RSF-Supermini Brushless Servo Actuator
Worlds smallest zero backlash servo actuators combining Harmonic Drive precision gears with brushless motor and encoder - small enough to fit inside a robotic finger

RSF-Supermini · 1 product image· Contact LVH for CAD files
Product Overview
The RSF-Supermini series are extremely compact servo actuators using zero backlash Harmonic Drive precision gears with brushless servo motor and incremental encoder. Available in sizes 3C and 5B with gear ratios 30 50 and 100. RSF-5B available with optional brake. Compatible with Mitsubishi MELSERVO-J4. Mass as low as 31g. EN60034-1 and EN60034-5 safety certified.
The RSF-Supermini is a fully integrated rotary actuator combining servo motor, harmonic gear reducer, encoders, servo electronics, and compact mechanical packaging in a single assembly.
Rotary Actuator Architecture
Harmonic Drive rotary actuators integrate a precision strain wave gear with a brushless servo motor in a compact assembly. The hollow shaft design allows cables, pneumatic lines, or laser beams to pass directly through the axis of rotation.
Hollow Shaft Design
Central through-bore enables cable routing through the axis of rotation in robot joint designs.
Zero Backlash Gear
Harmonic Drive strain wave gear provides zero backlash for precise bidirectional positioning.
Brushless Servo Motor
Integrated brushless motor optimised for high cycle duty in automation applications.
High Accuracy
Positioning accuracy better than 1 arc-min with high repeatability across the operating range.
High Torque Density
Compact housing delivers high peak torque relative to size and mass.
Direct Load Attachment
Output flange directly accepts loads without additional coupling or bearing hardware.
Typical Applications
The RSF-Supermini suits robot joint axes, index tables, semiconductor handling, laser beam steering, and precision positioning applications requiring compact hollow shaft actuation with zero backlash.
Key Specifications
Critical performance parameters at a glance
Technical Specifications
Overview
RSF-3C Performance
RSF-5B Performance
Product Attributes
Industrial Applications
These rotary actuators are used in compact motion systems where motor, reducer, and actuator packaging need to be tightly integrated for reliable deployment.
Robot Axis Actuation
Used in robot joints and compact rotary axes where packaged actuation simplifies mechanical and electrical integration.
Automation Modules
Fits automated handling, transfer, and tooling systems requiring a self-contained rotary motion solution.
End-of-Arm Systems
Supports wrist, tool rotation, and other compact axes in end-of-arm and auxiliary robotic mechanisms.
Precision Equipment
Useful in inspection, alignment, and specialist machinery where packaged rotary performance helps reduce integration effort.
OEM Motion Platforms
Helps OEMs build cleaner motion platforms by reducing the number of separate drive-train components.
Mobile & Service Robotics
Supports compact rotary motion subsystems in robots that need efficient packaging and robust mechanical integration.
Factory Modification & Custom Sourcing
This product supports custom configurations and equivalent sourcing
Available Modifications
- •Torque and speed ratio customization
- •Mounting interface modifications
- •Connector and wiring specifications
- •Housing and enclosure options
Sourcing Options
- •Standard product sourcing
- •Equivalent product identification
- •Replacement part sourcing
- •Volume pricing (MOQ may apply)
Request Pricing & Availability
Submit an RFQ for standard products, custom configurations, or equivalent alternatives
Frequently Asked Questions
Technical answers sourced from engineering specifications and integration guides.
The RSF-Supermini series are extremely compact brushless servo actuators with Harmonic Drive gears and incremental encoder. Available in sizes 3C and 5B with mass as low as 31g.
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