
delay of the sound is then calculated to find the distance between the object and the origin of the
sound. The distance is measure with the help of pulse echo and the process of phase
measurement methods. The device uses a continuous flow of ultrasonic waves.

CE 3.2.2 Objectives developed for the project
The main objectives which had been set forward for the development of the project were
as follows:
 To make use of ultrasonic waves for the calculation of the distance
 To be able to make the device as small as possible
 To make the device as accurate as possible.
CE 3.2.3 My area of work
For the duration of the project I was responsible for the working on the electronic
component of the project. The electronic component of the project consists of the transmitter,
receiver and the power supply for the working of the project. I had also helped in the testing of
the device to know the limit of usage of the device which had been developed. At the end of the
project I had also helped in compilation of the documentation of the project which consisted of
the research and the process used for the development of the project module.

CE 3.2.4 Project Group
Figure 1: The hierarchy of the project
CE 3.2.5 My responsibilities throughout the project.
For the duration of the project I had helped in the working of the electronic component of
the project. I had helped in the connection and creation of the hardware model of the project. I
had also helped in the testing process for the completed device to understand the limits for the
use of the project device. I had then compiled the final documentation comprising of the research
conducted for the project and the process for the usage of the device.

CE 3.3 Distinctive Activity
CE 3.3.1 Comprehending the theory of the project
The project had been divided up in to two major divisions. The digital section and the
Analog section which were to work in correct coordination for the project to work. The digital
section consisted of the microcontrollers and the LCD screen which was to get power with the
help of a 5 V power supply. The Analog section consisted of three parts: the ultrasonic
transducers which worked along with CMOS Analog switch, the receiver consisting of a gain
amplifier, comparator and a voltage limiter. The two portion of the Analog section is to be
powered with the help of a 15 V power supply. I had worked on the Analog section of the
project. This helped me to understand the working of the ultrasonic waves for the measuring of
distances.
Figure 2: the block diagram of the project.

CE 3.3.2 Engineering knowledge and skills applied in the project
For the project I had used my Electronics and Instrumentation engineering skills. The
electronics skills helped me to device the projects hardware module. To complete the work
systematically I had first devised the working block diagram consisting of the different
components which needed to be attached to make the project complete. I had then collected the
devices which were to be used for the project. After the testing of the individual devices I
proceeded on to connect them to the bread board before making them into the final project. After
the testing had been done I had connected the parts onto a single printed circuit board. The next
steps were followed with care for the assessment of the project to be of the best quality and
certain tweaks which needed to be assessed to make the project of the best quality.
CE 3.3.3 Accomplishment and task performed
I had used CD4066 for the Analog switch in the transmitting unit of the device. As the
switch is only capable for the passage of positive voltage signals the negative signals are given a
DC shift of 0.5 V. I had then chosen a 20 pin 8051 based microcontroller AT89C205. this is to
be used for the counting of hex values for the LCD screen form ASCII values. I had then used
two μA741 opamp for the building of a gain amplifier as the sine waves cannot easily pass
through the Analog switch. For the amplification of the 40Hz signals received, I used a TL084
because of its high frequency gain characteristics. The comparator is used to compare the
received signal with a reference threshold signal level to measure the distance between the
device and the target. I had then used the time of flight method for the calculation of the distance.
The time required for the sound waves to be transmitted, get reflected form the target and then
get recorded by the receiver is recorded as the time of flight. Following the formula of “distance
= velocity X elapsed time”, I had replaced the velocity of the ultrasonic sound and the time

required for the flight into measuring the distance between the transmitter and the target. The
distance which is calculated by the formula gives the distance of the transmitter to the target and
then back to the receiver. Thus the distance is the double of the required value. I then reduced the
value to half the value was the distance between the device and the target.
Figure 3: the circuit diagram of the project.
CE 3.3.4 Identified issues and their solutions
3.3.4.1 Issues
The first draft for the project was to use IR sensors and LED for the measurement of the
distance. However when the device was not able to be used under water. Under the water the
light was getting refracted thus the calculations was being distorted.

3.3.4.2 Solutions
I wanted to make the device compatible in all kinds of environment. Thus when the IR
sensors was not the option to be used for the project I had conducted research on the topic of
measuring of distance. I then found the use of ultrasonic waves for the measurement of distance.
When this was implemented the project was able to be used for different environment.
CE 3.3.5 Plan to produce creative and innovative work
To make the project better suited for the use in real life situations I had increased the
power of the original project to use the device for a higher range. I had also used a temperature
compensation which helped the project to be used in a wide range of temperature. The project
which I have designed is compact in size and can be used as a parking assistance for commercial
and private vehicles. I was also able to improve the resolution for the measurement of the
distance with the use of phase shift method. The method was used along with the time of flight
method.
CE 3.3.6 Collaborative work
For the duration of the project I had received help from my team members and my project
supervisor. I had conducted most of the research for the project and helped my team members to
follow the timeline for the timely completion of the project. I had initiated many of the team
meetings for the discussion about the progress of the project and the issues which I was facing in
the project.

CE 3.4 Project Review
CE 3.4.1 Project Overview
The project was completed within the deadline was able to provide with the best quality
project. The use of the LCD screen with the microcontroller for the project helped to make the
project more user friendly than before. The project can be used for targets which have a
perpendicular. The project cannot be used for long range distance measurement due to the
unavailability of low power capacity.
CE 3.4.2 My contribution to work
I had helped my team members in the development of the hardware module for the
project. The hardware module was to comprise of the transmitter and the receiver module for the
project. I had also helped in conducting the test for the project and to know the usage limit for
the device. I had also provided support to my team members for the complete duration of the
project and thus was able to complete the project on time.