The human leg is a complex and versatile machine. Designing a prosthetic (artificial) device to match the leg’s capabilities is a serious challenge. Teams of scientists, engineers, and designers around the world use different approaches and technologies to develop prosthetic legs that help the user regain a normal, active lifestyle.
Studying the Human Gait Cycle: Each person has a unique way of walking. But studying the way humans walk has revealed that some basic mechanics hold true for just about everyone. Scientists analyze how we walk by looking at our “gait cycle.” The gait cycle consists of two consecutive strides while walking, one foot and then the other. By breaking the cycle down into phases and figuring out where …show more content…
In the past, most designs were basic and relied on the user learning how to walk properly. This effort required up to 80 percent more energy than a normal gait and often made walking with an older prosthetic leg quite a work out! The knee joint in those older designs was often a hinge that let the lower leg swing back and forth. The hinge could also lock in place to keep the leg straight and support the user's weight to make standing easier. This type of system worked relatively well on level surfaces, but could be difficult to use on inclines, stairs, irregular terrain (like a hiking trail), or slippery surfaces. Current prosthetic legs have improved upon old designs by employing hydraulics, carbon fiber, mechanical linkages, motors, computer microprocessors, and innovative combinations of these technologies to give more control to the user. For example, in some designs, a device called a damper helps to control how fast the lower leg can swing back and forth while walking. The damper accomplishes this by changing the knee’s resistance to movement as needed. New knee designs allow users to walk, jog, and with some models, even run with a more