Advantages
PAMs are very lightweight because their main element is a thin membrane. This allows them to be directly connected to the structure they power, which is an advantage when considering the replacement of a defective muscle. If a defective muscle has to be substituted, its location will always be known and its substitution becomes easier. This is an important characteristic, since the membrane is connected to rigid endpoints, which introduces tension concentrations and therefore possible membrane ruptures.
Another advantage of PAMs is their inherent compliant behaviour: when a force is exerted on the PAM, it "gives in", without increasing the force in the actuation. This is an important feature when the PAM is used as an actuator in a robot that interacts with a human, or when delicate operations have to be carried out.
In PAMs the force is not only dependent on pressure but also on their state of inflation. This is one of the major advantages; the mathematical model that supports the PAMs functionality is a non-linear system, which makes them much easier than conventional pneumatic cylinder actuators to control precisely. The relationship between force and extension in PAMs mirrors what is seen in the length-tension relationship in biological muscle systems.
The compressibility of the gas is also an advantages since it adds compliance. As with other pneumatic systems PAM actuators usually need electric valves and a compressed air generator.
The loose-weave nature of the outer fiber shell also enables PAMs to be flexible and to mimic biological systems, If the surface fibers are very badly damaged and become unevenly distributed leaving a gap, the internal bladder may inflate through the gap and rupture. As with all pneumatic systems it is important that they are not operated when damaged.
Read more about this topic: Pneumatic Artificial Muscles
Famous quotes containing the word advantages:
“If we help an educated man’s daughter to go to Cambridge are we not forcing her to think not about education but about war?—not how she can learn, but how she can fight in order that she might win the same advantages as her brothers?”
—Virginia Woolf (1882–1941)
“No advantages in this world are pure and unmixed.”
—David Hume (1711–1776)
“In 1845 he built himself a small framed house on the shores of Walden Pond, and lived there two years alone, a life of labor and study. This action was quite native and fit for him. No one who knew him would tax him with affectation. He was more unlike his neighbors in his thought than in his action. As soon as he had exhausted himself that advantages of his solitude, he abandoned it.”
—Ralph Waldo Emerson (1803–1882)