Richard,
I taught a level 3 biomechanics course at Exeter for years, but sadly had to
drop the practical component when we chose to allocate all third year
practical time to project work.
Spider silks and bivalve abductin are materials that do deform
measurably, respectively in tension and compression. I used to have
reasonable success replicating Mark Denny's old experiments hanging
weights from horizontally mounted lengths of spider silk , and Trueman's
incremental static loading experiment on eviscerated bivalve shells. For
the silk experiments (see Denny's chapter in Currey and Vincent 1980) the
best weights are pre-weighed bent entomological pins or bits of fusewire,
which hang directly on the threads. For the bivalve experiment (we used
scallops, mussels, cockles, anything we could get) I had a simple second
order lever made with a vertical bar welded on to it at right angles to apply
the pressure. The lever has to be movable on a rack and pinion to keep
the point of application constant. One can get good hysteresis loops, as
Trueman did. But these, and other materials experiments, always take
longer than one expects, so schedule plenty of time.
Only simple trig is needed, and the students generally coped OK, but over
the years I found that many knew nothing about resolving forces, and I had
a standard handout on triangles and parallellograms of force.
Basic experiments of this kind was were useful in several respects -
ludicrously low budget; the students could see the works and understand
what was going on; and the messages were simple but important. But it
was necessary to back them up with information about how one would go
about tackling the same problem nowadays: with dynamic loading, better
equipment and so on This could then lead to discussion of equipment
design, experimental design etc.
My main problem long-term problem was convincing expensive,
equipment-dependent colleagues that I was teaching serious science, at
a fiftieth of the cost of their own classes. My balloon, kapok and paper
aeroplane practicals are still muttered about...
Teaching biomechanics to relatively innumerate students always benefits
from nice handouts going slowly over ground one has covered verbally. I
can probably dig out some of mine if you would like to see them. We all
know the temptation to nod and say we understand a difficult concept
when we don't entirely, and students are understandably susceptible.
Best wishes,
Robin
>===== Original Message From Engineers and biologists mechanical
design list <[log in to unmask]> =====
>-----Original Message-----
>From: Richard Bonser [ <mailto:[log in to unmask]>
mailto:[log in to unmask]]
>Sent: 22 August 2003 09:00
>To: [log in to unmask]
>Subject: Student practical classes
>
>
>Dear All,
>
>I'm presently engaged in the Reading University New Lecturers
Certificate
>programme and part of this is a project to explore methods of teaching
>materials mechanics to undergraduate biologists. Primarily, I'm thinking
>about large-group teaching, rather than final-year projects and would like
>to find out how practical classes are conducted in various institutions.
I'm
>primarily interested in experiences gained while teaching biology
students,
>but would be interested to hear about experiences in other fields.
>
>I'd be very grateful if members of the list could supply me with
information
>under the following headings:
>
>1. Do you run practical classes in mechanics of biological materials?
>
>-If yes, what do these entail (materials, methods, what's measured)?
>
>Rubber bands and horse hair (tail); they make their own apparatus
using retort stands, clamps, spring balances, bulldog clips/paper clamps
and bits of wire. They carry out a simple tensile test on their specimens
and record the sample dimensions, force and extension. They calculate
stress and strain and determine the Young's modulus, breaking stress
and strain where possible.
>-If no, what factors make them difficult to run (e.g. cost, equipment, time,
>skills)?
>
>Equipment costs are cheap and it is extremely satisfying to deliver; the
students really enjoy it. It also brings together a whole range of skills
inlcuding teamwork.
>
>2. Do you find that students find the mathematical concepts hard to
grasp?
>Some of them find it tricky, but I give them some worksheets and an
introductory lecture \ workshop before the practical. I also provide them
with the answers and all of the working (some of them will need to go
through it in their own time) . It is not uncommon for some of the cohort to
have problems with scientific notation; I find that the key is to try and get
round them individually to make sure they can all do the calculations.
>
>3. What preparation do you give in lectures beforehand? Is there, for
>example, an introductory lecture to materials mechanics beforehand?
>
>
>Please feel free to contact me directly, if you prefer
>([log in to unmask]). In due course, I'll post a copy of the report
>on my website subject to consultation with those supplying info.
>
>Any assistance greatfully appreciated!
>
>Rgds,
>
>Richard
>
>
>
>Dr R.H.C. Bonser
>Lecturer in Biomimetics
>Centre for Biomimetics
>School of Construction Management and Engineering
>The University of Reading
>Engineering Building
>Whiteknights
>Reading, RG6 6AY
>UK
>
>Tel.: +44 (0)118 378 5219
>Fax.: +44 (0)118 931 3327
>Web: <http://www.reading.ac.uk/biomim>
http://www.reading.ac.uk/biomim
>
>I hope this is of use.
>
>All the best
>
>from
>Adrian
>
>Dr Adrian Goodman
>University of Lincoln
>Department of Biological Sciences
>Brayford
>Lincoln LN6 7TS
>Tel 01522 88 6802
>Home page: <http://www.lincoln.ac.uk/dbfs/staff/a-goodman.html>
http://www.lincoln.ac.uk/dbfs/staff/a-goodman.html
>
>Office in: Architecture Building, 1st floor, rm 1211
>
>OR
>Dr Adrian Goodman
>University of Lincoln
>Department of Biological Sciences
>Riseholme Park
>Riseholme
>Lincoln LN2 2LG
>UK
>Tel: 01522 895370
>Fax: 01522 545436
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