Category Archives: everyday engineering examples

Letting the grass grow while learning some engineering

Photograph of ATCO 17-inch petrol lawnmower in a gardenLast month was #NoMowMay during which we were encouraged to let the grass grow and allow bees, butterflies and other wildlife to thrive unmolested by your lawnmower.  Our townhouse in the centre of Liverpool does not have enough space for a lawn so I have not mown a lawn since we moved here from the USA nearly a decade ago.  In the USA we followed the convention and maintained our front lawn as manicured green carpet by watering daily, mowing weekly and feeding it monthly during the summer.  An automatic sprinkler system looked after the watering and a lawn service provided monthly doses of chemicals; however, we walked up and down behind the lawnmower each week.  Much to my disappointment, our garden was not really large enough to justify a garden tractor or sit-on mower which has been a dream since I learnt my first self-taught engineering by ‘repairing’ my father’s green ATCO lawnmower when I was about 10 or 12.  I was not allowed lift the bonnet or hood of the family car; and so as the only other piece of mechanical engineering in the garage that has an engine, the lawnmower became the focus of my attention.  I suspect that old lawnmower did not run any better as a result of my ministrations but I certainly understood how an internal combustion engine worked by the time I went to university.  I am an enthusiastic supporter of letting the grass grow, perhaps with a mown pathway so that the lawnmower has to be re-assembled periodically by whichever budding engineer has dismantled your lawnmower.

Source: Joy Lo Dico, How the lawn became a no-mow area, FT Weekend, 29/30 May 2021.

Image: An ATCO 17-inch petrol lawnmower similar to the one mentioned above, from

Democratizing education

One motivation for developing Massive Open Online Courses (MOOC) has been to democratize education by giving everyone access to knowledge often presented by leading professors.  It was certainly one reason why I developed and delivered two MOOCs on ‘Energy: Thermodynamics in Everyday Life‘ in 2015/16 and ‘Understanding Super Structures’ in 2017.  The workload involved in supporting thousands of learners around the global is not insignificant and was unsustainable for me so I gave up after running them for a couple of years despite the intangible rewards [see ‘Knowledge spheres‘ on March 9th, 2016 and ‘A liberal engineering education‘ on March 2nd, 2016] . However, I incorporated the MOOC on energy into my undergraduate module on thermodynamics to create a blended approach to learning [see ‘Blended learning environments‘ on November 14th, 2018].  This paid dividends for me when the pandemic forced our campus into lock-down in the middle of semester last March and I already had a large number of bite-sized activities available online for our students.  Most universities have had to move their teaching online due to the pandemic; but not all students are able to access the online materials as easily others.  The Booker shortlisted novelist, Tsitsi Dangarembga has reported how one of her neighbours has struggled to access resources recommended to him by lecturers at his college in Bulawayo due to the cost and unreliability of Wi-Fi in Zimbabwe.  She tried to help him by registering him for her hotspot package but, in common with many students, he studies mainly at night when hotspot venues are closed.  The maps shows the global distribution of learners in one of the Energy MOOCs that I delivered and you can see the holes in Africa and South America which, at the time, we thought might be due to a lack of computer and internet access and Dangarembga’s account seems to support this hypothesis.  So, we designed our second MOOC on Structures to be accessible via a mobile phone by using fewer videos and more audio clips that could be quickly downloaded and listened to offline.  Unfortunately, we ran out of resources to complete the research on whether it was accessed more successfully in those grey areas on the map; however, the audio recordings were unpopular with the more traditional audience in the USA and UK who gave us immediate and vocal feedback!


Tsitsi Dangarembga, Protest and prizes, FT Weekend, 26/27 September 2020.

Patterson EA, Using everyday engineering examples to engage learners on a massive open online courseInternational Journal of Mechanical Engineering Education, p.0306419018818551


Homework practical exercises in structural mechanics

Last week I wrote about the practical exercises that I have been setting as homework in my first year undergraduate course on thermodynamics.  The instruction sheets that I published had been used by thousands of learners on my MOOC, Energy! The Thermodynamics of Everyday Life; and slightly modified versions had been used by more than a thousand students at the University of Liverpool.  A few years ago, I produced another MOOC called ‘Understanding Superstructures’ which also contained three practical exercises for online learners to perform in their kitchens.  I have not used them as part of a blended undergraduate course but nevertheless they have been completed by hundreds of participants in the MOOC.  I have decided to share them for colleagues to use in support of first year courses on the Mechanics of Solids or the Mechanics of Structures.  There is strong food flavour and no additional equipment is needed. Please feel free to use them to support your teaching.

Instruction sheets for thermodynamics practical exercises as homework:

Structural collapse | Crushing and toppling of towers

Stress concentrations | Newspaper tension tests

Residual stresses | Bending carrots





Thermodynamics labs as homework

Many of my academic colleagues are thinking about modifying their undergraduate teaching for next academic year so that they are more resilient to coronavirus.  Laboratory classes present particular challenges when access and density of occupation are restricted.  However, if the purpose of laboratory classes is to allow students to experience phenomena, to enhance understanding, to develop intuition and to acquire skills in using equipment, making measurements and analysing data, then I believe this can achieved using practical exercises for homework.  I created practical exercises, that can be performed in a kitchen at home, as part of a Massive Open Online Course (MOOC) about thermodynamics [See ‘Engaging learners on-line‘ on May 25th, 2016].  I have used the same exercises as part of my first year undergraduate module on thermodynamics for the past four years with similar levels of participation to those experienced by my colleagues who run traditional laboratory classes [see ‘Laboratory classes thirty years on‘ on May 15th, 2019].  I have had a number of enquiries from colleagues in other universities about these practical exercises and so I have decided to make the instruction sheets available to all.  Please feel free to use them to support your teaching.

The versions below are from the MOOC entitled ‘Energy: Thermodynamics in Everyday Life‘ and provide information about where to obtain the small amount of equipment needed, and hence are self-contained.  Although the equipment only costs about £20, at the University of Liverpool, we lend our students a small bag of equipment containing a measuring beaker, a digital thermometer, a plug-in power meter and a plumber’s manometer.  I also use a slightly different version of these instructions sheets that provide information about ‘lab’ reports that students must submit as part of their coursework.

I reported on the initial introduction of blended learning and these practical exercises in Patterson EA, 2019, Using everyday examples to engage learners on a massive open online course, IJ Mechanical Engineering Education, 0306419018818551.

Instruction sheets for thermodynamics practical exercises as homework:

Energy balance using the first law of thermodynamics | Efficiency of a kettle

Ideal gas behaviour | Estimating the value of absolute zero

Overall heat transfer coefficient | Heat losses from a coffee cup & glass