ENGINEERING IN CHARGE
Do you realise that every time you take a step, the bones in your hip are subjected to forces between four and five times your body weight? When you are running, this force is increased further still.
What happens if, through disease, a hip-joint ceases to be able to resist such forces? Like all fantasies, the Bionic Man has an element of reality in and for many years, hip-joints and other body joints have been replaceable partially or completely. It is, after all, a simple ball and socket joint; it has certain loads imposed on it; it needs reliability over a defined life, and it must contain materials compatible with the working environment.
Any engineer will recognise these as characteristic of a typical engineering problem, which doctors and engineers have worked together to solve in order to bring a fresh lease of life to people who would otherwise be incapacitated. This typifies the way in which engineers work to help people and create a better quality of life.
The fact that this country has the most efficient agricultural industry in the world is another prime example. Mechanical engineers have worked with farmers, horticulturalists and biologists to produce fertilisers, machinery and harvesting systems. The paintings of Brueghel show farmers in the sixteenth century wading through shoulder-high cereal crops. This team effort has now produced crops uniformly waist-high or less so that they are more suitable for mechanical harvesting.
Similar advances with other crops have released people from hard and boring jobs for more creative work, while machines harvest crops more efficiently with less waste. 25 Providing more food for the rapidly increasing population is yet another role for the mechanical engineer.
A. What do the following refer to?
1. ‘such forces’ (line 5):
2. ‘if (line 6):
3. “If (line 7):
4. ‘another prime example’ (line 16): another prime example of
5. ‘this team effort’ (line 20): the team effort of
B. What are the four characteristics which make the replacement of a hip-joint to be considered as a typical engineering problem?