mechanisme

Mechanisme is a term used in several languages to refer to a system of moving parts that transmits motion and force to produce a desired output. In engineering, a mechanism is the component of a machine that provides motion transmission, while a broader term, machine, includes energy sources and control elements. Mechanisms consist of rigid bodies connected by joints forming a kinematic chain; motion is determined by geometry, joints, and constraints. Common categories include levers, inclined planes, screws, wedges, pulleys, wheels and axles, and more complex arrangements such as four-bar linkages, cam-and-follower systems, and gear trains. Analysts measure performance with respect to motion, force transmission, and efficiency, using concepts such as degrees of freedom, transmission ratio, and mechanical advantage.

In science and philosophy, mechanism describes the approach that natural phenomena arise from causal interactions of parts governed by physical laws. In chemistry and biology, mechanism refers to the steps and agents producing a result, for example reaction mechanisms, enzymatic mechanisms, or signaling mechanisms.

Historically, mechanistic explanations gained influence during the Scientific Revolution and shaped views in physics, biology, and medicine. Today, mechanisms are routinely designed and analyzed in engineering, often integrated with electronics and control in mechatronics. Design concerns include precision, friction, wear, backlash, tolerances, and manufacturability, all of which affect reliability and performance of a mechanism.