actionnement

Actionnement, or actuation, is the process of converting an electrical, hydraulic, pneumatic, thermal, magnetic, or other control signal into physical movement or force in a mechanism. It is a fundamental function in automation, robotics, and process control, enabling devices to perform tasks such as positioning, clamping, or regulating flow. An actuator is the device that performs the actuation; it is typically paired with a controller and sensors to form a closed-loop system.

Major actuation technologies are: electric (electromechanical actuators such as motors and linear actuators, often with gearing or screws), hydraulic (fluid power cylinders capable of high force and speed for linear motion), pneumatic (air-powered cylinders suitable for light to moderate loads and fast movements), and other methods including magnetic, piezoelectric, shape memory alloys, and thermal actuators. Each technology offers different trade-offs in force, speed, precision, stroke, energy efficiency, and environmental tolerance.

In control systems, actuators are driven by power electronics or hydraulic/pneumatic controllers, and their motion is commonly monitored by sensors for feedback. Key performance metrics include available force or torque, travel speed, stroke length, positional accuracy, response time, repeatability, and lifetime. Design considerations include load characteristics, speed requirements, energy consumption, and safety.

Applications span industrial automation, robotics, aerospace, automotive systems, and consumer devices. Proper selection and integration of actuation systems influence reliability, maintenance needs, and overall system performance.