Large mechanical structures such as oil rigs, bridges, pipelines, chemical
plants, nuclear installations and aircraft may in the future be equipped
with ‘fuses’ which give early warnings of stresses in the structure that
could lead to catastrophic failures. Just as an electrical fuse cuts out
when a circuit is overloaded, the mechanical ‘fuses’ share the stresses
experienced by thestructure to which they are attached, and gradually snap
as preset stress levels are successively exceeded.
The so-called ‘fatigue fuse’ was launched earlier this month by Tensiodyne,
a company based at Sarasota in Florida. It is around the size and shape
of a book of matches and consists of a flat metal frame housing five parallel
strips of metal (the ‘matches’).
Each strip has different nicks, indentations and fissures cut into it,
which mimic the condition of the most stressed parts of any structural component.
So the strips reflect the stresses experienced by flaws in the structure,
such as miniature cracks, or by features where stresses are greatest, such
as boltholes. Using an epoxy resin, engineers stick the fuse to strategic
points on the structure, where it effectively records the ‘fatigue histories’
of the components.
Some of the strips have nicks in them which make them weaker than the
others, and these gradually snap, one by one. This gives the inspector an
‘hourglass’, showing how much longer the structure can be left before it
requires maintenance or complete replacement.
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Raymond de la Veaux, the executive vice president of engineering at
Tensiodyne, says the fuses can be used alone and inspected regularly, or
connected to an electronic remote monitoring system which keeps anautomatic
check on the fuses. The monitoring system was developed by Hughes Aircraft
Company and is potentially useful for large structures such as bridges and
oil rigs, where access to remote components is difficult and sometimes dangerous.
De la Veaux says that while the fuses cost $400 each – which includes
calibration for a specific installation and the necessary adhesive – they
save money in that fewer inspections are required. Alan Clayton, head of
structural performance engineering at AEA Technology in Risley, Cheshire,
expects the fuses will be useful, but will only catch on once potential
users have confidence in their performance.
![Astronomers have long known that understanding how star clusters come to be is key to unlocking other secrets of galactic evolution. Stars form in clusters, created when clouds of gas collapse under gravity. As more and more stars are born in a collapsing cloud, strong stellar winds, harsh ultraviolet radiation and the supernova explosions of massive stars eventually disperse the cloud, and their light can bear down on other star-forming regions in the galaxy. This process is called stellar feedback, and it means that most of the gas in a galaxy never gets used for star formation. Researching how star clusters develop can answer questions about star formation at a galactic scale. Now, the state of the art has been further developed with both Hubble and Webb working together to provide a broad-spectrum view of thousands of young star clusters. An international team of astronomers has pored over images of four nearby galaxies from the FEAST observing programme (#1783), trying to solve this mystery. Their results show that it is the most massive star clusters that clear away their gaseous shroud the fastest, and begin lighting their galaxy the earliest. The team identified nearly 9000 star clusters in the four galaxies in different evolutionary stages: young clusters just starting to emerge from their natal clouds of gas, clusters that had partially dispersed the gas (both from Webb images), and fully unobstructed clusters visible in optical light (found in Hubble images). With Webb???s ability to peer inside the gas clouds, they were able to then estimate the mass and age of each cluster from its light spectrum. This image shows a section of one of the spiral arms of Messier 51 (M51), one of the four galaxies studied in this work, as seen by Webb???s Near-Infrared Camera (NIRCam). The thick clumps of star-forming gas are shown here in red and orange, representing infrared light emitted by ionised gas, dust grains, and complex molecules such as polycyclic aromatic hydrocarbons (PAHs). Within these gas complexes, each tens or hundreds of light years across, Webb reveals the dense, extremely bright clusters of massive stars that have just recently formed. The countless stars strewn across the arm of the galaxy, many of which would be invisible to our eyes behind layers of dust, are also laid bare in infrared light. [Image description: A large, long portion of one of the spiral arms in galaxy M51. Red-orange, clumpy filaments of gas and dust that stretch in a chain from left to right comprise the arm. Shining cyan bubbles light up parts of the gas clouds from within, and gaps expose bright star clusters in these bubbles as glowing white dots. The whole image is dotted with small stars. A faint blue glow around the arm colours the otherwise dark background.]](https://images.newscientist.com/wp-content/uploads/2026/05/13114322/SEI_296271016.jpg)
