What is the main purpose of an actuator in a machine?

An actuator's primary function is to convert various forms of energy, such as electrical, hydraulic, or pneumatic, into mechanical motion. This mechanical motion allows the actuator to perform tasks such as opening a valve, moving a lever, or positioning a component within a machine. Actuators play a crucial role in automation, enabling precise control over machinery by translating control signals into physical movements in order to execute specific actions.

In contrast, the other options describe different roles within a machine. Storing electrical energy for later use pertains to components like batteries or capacitors. Measuring the speed of a mechanism involves sensors or tachometers, which are designed to provide feedback on the operation of machines rather than actively move or change positions. Supplying power to additional components may refer to power supply units or distribution systems that provide energy but do not convert that energy into movement. Each of these functions is important, but they do not embody the primary objective of an actuator.