How a Small Electric Actuator Operates Automotive Headlights

Christopher Nook by Christopher Nook

Aside from mechanics and car buffs, most people who drive automobiles have no idea that small electric actuators—also known as mini actuators—are at work, performing a variety of automotive functions that are simply taken for granted


Aside from mechanics and car buffs, most people who drive automobiles have no idea that small electric actuators—also known as mini actuators—are at work, performing a variety of automotive functions that are simply taken for granted. One of the more interesting automotive actuator applications involves headlights that move to track and illuminate the road, a feature that has become prevalent in many high-end models.

This article will examine how a small electric actuator is used to perform this and other automotive functions.

Headlight Motors and Leveling Systems

Most headlights are static—they don’t move—and maintain the position and orientation of the vehicle on which they are mounted. However, on many vehicles, the pair of headlights can move—either up and down or side to side—to focus the beams of light on curving or undulating road surfaces more effectively. This movement is controlled by a small actuator that is driven by a permanent magnet motor.

The headlight motor and actuator control the individual positioning of the vehicle’s headlights. This is typically done by an electronic system via the cam-operated switch that controls each headlight motor, and also by a switch on the car’s dashboard.

Mini electric linear actuators are the preferred option for this application because they convert energy into different types of linear motion, just like standard actuators, but in small, envelopes. Because they are so much smaller than standard actuators, mini actuators are perfect for providing linear actuation in tight, compact spaces, like an automotive headlight mount.

Small actuators also drive automatic headlight leveling systems, which adapt the angle of inclination of the headlamp to the position of the vehicle on the road without intervention by the driver. Headlight leveling systems are required by law for cars with xenon headlamps, and come in two types: semi-static and dynamic systems.

With semi-static headlight leveling systems, headlamp leveling corrects only changes in inclination caused by changes in load. With dynamic headlight leveling systems, which are used on cars with xenon headlamps, the system reacts to changes in inclination related to driving, including acceleration and braking.

Other Electric Actuator Uses in Automobiles

Actuators have played such an important role in automobile evolution that the modern car as we know it today would not exist without them. In the past, cars had only analog mechanical actuators, which enabled manual winding up and down of windows, and manual seat adjustments. The advent of the mini electric actuator has ushered in a proliferation of possible automotive applications. If fact, today’s average car has more than 100 hydraulic, pneumatic, and actuators within it.

Helix NEMA 17 Electric Actuator

In addition to headlight positioning systems, actuators:

  • Make windshield wipers work.
  • Lock car doors.
  • Open and close hoods and trunks.
  • Actuate the car’s throttle, which makes it go.
  • Actuate a car’s parking brake
  • Control fuel injectors.
  • Index gearboxes and provide clutch control.
  • Extend and contract audio system components, such as sliding doors and covers.
  • Open gas cap covers.
  • Drive power steering and power brake systems.


Use Helix Actuators for Automotive Linear Motion Control Applications

Contact Helix Linear Technologies for your automotive linear actuator needs. Helix Linear has supplied the electric linear actuators that have become commonplace in many of today’s automobiles for many years. With Helix Linear, you will work with a partner that brings years of experience, top-notch engineering expertise, and innovative solutions to bear in solving your most challenging linear actuator requirements.


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Additional Reading

Electric Actuator or Pneumatic Actuator?

Find the Air in Your Ways - Go Electric

Top 10 Benefits of an Electric Linear Actuator