Sometimes, you need to set yourself really strict constraints in order to come up with the most creative innovations.
This is exactly what Manu Prakash did with his team at Stanford when trying to make a better, cheaper way to test blood samples in poorer countries.
Check out his video above.
He was trying to find a replacement for a vital but very expensive piece of equipment; a centrifuge, which is used to separate blood into its various components for analysis by spinning a sample very quickly.
This is an essential step in testing for diseases like HIV or Malaria.
But commercial centrifuges are heavy, bulky, can cost thousands of dollars and require electricity to run, which is not always available in remote parts of the world.
Manu saw the need firsthand during a trip to Uganda.
“We were out in a primary health center talking to health care workers and we found a centrifuge used as a doorstop because there’s no electricity.”
So he tasked his team with developing a replacement, and set out the three criteria it needed to achieve:
- It cannot require any electricity
- It needs to be light and portable enough to fit inside someone’s pocket
- It had to cost less than $1 in parts
He and his team started looking at things that spin from human power alone and came across a children’s toy called a whirligig.
This toy has been around for thousands of years, but it was only after they took the basic features and adjusted them into their own design that they saw this simple device could spin at more than 125,000 revolutions per minute (RPM), more than enough to separate out the components of blood samples.
By comparison, a Formula 1 engine spins at about 15,000 RPM.
And best of all, it only cost about $0.20 in materials to produce, meeting all of his initial criteria.
At the moment, the design is used for analysing samples for malaria, but the team is working on versions to test for other diseases as well.
It just goes to show that sometimes you need to set difficult constraints in order to come up with the most creative solutions.