AST Motor™ is a new type of high-performance motor that incorporates a coil developed with our unique layering technology called AST COIL®. Aster has succeeded in forming the coil, which used to be wound with copper wire, with sheet copper or aluminum. This has resulted in an overwhelmingly high occupancy rate, enabling dramatically higher efficiency, higher output, smaller size, and lighter weight. At the same time, this innovative technology has dramatically improved recycling efficiency.

What is the "AST motor"?



Ultra-light motors

with aluminum coils



Characteristics of AST motor

The AST motor has greatly improved the heat dissipation and resistance of the coil because of the special structure of the AST coil. Therefore, it is expected to play an active role in various fields, as they not only make motors smaller, lighter, and more efficient but also enable higher output and improved response performance. In addition, the recycling efficiency of the coils is also much improved, which makes it an earth-friendly motor.


-Innovative motor with aluminum coil-

AST motors are made of aluminum and are constructed with coils that have a larger cross-sectional area than conventional wound coils. As a result, it is possible to significantly reduce the size and weight of the motor while achieving performance superior to that of conventional coils. This technology will help us to get rid of our dependence on copper resources, which are feared to be depleted worldwide.

  • Aluminum coils perform far better than conventional wound copper coils

  • Aluminum resources are less vulnerable to depletion than copper.

  • Aluminum (a.k.a. the king of recycling) has a low melting point, and CO₂ emissions during recycling are much lower than copper.

Ultra-light motors using aluminum coils

-Respond quickly and sustain the peak output for a long time-

AST motors have significantly surpassed the output density of conventional motors by increasing the coil occupancy. In addition, the large cross-sectional area of the AST coils allows a large current to flow, which improves the responsiveness of the motor. Furthermore, the heat dissipation is significantly improved by the high occupancy ratio, enabling the peak output of the motor to be maintained for a longer period of time than existing motors.

4kW Comparative example of power density for EV motor (same output)

4kW Comparative example of responsiveness and peak output persistency (same output)


Conventional coil


AST coil


-Over 90% recycling efficiency-

When winding coils are recycled, the recycling efficiency remains low due to wasteful disposal during disassembly and a large amount of insulating film per coil metal material. However, AST coils are assembled in a block shape and can be easily disassembled from the motor, thus eliminating wasteful disposal during disassembly. In addition, AST coils are made of stacked metal plates with a large cross-sectional area, and the surface area of the coil is less than half that of conventional coils, which means that the amount of insulating film can be drastically reduced. Therefore, over 90% of the metal material can be recycled from AST coils.



Field of adaptation

Aster Co., LTD. can make a significant contribution to the global environment by applying AST motor technology to the fields of power generation and mobility. In addition, the large cross-sectional area and high occupancy of the coils allow a large amount of current to flow at once, and this structure is expected to play an essential role in the medical and industrial equipment fields, which require high output and responsiveness.
Furthermore, the AST motor can be sealed since the heat dissipation is greatly improved by the stacked coils. As a result, the AST motor is the first in the world to achieve dust and water resistance (IP67 certification), which is essential for safe and secure drone flights. This performance will greatly improve the flight reliability of "flying cars," the future of mobility. Our Aster technology is an important solution for protecting the global environment, exploring new applications, and continuously realizing people's dreams.



Mobility field

Medical equipment / robot

Industrial equipment / factory automation

[Example] Drone Motor
A revolution in sky safety

- the world's first to achieve IP67 -

The drone is used not only for capturing beautiful scenery from the sky, but also for surveying and transporting heavy objects in places such as construction sites and agriculture. In the future, when drones and flying cars become common, Aster's AST motors will work hard to develop technologies that will make our society even safer and more secure than it is today.