The new P532 series disc magnet step motor from Portescap has a diameter of 52 mm, length up to 55 mm, and rated torque of 0.2 Nm (boosted up to 0.5 Nm) to deliver dynamic performance including acceleration up to 400K rad/sec2. The motors are well-suited for applications where rapid changes in rotation are required (±3,000 RPM in a few ms) including electronic yarn guides, medical XY tables, and robotics. (Source: Portescap)
Good article, but I think the editor missed something. Units for torque aren't millimeters! Millimeters (mm) are a distance unit, torque is a force (F) vector multiplied by a distance vector (r) to yield the cross-product torque vector (T=F x r). the correct units are Newton-millimeters (N-mm), dyne-centimeters (dyne-cm), or pound-inches (lbf-in) maybe, but not millimeters (mm).
Interesting article, it is nice to see that changing the shape of the magnet can add a significant increase in the rpm of the motor. With this incredibly large rpm, it can be of great use in robotics and mechatronics applications.
Although, as this large speed is obtained at the cost of torque, and also due to the open loop nature of stepper motor it has to be limited to low torque applications, otherwise faulty conditions will arise. But its a great design acheivement by introducing a disk magnet.
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