frameless motor stator

Custom Frameless Motor with Stator & Rotor Options

Frameless Motors Built to Your Requirements

A customer who has an extensive mechatronic assembly requirement that includes an electric motor may not need a fully housed motor. Our team will design and manufacture Frameless Motors that meet high torque capabilities, high conductor fill factor, and specific electrical footprints tailored to meet your objectives.

Frameless Motors of a fundamental element of today’s mechatronic systems and include both Stator and Rotor as separate components. US Motion engineers are capable of designing and fabricating many types of Frameless Motors and offer expert advice for your custom application need.

STATOR options include:

stator motor

  • Slotted or slotless construction
  • Welded or bonded laminations
  • Powder coated or Nomex stator insulation
  • Skewed or straight
  • Conventional wound conductor or multilayer PCB stators
  • Contact US Motion to ask about additional options

ROTOR options include:

frameless motor

  • Surface Permanent Magnet (SPM) and Internal Permanent Magnet (IPM) Rotors
  • Various Permanent Magnet materials and grades: Neodymiium, Samarium Cobalt, Alnico, and others
  • Skewed or Straight Magnets
  • Non-Permanent Magnet type: Squirrel Cage/Induction or Switched Reluctance
  • Laminated or Solid Core
  • Radial Flux or Axial


Through focused electromagnetic design theory, proven manufacturing methods, theoretical and practical applications, and exploratory technology, US Motion gives their customers a comprehensive proposition for their Frameless Motor needs.

Our team is proficient in:

  • Frameless motor system integration
  • Manufacturing tolerances: dimensional and magnetic and the effect on motor performance, e.g. cogging torque
  • Designing for low sensitivity to manufacturing imperfections
  • Cogging torque theory, measurement, and minimization or maximization
  • Motor sizing, based on your application
  • Thermal modeling leading to thermal validation, e.g. temperature effects on magnetic performance
  • Reversible and irreversible magnetization processes
  • Iterative design and optimization based on finite element methods
  • Quality testing standards required for various specialty applications (vacuum, spaceflight and temperature extremes

We will work with you to design the best Frameless Motor adapted to your needs and application use! Contact US Motion