Halbach Array Brushless Motor

OSE Brushless Motor

Summary

Due to advances in 3D printing technology, it is now possible to design and print motors. This opens up a new realm of possibility with respect to desktop manufacturing. Open Source Ecology is planning to create a monetary prize for the best 3D printed cordless drill design.

There are, of course, some limitations to 3D-printed artifacts - the plastic may melt or break, does not make an ideal core for a motor and is not easy to mass-manufacture as with traditional factories. Even so, in collaborating around the world, students, teachers, hobbyists and other interested groups may generate an ecology of design and innovation such that over time, these problems are solved. 3D printers may eventually adopt liquid resin printing more widely, print with more robust and/or composite materials and manufacturing techniques may improve such that a quality desktop-manufactured drill becomes a reality.

As a first step in this process, a brushless motor project was taken on by a number of students at London International Academy. The motor build was based on the designs of Christoph Laimer (many thanks for your work!) In particular, we viewed the 3D-Printed Halbach Array Instructable and its associated Youtube Videos. The motor produced by Christoph is of high quality and precision. If this is what you are looking for, we recommend following his instructions and purchasing the stl files for his motor.

The students based their design around the hardware components of the Laimer motor but generated completely new 3D designs in FreeCAD. The motor the students produced is in more of a raw form. There are no threads to attach the rotor cap to the rotor, for example. Even so, the motor seems easily able to exceed 1000rpm (no measurement has yet been made). There are several other design elements that may be improved - in order to get the motor working, for example, two adapter rings had to be printed - the "Motor Ring" and the "Bearing Adapter Ring." These may be incorporated into future modifications and printed as part of other components of the motor.

General Instructions for Motor Assembly

The following CAD files and photos demonstrate that secondary school students are indeed capable of sophisticated design and manufacturing:

CAD Files

CAD files

Photos

photos of the OSE Brushless Motor

Future Work

Based on the result of this project, several avenues of continued development may be taken:

• Explore the advantages and disadvantages of radial and axial designs
• Couple the motor with a gearbox to increase available torque
• Print a second version of the motor with proto-pasta to compare performance
• Design and build an ESC based on the VESC.
• Produce the OSE motor for physics classes - our physics teachers are eager to use the motor in lessons.