Download
1 / 32
360 likes | 596 Vues
Lab Teaching. Organization. Role of Laboratory Teaching How various persons see it. Aims of Laboratory Teaching Pedagogical levels. Major Problems What can be done. A Typical Laboratory Exercise. Design of one course Experimental Aerodynamics. 2. Standard Solution offered :.
E N D
Organization Role of Laboratory Teaching How various persons see it Aims of Laboratory Teaching Pedagogical levels Major Problems What can be done A Typical Laboratory Exercise Design of one course Experimental Aerodynamics 2
Standard Solution offered: Increase Practicals - which means Lab classes Common Complaint Bookish - not practical enough
How they view labs Teachers Students Administrators Education planners
SpecificAims • FAMILIARISATION with • standard equipment • measuring technique • ILLUSTRATION of • physical phenomenon • concepts taught in lectures • TEACHING of • attitude to experimental work
Specific Aims • TRAINING in • observation • deduction from observations • critical awareness • keeping lab notebook • writing reports • experimental design • acquiring specific information • PROVIDING • closer contact with faculty • stimulation for independent thinking • feel for R&D labs
Classification These objectives can be classified in three categories: • Teaching experimental methods (EM) • Supplementing lectures (SL) • Incidental aims (I)
Bloom’s Taxonomy of Objectivesin the Cognitive Domain • Knowledge • Comprehension • Application • Analysis • Synthesis • Evaluation
Cognitive Levels • FAMILIARISATION with • standard equipment • measuring technique 1 1 1 1 - EM EM SL SL EM • ILLUSTRATION of • physical phenomenon • concepts taught in lectures • TEACHING of • attitude to experimental work
CognitiveLevels • TRAINING in • observation • deduction from observations • critical awareness • keeping lab notebook • writing reports • experimental design • acquiring specific information EM EM EM EM EM EM EM I I I 1 2 ~ 3 3 ~ 4 1 - 4 1 - ? - • PROVIDING • closer contact with faculty • stimulation for independent thinking • feel for R&D labs
Exhibit 1 Strain gauges Time taken? What are they learning?
What are we trying to teach? • Follow recipe • Results in reduction exercise – a numerical problem with realistic data
Abdulwahed-Nagy Constructivist Laboratory Model Based on Kolb’s Experiential Learning Cycle
The Issue Why does an engineer undertake an experimental investigation? • For obtaining design data • To verify that the designed object meets the performance objectives
Major Problems with current design of labs Vital aspects such as selecting or devising the apparatus, what measurements to be taken, what variables need to be controlled are not addressed to by the students. How the tests have to be conducted and how the accuracy has to be estimated is also not in the control of students. Students are not given the opportunity to think for themselves.
What is needed? • Deciding what needs to be measured • deciding what sensors and instruments to use • Configuration of sensors and instruments
Extended Discretionary Laboratory Teaching (EDLT) 1. An objective or a task – usually given in one sentence, sometimes as a question. 2. A very brief guide in a two or three sentences as to the major direction to take, 3. Resources available – which may include definitions, special techniques, materials, references, parameters, or other information needed to fulfil the objective or complete the task.
A course in Experimental Aerodynamics Two 1-hr lectures + One 3-hr lab a week Lecture contents: Principles of experimental design Hypothesis formulation & testing Error estimation Problems of measurements and validation Similitude + subject-specific techniques
Lab Programme About 10 experiments posed with a minimum of instructions Students are expected to plan their experiments about the given equipment and chose the necessary uniquity parameters making sure that the modelling range is as required for the phenomenon.
Revised Experiment of Exhibit 1 • Convert the given ring of metal into a load cell and calibrate it.
Incidental Aims • Report writing • Oral presentation • Use of presentation software
Incidental Aims In addition, each student is expected to submit TWO experiments written up as formal reports, as if they were communications to a technical journal. Format specified for the technical notes in the AIAA Journal is to be followed. This would count for 20 points.
Design of Lab Courses • Lab experiment should not be laid out completely. There must be decisions that a student has to take. • The purpose of an experiment in a lab course is to teach a student the experimental method. For this purpose, give minimum of directions. The student should gain control of the decisions that are made while conducting experiment. • The student should choose the uniquity parameters of the experiment.
Design of Lab Courses • Experiments should not be just demonstration, or verify the law type. Must involve collecting data for design, or testing a prototype to verify if it meets the specs, or investigating a new situation. • Error analysis, up to and including calculation of error bars should be essential requirement for each experiment. • Each experiment should be so designed that it takes up the full assigned time.
Design of Lab Courses • Student should be taught how to keep a lab record book. • We should not require students to write up reports on each experiment. For most experiments it should be the lab record book that should suffice. • We can and should teach student technical communications in lab courses. This may be done by asking students to write up some experiments (one or two) as a Technical Note to a standard Journal using the format specified by that Journal.
