Semiaktiva

Semiaktiva is a term used in Indonesian-language technical literature to describe a class of systems and devices that operate in a semi-active mode. It is used primarily in control theory and vibration damping. The term contrasts with passive systems, which require no power, and fully active systems, which draw power continuously to produce motion or force.

Semiactive devices adjust a response parameter—typically damping, stiffness, or natural frequency—through controlled actuation while relying on limited power input. They achieve adaptive behavior by monitoring system state or external disturbances and making real-time adjustments, but do not supply energy to the load in the same way as fully active systems. This yields energy efficiency gains and reduced equipment stress.

Common applications include semi-active suspensions in automobiles, where dampers vary damping in response to road conditions; seismic or wind vibration control in civil engineering, where dampers counteract oscillations; and aerospace or machinery where vibration suppression improves performance and safety.

Design considerations involve control algorithms that are robust to uncertainties, fast enough actuation, and reliability under variable environmental conditions. Trade-offs include response speed, dynamic range, and cost, as semi-active solutions must balance improved performance against limited actuation capacity.

See also: active control, passive damping, semi-active control systems.