Japan Aerospace Exploration Agency (JAXA), ShinMaywa Industries Ltd, Oita University, Nippon Bunri University, Ibaraki University and Shizuoka University announced that they have developed "one of the world's best" small-size, high-efficiency motors.
The mass of the motor is 25g, and it can be continuously operated with an output of 50W. It can be operated with an efficiency of 80% or higher in a wide rotation speed range (from low to high rotation speeds) and a wide output range (from low to high outputs).
At a rotation speed of 15,000rpm or higher, the efficiency of the rotor is 85% or higher in a wide range. Also, it generates a small amount of heat.
The motor is expected to be employed for devices for space exploration first. On the surface of the moon, which is in a vacuum state, and the surface of Mars, where air is thin, it can hardly be expected that heat is dissipated by convection. So, a high-efficiency motor that does not generate much heat is required.
As for applications on the earth, the motor can be used for (1) drones, whose flight time can be extended with a light-weight motor, (2) robot joints, (3) precision measurement devices, whose temperature should not fluctuate, etc.