Automotive systems are infinitely more complex than meets the eye. Gaining a complete understanding of what occurs when a vehicle starts takes years of study, practical experience, and working with a wide range of vehicles.
A component like the actuator from a reliable supplier like RS can seem quite innocuous. But as the automotive landscape continues to change, particularly with the rise of electric vehicles, knowing about each component is critical. For instant, what role does the actuator play and what applications does it have?
What Does an Actuator Do?
The actuator is a critical component for any vehicle. Basically, it takes the digital commands sent forth by the vehicle control systems and makes it into physical actions. As vehicular technology continues to become more sophisticated, so too must the actuators sending out the commands.
Image: RS
Beyond that basic description, there are more comprehensive functions that must be broken down in order to truly understand them. Let’s take a closer look.
Transmission Shift Control
For both manual and automatic transmissions, actuators help with shifting gears. They direct hydraulic fluid while also engaging/disengaging bands and clutches. Solenoid actuators take the electrical signal from the transmission control module, regulating which gear set should be in operation. This is critical for maximum fuel economy, power delivery, and seamless gear changes.
Throttle Control
Actuators control just how much air enters the engine. What used to be purely mechanical has since shifted to an electronic throttle control (ETC) that most modern vehicles use. When a pedal is pressed, for instance, an electrical signal is sent to the actuator. Because of the actuator, smoother acceleration and better accuracy are achieved, essential for things like cruise control and traction control.
Active Suspension Systems
Active suspensions are newer but help when it comes to changing driving demands and road conditions, improving ride comfort and handling dynamics. Combined with sensors, things like road defects, vehicle speed, and cornering forces are analysed, allowing the vehicle to damper stiffness or change ride height.
Speed and Response Time
One of the more critical specifications when it comes to actuators is speed and response time. This is the time it takes the actuator to begin moving when a command is received. When it comes to safety-critical systems, speed and response time are imperative.
Actuators work to power things like anti-lock braking systems (ABS) in order to modify brake pressure. Reaction time of the actuator is measured in milliseconds, though rotating actuators can also be measured in RPM.
Force and Torque
Force and torque both play an essential role in the performance of an actuator. Torque is generally associated with rotary actuators (representing rotational force) whereas force is a more linear action like pushing or pulling.
Automotive actuators definitely need to be able to apply just enough torque or force in order to perform their duties in the most efficient way possible. The actuator has to produce enough torque to adjust the throttle valve against something like the pressure of incoming air or the force of the return spring. The underlying responsibilities of the actuator are too numerous for one space but rest assured they handle enough responsibilities that your car, van, or truck couldn’t operate without it.
An Unsung Hero of Automotive Systems
It is hard for a particular component to get proper attention, but the actuator is deserving. Think of it as the signal caller of the vehicle, responsible for telling the various systems what to do and when. Without it, a trip down the street would look a whole lot different.
