1. The document discusses theoretical and experimental methods for solving engineering problems. Experimental methods involve testing hypotheses by manipulating variables and measuring their effects. 2. The stages of an experimental method are outlined as objective and planning, methodology, data collection and analysis, discussion and publication of findings. 3. Maintaining a detailed logbook is important for recording experimental procedures, results, and analyses to allow for reproducibility and improvement of methods. Key elements of a logbook are outlined.

1. BMCU 1022
EXPERIMENTAL METHOD
CHAPTER 1
Introduction to Experimental Method

2. Importance of experiment in science and
engineering
Problem in engineering can be divided into 2 approaches:
1. Theoretical 2. Experimental
method explaining or
Works on method suggested will be
The theory
forecasting the result of an tested, measurement of
experiment based on quantity, deciding conclusion
analytical model and physical and will be used for building
concept regarding on some a good exercise in
phenomenon. conducting an experiment.
Knowledge needed: Knowledge needed:
• Basic concept • Measurement system
• Main principle • Apparatus system
• Analysis method • Hardware/ software
List down the criteria for each theoretical method and experimental method.

3. CLASSIFICATION OF EXPERIMENT

4. Criteria of theoretical method and experimental
method
Theoretical method Experimental method
Mathematical model analysis on
Analysis on real situation;
real world, where assumption is
assumption is not needed
needed
Give general results for all type
Give specific results
of problems
Relaxation in assumption lead to Measurement devices with high
complexity of mathematical accuracy are needed, if use
model apparatus is more complex
Not need to have many Complete and expensive
accommodations (trained person, laboratory accommodation is
pen, pencil ) needed
Time delay is needed for
Research can be started
equipment’s preparing and
immediately
testing

5. Experimental method
Experimental method involves manipulating one variable to determine if
changes in one variables cause changes in another variable.
Example
Objective: to determine the optimum strength of composite
materials with different nanoclay loading amount.
Change/affect
Variables 1. Composite materials’ strength, Mpa ed/result
: 2. Nanaclay amount, wt%
Varied, 1wt%, 2wt%,
etc
This method relies on controlled methods, random assignment and the
manipulation of variables to test a hypothesis.

6. Generally, the experiment will be conducted based on scientific
method, which is basically been used for all type of experiment.
Scientific
method
1. Change only one variable at one
time,
2. To test the method of
experiment
3. To test the reproducibility
Scientist To design an experiment that be
used to prove the theory
Experime
nt Engineer To find the differences
between result that been
gathered from theory and
experimental results

7. Generalized experimental method
Objective and preliminary planning of an exp.
Detail planning
Continuing on planning the methodology Modify the
exp.
Apparatus
Select instrumentation and/or
procedure
Collect a few data & conduct a preliminary analysis
Collect the bulk exp. data & analyze the results
Organize, discuss and publish the findings

8. Storing an experimental record
“Main attention for experiment must be given to record each
procedure in steps..”
Why we should
record?
• next analysis can be implemented without many
problems
• May be required to change a procedure,
improvement of procedure or change in setting of
equipment, etc.
• Reproducibility of an experiment
•…

9. Storing an experimental record
“Main attention for experiment must be given to record each
procedure in steps..”
How to record?
• electronic devices – computer(Ms Words, etc.)
• logbook/ laboratory journal

10. Logbook
Logbook has their role as:
• Tools for arrangement and references when writing a report
• Main record in patent law
• Preparing the record for overall experiment
• Information storage regarding on the procedure that is difficult
to find from journal articles
• As a note that explain the success or failure of an experiment

11. Logbook
Must be
binding;
piece of • Design concept
paper are
not allowed • first drawing or sketch
• first explanation (Generally),
(writing) must be
• first test or design included
• information regarding
on
first announcement to
outside world All the pages
must be
numbered

12. Logbook for engineering student
For engineering students, usually the experiments that been
conducted are for:
• to understand a concept in textbook
• to implement a standard test; e.g. hardness test, tensile test
• to check performance of a machine
• to find physical coefficient; e.g. gravitational acceleration,
elastic modulus for a metal, etc.
Recommended
1.Use a bound notebook for your log
2.Handwritten (exception: research is
primarily on the computer or use a handled
PDA to records)

13. Logbook for engineering student
• Date of experiment
Date
• Objective(s)
Objectives
• Apparatus that been prepared; take note
Apparatus regarding on how to use the apparatus,
preparation, etc.
• Create a table for the reading that been
Table/ Result taken, together with their UNITS
• Record all information needed to decide an
Analysis/Data overall experimental errors
• Make a necessary decision in order to evaluate
Discussion an effectiveness and level of success for an
exp. Plot a graph required together with their
• estimation error regarding on the experiment
Give a comment
Conclusion and discuss the result that been gathered
through crotical thinking

14. • Experimental design can be concluded as:
– Objective
– Planning
– Evaluation
– Uncertainty analysis
– Cost
– Calibration
– Data gathered
– Data reduction

15. Conclusion
1. Problem in engineering can be divided into 2
approaches:
a) Theoretical method 1. Concept
b) Experimental method 2. Knowledge
3. Criteria
2. Stages of experimental method
3. Storing an experimental method
Date
4. Logbook
Objectives
5. Logbook for engineering students
Apparatus
Conclusion
Results
Discussio
n Analysis/ Data