The triangle doesn't bend because each side experiences only one force at a time. When used properly, triangles are the most stable and rigid shapes used in construction today.

Principal Investigator Dr Firat Guder, from the Department of Bioengineering at Imperial College London, said: “Prosthetic limbs are often uncomfortable because they have a fixed rigid shape.

The triangle doesn't bend because each side experiences only one force at a time. When used properly, triangles are the most stable and rigid shapes used in construction today.