Thirty-three months ago (see ‘Finding DIMES‘ on February 6th, 2019) we set off at a gallop ‘to develop and demonstrate an automated measurement system that integrates a range of measurement approaches to enable damage and cracks to be detected and monitored as they originate at multi-material interfaces in an aircraft assembly’. The quotation is taken directly from the aim of the DIMES project which was originally planned and funded as a two-year research programme. Our research, in particular the demonstration element, has been slowed down by the pandemic and we resorted to two no-cost extensions, initially for three months and then for six months to achieve the project aim. Two weeks ago, we held our final review meeting, and this week we will present our latest results in the third of a series of annual workshops hosted by Airbus, the project’s topic manager. The DIMES system combines visual and infrared cameras with resistance strain gauges and fibre Bragg gratings to detect 1 mm cracks in metals and damage indications in composites that are only 6 mm in diameter. We had a concept design by April 2019 (see ‘Joining the dots‘ on July 10th, 2019) and a detailed design by August 2019. Airbus supplied us with a section of A320 wing, and we built a test-bench at Empa in Zurich in which we installed our prototype measurement system in the last quarter of 2019 (see ‘When seeing nothing is a success‘ on December 11th, 2019). Then, the pandemic intervened and we did not finish testing until May 2021 by which time, we had also evaluated it for monitoring damage in composite A350 fuselage panels (see ‘Noisy progressive failure of a composite panel‘ on June 30th, 2021). In parallel, we have installed our ‘DIMES system’ in ground tests on an aircraft wing at Airbus in Filton (see image) and, using a remote installation, in a cockpit at Airbus in Toulouse (see ‘Most valued player performs remote installation‘ on December 2nd, 2020), as well as an aircraft at NRC Aerospace in Ottawa (see ‘An upside to lockdown‘ on April 14th 2021). Our innovative technology allows condition-led monitoring based on automated damage detection and enables ground tests on aircraft structures to be run 24/7 saving about 3 months on each year-long test.
My research includes work on developing digital twins [see ‘Digital twins that thrive in the real world‘ on June 9th, 2021] of aircraft, power stations and other engineering systems. And I am aware of similar work in other disciplines [see ‘Digital twins could put at risk what it means to be human‘ on November 18th, 2020]; but I was surprised to learn about the demand for digital clothing. Three-dimensional virtual spaces or metaverses exist in computer games, chat rooms and more recently virtual spaces designed for socialising and shopping that are populated by avatars that need to wear something. So, some fashion brands are producing digital clothing and charging you for the privilege of attiring your avatar with their logo. In other words, you can buy clothes that don’t exist for people who are not real. However, DressX has gone a step further producing a ‘digital-only collection’ of clothing for your digital twin or, at the moment, two-dimensional images of real people. So, now you can buy clothes that don’t exist, superimpose them on pictures of real people, and upload the results to social media. Perhaps it’s not as crazy as it seems at first because it might alleviate the need for fast fashion to produce single-use real clothes at enormous cost to the environment. However, dressing up your digital twin does not seem to offer the same level of anticipation and excitement as getting dressed up yourself. (Except in a lockdown? Ed)
A week has just raced past and it’s time to write a blog post – the 479th. The first twenty or so posts were published randomly when I thought of something to write. Only the last 457 have been published regularly on Wednesdays. However, given the average life expectancy of a male in Britain is 4225 weeks, that implies I have been writing a weekly post for slightly more than a tenth of my life expectancy. More depressing, considering the speed at which weeks are racing past me, is that I probably only have about 1000 weeks left. A thousand is a big number if you are trying to count sheep to get to sleep but quite a small number when thinking about the life of the universe [see ‘Will it all be over soon?‘ on February 2nd, 2016]. I have mixed feelings about my perception of a thousand weeks of life remaining. It seems short enough to make me pause, think about slowing down so that the weeks do not fly past so quickly and to write about it. But it is probably not short enough to induce me to make dramatic changes to my lifestyle. Perhaps the most likely effect will be to increase my awareness of the need to make time for the important things in work and life. At work that probably means being more focussed on the big picture while in life it suggests focussing on the atelic activities, i.e. those pursued for their own sake, such as our weekly walk up Moel Famau.
We sense the passage of time by the changes that occur around us (see ‘We inhabit time as fish live in water‘ on July 24th, 2019) and these changes are brought about by processes that generate entropy. Entropy is often referred to as the arrow of time because forwards in time is always the direction in which the entropy of the universe increases, as demanded by the second law of thermodynamics (see for example ‘Subtle balance of sustainable orderliness‘ on June 22nd, 2016). The temperature in a refrigerator is sufficiently low that it slows down the processes of decay in the food stored in it (see’ Life-time battle‘ on January 30th, 2013) which effectively slows down time locally in the fridge. However, there is a price to pay because the process of creating of the cold zone in the fridge increases the entropy in the universe and moves the universe infinitesimally closer to cosmic heat death (see ‘Will it all be over soon?‘ on November 2nd, 2016). So, cooling the food in your fridge slows down time locally but brings the end of the universe a tiny bit closer. Perhaps that’s not worth worrying about until you start thinking about how many fridges there are in the world (about half a billion are sold every year) and how many other devices are generating entropy. The end of the universe might still be billions of years away but all that anthropogenic entropy is contributing to the increase in the temperature of the Earth’s ecosystem.