Anyone who flies is familiar with the sensations experienced during takeoff, approach, landing, and taxi, but what you may not be familiar with is the series of devices that make this all possible, devices collectively known as actuators. Actuators are devices that convert electricity into pressure, temperature, or mechanical movements. Traditional actuator technologies like hydraulic and pneumatic systems have been around for a while, but new actuator technologies like HASEL actuators are becoming increasingly utilized in aircraft construction. What they have over the hydraulic and pneumatic systems of the past is that they are extremely lightweight so they increase fuel efficiency, reduce emissions, lower operating and maintenance costs, optimize performance, reduce noise, and provide higher levels of safety.
Take, for example, those simple flap adjustments you might have seen from the window. Flaps, edge slats, and stabilizer trim are all driven essentially by hydraulic motors. Where the hydraulic systems previously required a centralized fluid feed and cooling systems, electrohydrostatic actuators are self-contained units that have no need for external hydraulic pumping that uses extra power nor the cooling systems that further sap energy and create extra weight. They’re self-contained, so they offer fewer areas of potential leakage or failure.
In that same flap mechanism, the flap is moved by another type of actuator called a linear actuator, which converts an electric motor’s rotary movement into linear movement. This mechanism drives a stainless steel piston that can telescope outward or collapse inward to either push or pull the item to which it is attached. Another type of actuator commonly used in aircraft is the rotary actuator, which you might see used, for example, to help the nosewheel steering system pivot through the 360-degree arc required for precision turning.
Because actuators are compact in comparison to their counterparts, they become important components of the safety redundancies of aircraft. Important systems in planes require double and even sometimes triple mirror systems in case of primary failure. Jet engines are protected in the case of fire, for example, by actuators that block off the fuel supply, a safety system that requires redundancy. Duplicate actuators take up far less space and load than other comparable systems, especially lightweight actuator technologies like the metal-free HASEL actuator technology.
In fact, you can thank actuators for controlling aircraft velocity and engine speed, for increasing the angle of descent so that you can land, for opening landing gear bays, for powering the system that lowers the wheels, for that telltale reverse engine surge that says you’ve arrived, and even for opening the cargo bay doors so that your luggage makes it to the conveyors. In short, actuators make your flights cost less and keep you safer from take-off to touch-down.
About Artimus Robotics
Artimus Robotics designs and manufactures soft electric actuators. The technology was inspired by nature (muscles) and spun out of the University of Colorado. HASEL (Hydraulically Amplified Self-healing ELectrostatic) actuator technology operates when electrostatic forces are applied to a flexible polymer pouch and dielectric liquid to drive shape change in a soft structure. These principles can be applied to achieve a contracting motion, expanding motion, or other complex deformations. For more information, please visit Artimus Robotics or contact info@artimusrobotics.com.