Percy Shaw - Inventor and developer of the Cats Eye - road safety installation seen on millions of roads around the world. - Martin Dicks - innovator of the 'Intelligent Cats-Eys - cats eyes that sense and inform - contributing to traffic safety - Inventors, Inventions, Engineer and Engineering, Designers & Designing - Engineering, Design & Technology On The Web support resource for students and teachers of Design & Technology at KS3, KS4, A-Level and beyond. Mr Richmond's help pages !
Percy Shaw’s story is a classic story of observation and thought culminating in an invention that serves a distinct need. There are several stories that tell of Percy Shaw noticing that the tramlines were visible as they disappeared into the fogs that occurred far more
frequently in thepollution of the early part of the 20th century than they do now – in our times of cleaner air and environmental awareness. Industrial smogs occurred as individual particles suspended in the atmosphere gave a ‘nucleus’ onto which droplets could form - The resultant fogs could be so thick that seeing only a few yards along the road was virtually impossible. What really was needed was a cheap way of ‘lighting’ - or ‘marking out‘ the road ahead. Another tale tells of Shaw seeing the light bouncing back from a cat’s eyes sitting at the side of the road – whichever is true – if either – the inspirational stimulus for such inventions frequently does come from such banal and innocuous occurrences.
His invention ( and patent of 1935 ) for two self-cleaning glass and metal beads; the beads depressed and brushed against their moulded housing (and cleaned too by rainwater squeezed out at the same time) as traffic ran over the inserts placed into the road surface, was ingenious and made a fortune for Shaw.
The invention has been used in roads all over the world and the trade-name of ‘Catseyes’ ® is understood by almost everyone that uses hard-surfaced roadways. Only fairly recently has a ‘challenger’ come onto the scene. The‘intelligent catseye’ picks up the light from oncoming vehicles which then triggers a timed light output to show red to any following cars – in the way that a red train signal tells that a train is on the section of line ahead. Alternatively, solar powered LEDs can remain illuminated from dusk until dawn. The power for the electronics most usually now comes from a solar charged cell repeatedly refreshed during the daylight hours - with only a very low power output an adequate charge can be stored to allow the unit to work for sufficient time until the next recharge.