High performance, lightweight electromechanical actuators which are optimised for helicopters’ actuation systems, have been introduced by INMOCO, but are also designed as a highly suitable technology transfer in other appropriate applications.
Helicopter actuation systems include rotor blade trailing edge flaps, onboard cargo loading beams and gear and access doors. In helicopters, actuation systems perform safety critical functions, yet the associated equipment needs to be compact and lightweight, as well as superbly reliable and compliant with all necessary legislation.
Gerard Bush of INMOCO explained that the characteristics required for airborne applications may also be desirable in other areas.
“Many types of turbine blades have similar dynamic requirements to helicopter rotors. For instance wind turbine blades are large so may flex and vibrate in a manner similar to helicopter blades, while tip speed issues may need to be addressed in any high speed rotational mechanism.”
Looking at a specific example, large helicopter rotor blades can suffer from severe vibration. To counteract these vibratory air loads, some established helicopter designs employ oscillating trailing edge flaps to reduce vibratory hub loads, thus increasing flight range and workload. However, there is a weight consideration with actuators based on older technology.
“Weighing less than one kilo, Diakont’s rotary electromechanical actuators are ultra-compact and allow helicopter designers to take full advantage of trailing edge flap technology,” noted Bush. “They have a rated torque of up to 18Nm and can cope with vibration frequencies up to 19Hz. In addition to its successful track record in helicopter actuation applications, Diakont has also applied these advanced rotary actuators to other industries and applications.”
INMOCO will also be promoting Diakont’s landing gear and access doors actuation system. These comprise a dual-redundant, closed looped kinematic chain coupled with roller screw gears. Each roller screw gear is installed on a shaft connected to a dual-redundant motor. Multiple roller screws are used to evenly distribute motor torque throughout the physical system. This fully electric design is lightweight and low maintenance, characteristics also highly attractive in many other demanding application areas.
Bush continued: “INMOCO is very excited about possibilities for Diakont’s electromechanical actuators for onboard beam linear actuation, as used for loading and unloading helicopter cargo. These 635mm stroke units weigh only 12.5kg, yet produce a 3,100N force and operate at 24mm/sec. As such there are many potential linear motion applications in a very wide range of industries.
“Technology transfer always has the potential to offer a fast, effective and trouble-free solution to engineering projects. Often the end-user will think the only way forward is to develop a bespoke system from first principles, then is delighted to find there is an off-the-shelf product waiting to be borrowed from another industry.”