Nuts and Bolts

Biomedical devices are often connected loosely to protect a patient. A pulse oximeter, used to detect blood oxygenation, is connected to a patient’s finger with deliberate weakness, preventing injury should someone trip over the cable. The clips that hold lobster traps together are designed to corrode after one fishing season. When traps are lost o

Crack propagation in a material increases with the sharpness of the tip of the crack. Drilling a hole at the tip makes a crack less sharp and distributes stresses over a larger area and in more directions, discouraging the crack from lengthening. Rounding of corners in building products, machine parts, furniture, and even the windows of ships and a

Many of humanity’s tools, used for centuries all over the world, incorporate leverage—scissors, pliers, door handles, wheelbarrows, fishing rods, and more. Levers are one of our simplest, yet greatest, inventions.