Is this Educational ?

I found this short, and very well presented, series of videos on Youtube last night:

**LINK** https://youtu.be/sx5VR6oJWaY

It documents the assembly of a useful ‘Syringe Pump’ … similar in concept to the ones I mentioned recently on the Chain Oiler thread.

What concerns me [a little] is that although existing in an Educational environment, it is noticeably short of teaching anything other than rudimentary manual skills.

Obviously the education will come with students’ use of the device … but should they also be taught a little more about the design and manufacturing process ?

… is this a missed opportunity, or just the reality of modern life ?

… I honestly don’t know

If it catches your imagination, please discuss.

MichaelG.

It's the fault of the 'get a taste of everything curriculum'

I may be out of date but a few years ago I looked at what 'metalwork' classes at school had turned into and it seemed to be "resilient materials GCSE". An example exam paper seemed to be mostly "what might it be made of" and "how would it be made?" as this could be taught as production concepts without having to risk actually touching bits of metal.

Resistant Materials still requires a final project for the majority of the marks, the syllabus states that:

"The Non-exam assessment will contribute towards 50% of the students overall mark. The NEA project in its entirety should take between 30-35 hours to complete and consist of a working prototype and a concise portfolio of approximately 20 pages of A3 paper, equivalent A4 paper or the digital equivalent."

Which hasn't changed since I was at school (some significant time ago).

I seem to remember using it as an excuse to build a new seat for one of my whitewater racing canoes from composites (the DT teacher was an avid canoeist too), whilst my mate who wanted to play with all the big tools made a safe out of 20mm thick steel (and also failed to recognise how taking it home on the bus at the end of the school term would in fact be rather difficult).

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I have a friend who has now worked their way up to being the Head of DT at a large secondary schools and their take is that In practice DT teaching is now a pot luck.

Some students will have enthusiastic and knowledgeable teachers in well funded workshops, whilst others will be taught every DT subject by the same two or three stressed and burned out teachers in dilapidated facilities with little budget for materials.

There's an obvious correlation between the school's overall funding and DT funding; but their experience is that it's the influenced even more by whether people who recognise the importance of design and engineering are present within the senior leadership of the school, the governors, and the leadership of any academy group they're part of. Many well funded schools don't do a good job of it because leadership prioritises traditional academic subjects like Maths and History over more applied ones.

Edited By Jelly on 02/10/2022 22:12:38

I think this is actually about making flow chemistry more accessible to students and researchers at universities in less economically developed countries (or cash strapped PhD students in the western world wanting to make their research budget go further, and with access to a 3D printer in the departmental workshop).

In that context the making is entirely irrelevant to the learning that the people publishing this wanted to inspire, and more about increasing engagement with the concepts of flow chemistry (i.e. carrying out chemical reactions as a continuous process at the lab scale where that is still novel).

I have some sympathy with your analysis, Jelly … it just struck me as odd that the build process seemed more appropriate to a disinterested assembly worker than to a student who would be using the product [and perhaps have enough wit to notice its shortcomings]

MichaelG.

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P.S. ___ this is probably a better page than Youtube to navigate from:

https://chem.uncg.edu/croatt/flow-chemistry/

Ref. https://researchmagazine.uncg.edu/wp-content/uploads/PDFs/2019/spreads/Doctored-Molecules-spread-format.pdf

Edited By Michael Gilligan on 02/10/2022 23:11:26

Here’s another syringe pump project, documented in a more traditional Academic fashion: **LINK**

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9058849/pdf/main.pdf

The two approaches to ‘instruction’ make for interesting comparison … but I still don’t which one is more appropriate.

MichaelG.

Oops … My closing remark on last light’s post should have read:

The two approaches to ‘instruction’ make for interesting comparison … but I still don’t know which one is more appropriate.

MichaelG.

The term "syringe pump" being new to me, I was intrigued, and followed the link Michael Gilligan offers.

It would seem the discussion so far raises its own question: is it about the machine's purpose or its manufacture?

The Italian paper's main theme, once I managed to overlook pure jargon like "schematization", appears to focus on the design. Whilst the team - or their lab technicians perhaps - built theirs, they were primarily concerned with what is necessary for making what is in effect a double-acting reciprocating pump deliver a steady flow at very finely controlled rates.

So the engineering details they give were probably to help other researchers in the same field, replicate their experiments.

It would not actually be necessary, for example, to 3D-print the parts. They could, and did, making them rather elaborate in shape because they can while they were at it; but that does not exclude others without such facilities, repeating their study, using other materials and techniques. It's essentially two syringes on a common axis, operated as I understand by a screw driven in alternating directions by a stepper-motor; an arrangement permitting fine metering. (That being the vital point. A harmonic drive such as from an eccentric would make the flow-smoothing much harder or impossible to achieve; and would be of fixed stroke. )

Mechanically, a syringe-pump like that is very simple. The syringe manufacturers have made the critical parts for you! The really clever part for you is the electronics and programming, and designing the flow-smoothing.

It is what the machine does and how, rather than how it is made, that counts.

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Incidentally, smoothing the output from a pulsing pump is not of course a new idea. The Hydraulic Ram, used for raising water from the same river that is driving it, has an air-cylinder on its output for the same reason.

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Sorry, Nigel

It was bad of me to assume that everyone would have been acquainted with the basic “syringe pump” … they are commonly seen [or perhaps hidden in plain sight] on the drip stands beside hospital patients.

Just to clarify: The contents of a syringe are dispensed, either gradually or in bursts, by a motorised device pushing the plunger.

Modern laboratory versions are more sophisticated, and typically rather pricey: **LINK**

https://www.wpi-europe.com/products/pumps--microinjection/laboratory-syringe-pumps.aspx

… and it is these that the popular ‘open source’ projects are trying to emulate.

The underlying question in my mind [which is why I started the thread] is whether those simple video instructions for assembly risked ‘throwing the baby out with the bath-water’ …

Yes, the viewer learns to assemble one, but do they understand why their version is so cheap compared with the commercial device [and does it matter?]

MichaelG.

Good question.

It comes down perhaps to whether the simple one "anyone" can make is intended as any more than an interesting little craft exercise that also teaches the operating principle.

I would though call it a serious omission if the instructions do not make clear the real purposes for these pumps, and why the laboratory or hospital version is much more sophisticated.

The Italians' paper suggests the mechanical engineering in the proper one is a small fraction of a far more complicated exercise in chemistry, hydrodynamics and computer-programming.

Somewhat analogous perhaps to making a model steam-turbine. The designs for these are reasonably advanced, but I doubt they, and the constructional details, go as far as the text-book filling, degree-level mathematics needed by the professional power-station designer.

As always the value depends on the target audience and what they expect to get out of it. Here the context is Flow Chemistry, not Mechanical Engineering. Driving a syringe with a stepper motor mounted in a 3D printed frame and a microcontroller is of considerable advantage to anyone experimenting with flow chemistry, which isn't likely to be useful to Model Engineers; our operations may be skilled, but they're also pretty basic as technology goes. (Most of what I do in my workshop would be familiar to a Victorian machinist.)

Look at the videos from the perspective of a University Chemistry Student, someone doing a PhD, or a full-blown Research Team. They're smart specialists interested in what steppers, 3d printing and computers can do for them. They're not looking for an in-depth course in any of those subjects: the message is 'complex things are possible without having to make everything yourself'.

Even though I know what Flow Chemistry, and do a bit of 3D printing, and program Arduinos in electronic projects, I didn't get the point of the Syringe Pump until Video 4.

In short, the reality of modern life is that previous learning may not be relevant today. When I left school the University of Bath had a large well-staffed workshop making and repairing experimental lab equipment. Much smaller last time I saw it, with CNC and other modernisations rather than several manual machines busy cutting metal. Industry and education need far fewer of the traditional skills common in my youth, which is why the focus of education has shifted. Today knowing how to design is far more important than making because most making doesn't depend on highly skilled craftsmen.

Dave

Your points are well-made, Dave … but I still do think that both students and potential users [*] of that cheap and cheerful device should be made aware that it might not actually have the accuracy and precision required for an experiment to pass scrutiny.

MichaelG.

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[*] and please note the closing paragraph of the page that I clipped

Edited By Michael Gilligan on 04/10/2022 11:40:31