Engineering Resources

Inverted Roller Screw Engineering Hub

Access the technical data needed to achieve Spec Lock on your actuator project.

We provide comprehensive engineering support from the concept phase through mass production. Below you can request our 3D CAD libraries, sizing guidelines, and detailed product catalogs to accelerate your design cycle.

3D CAD Models

Request STEP and IGES files for standard and inverted planetary roller screws to import directly into SolidWorks, NX, or AutoCAD.

Request CAD

Product Catalogs

Detailed technical specifications, load ratings, inertia values, and dimension tables for our complete linear motion lineup.

Request Catalog

Design Guides

Whitepapers and technical notes covering lubrication selection, critical speed calculation, and column buckling analysis.

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Humanoid Joint: Sizing & Lead Calculator

Estimate the required Static Load Rating (C0) and optimal thread lead for bipedal robotic joints based on impact dynamics.

Robot Total Mass60 kg

Typical biped ranges from 30kg to 100kg.

Peak Impact Multiplier (Heel Strike)4x

Running or jumping incurs 4x to 8x body weight forces.

Peak Joint Force (Transient)

2,354 N

Target Static Load Rating (C0)

3,531 N

Includes 1.5x structural safety factor.

Recommended Thread Lead

4-5mm

Balances back-drivability (impedance control) with motor holding torque.

Engineering Note: This is a simplified 1D linear approximation for knee joints. Actual hip/ankle kinematics require resolving the lever arm ratio. Take these C0 targets to our DFM engineers for exact inverted roller screw selection.

Architecture Selection Logic

Start with the actuator problem, not the product name. The table below helps engineering and procurement teams decide which path deserves a detailed DFM review.

Design Constraint	Recommended Path	Validate First	Common Mistake
Short axial envelope, motor integrated around screw	Inverted planetary roller screw	Nut length, bearing span, rotor interface, heat path, and preload target.	Comparing screw length without including bearings, encoder, seals, and push-tube interfaces.
High-force open-axis or electric-cylinder layout	Standard planetary roller screw	Equivalent mean load, speed, stroke, lubrication interval, and mounting stiffness.	Selecting from peak thrust alone and ignoring duty cycle or thermal limits.
Robotic finger, gripper, or medical micro package	Micro inverted roller screw	OD, stroke, torque, noise, cleanliness, corrosion, and assembly handling.	Treating a miniature screw as a scaled-down industrial screw without validating friction torque.
Proprietary geometry or unavailable catalog size	Custom roller screw manufacturing	Drawing revision, CTQ list, material, heat treatment, inspection scope, and sample acceptance criteria.	Asking for price before freezing the drawing baseline and required release documents.

Specification Inputs for a Useful DFM Review

Input	What to Send	Engineering Decision
Architecture and envelope	Inverted, standard planetary, micro, or actuator screw set; OD, stroke, total length, nut length, and shaft ends.	Confirms whether compact RVI, standard RV, or a custom set is the right route.
Load and motion profile	Peak/static/dynamic force, speed, acceleration, duty cycle, life expectation, and shock-load assumptions.	Drives lead, diameter, preload, material, and lubricant choices.
Precision target	Backlash or preload target, stiffness, positioning accuracy, repeatability, lead class, and torque limits.	Defines inspection method and sample acceptance evidence.
Program context	Drawing/STEP/sample status, prototype or batch quantity, destination, delivery target, and document requirements.	Aligns quote, lead time, and export documentation with the buyer approval process.

Parameter Meaning for Roller Screw RFQs

Parameter	What It Controls	Useful Buyer Input	Output to Expect
Lead	Speed, motor torque, thrust, back-drivability, and holding behavior.	Desired speed, force target, motor torque limit, and force-control need.	Lead recommendation with trade-offs, not only a catalog pitch.
Preload / backlash	Reversal behavior, stiffness, positioning repeatability, friction, heat, and service life.	Allowable axial play, reversal test method, stiffness goal, and torque limit.	Sample acceptance target and measurement method.
Dynamic/static load	Screw size, fatigue life, shock margin, material, and heat treatment.	Peak force, equivalent mean load, speed, duty cycle, shock factor, and life target.	Load/life review and risk notes for oversizing or undersizing.
Material and coating	Hardness, corrosion, wear, distortion risk, cleanliness, and compliance documents.	Alloy preference, environment, lubricant, coating restrictions, and traceability needs.	Material route, heat-treatment notes, and document package scope.

What an Engineering Review Should Return

Architecture notes

Inverted, standard planetary, micro, or custom component path with the main packaging trade-offs stated clearly.

Manufacturing risks

Long nut grinding, heat-treatment distortion, preload, lubrication, inspection access, and assembly concerns.

Sample release plan

CTQ dimensions, pass/fail checks, document package, delivery assumptions, and open items before prototype PO.

RFQ Checklist for Actuator Design

To ensure a rapid and accurate Design for Manufacturability (DFM) review, please prepare the following information before contacting our team:

Application Type: Humanoid robotics, aerospace, heavy machinery, etc.
Envelope Constraints: Maximum allowable outer diameter and overall length.
Performance Targets: Peak dynamic load, continuous thrust, max linear speed, and duty cycle.
Precision Requirements: Required backlash (or zero backlash), positioning accuracy, and repeatability.
Environment: Temperature range, contamination exposure, and lubrication preferences.

Start From the Closest Product Path

Inverted Planetary Roller Screw for compact RVI architecture and long nut packaging.
Inverted Roller Screw Actuator for frameless motor, housing, and push-tube integration reviews.
Micro Inverted Roller Screw for robotic finger, gripper, medical, and compact mechanism programs.
Internal Thread Grinding when the long internally threaded nut is the project bottleneck.

Inquiry Email

[email protected]

Email app

Include target OD, lead, stroke, load, quantity, and delivery country.

WhatsApp Engineering

+8618857971991

Chat on WhatsApp

Best for quick RFQ clarification and drawing-review coordination.

Architecture Selection Logic

Start with the actuator problem, not the product name. The table below helps engineering and procurement teams decide which path deserves a detailed DFM review.

Design Constraint	Recommended Path	Validate First	Common Mistake
Short axial envelope, motor integrated around screw	Inverted planetary roller screw	Nut length, bearing span, rotor interface, heat path, and preload target.	Comparing screw length without including bearings, encoder, seals, and push-tube interfaces.
High-force open-axis or electric-cylinder layout	Standard planetary roller screw	Equivalent mean load, speed, stroke, lubrication interval, and mounting stiffness.	Selecting from peak thrust alone and ignoring duty cycle or thermal limits.
Robotic finger, gripper, or medical micro package	Micro inverted roller screw	OD, stroke, torque, noise, cleanliness, corrosion, and assembly handling.	Treating a miniature screw as a scaled-down industrial screw without validating friction torque.
Proprietary geometry or unavailable catalog size	Custom roller screw manufacturing	Drawing revision, CTQ list, material, heat treatment, inspection scope, and sample acceptance criteria.	Asking for price before freezing the drawing baseline and required release documents.

Specification Inputs for a Useful DFM Review

Input	What to Send	Engineering Decision
Architecture and envelope	Inverted, standard planetary, micro, or actuator screw set; OD, stroke, total length, nut length, and shaft ends.	Confirms whether compact RVI, standard RV, or a custom set is the right route.
Load and motion profile	Peak/static/dynamic force, speed, acceleration, duty cycle, life expectation, and shock-load assumptions.	Drives lead, diameter, preload, material, and lubricant choices.
Precision target	Backlash or preload target, stiffness, positioning accuracy, repeatability, lead class, and torque limits.	Defines inspection method and sample acceptance evidence.
Program context	Drawing/STEP/sample status, prototype or batch quantity, destination, delivery target, and document requirements.	Aligns quote, lead time, and export documentation with the buyer approval process.

Parameter Meaning for Roller Screw RFQs

Parameter	What It Controls	Useful Buyer Input	Output to Expect
Lead	Speed, motor torque, thrust, back-drivability, and holding behavior.	Desired speed, force target, motor torque limit, and force-control need.	Lead recommendation with trade-offs, not only a catalog pitch.
Preload / backlash	Reversal behavior, stiffness, positioning repeatability, friction, heat, and service life.	Allowable axial play, reversal test method, stiffness goal, and torque limit.	Sample acceptance target and measurement method.
Dynamic/static load	Screw size, fatigue life, shock margin, material, and heat treatment.	Peak force, equivalent mean load, speed, duty cycle, shock factor, and life target.	Load/life review and risk notes for oversizing or undersizing.
Material and coating	Hardness, corrosion, wear, distortion risk, cleanliness, and compliance documents.	Alloy preference, environment, lubricant, coating restrictions, and traceability needs.	Material route, heat-treatment notes, and document package scope.

What an Engineering Review Should Return

Architecture notes

Inverted, standard planetary, micro, or custom component path with the main packaging trade-offs stated clearly.

Manufacturing risks

Long nut grinding, heat-treatment distortion, preload, lubrication, inspection access, and assembly concerns.

Sample release plan

CTQ dimensions, pass/fail checks, document package, delivery assumptions, and open items before prototype PO.

RFQ Checklist for Actuator Design

To ensure a rapid and accurate Design for Manufacturability (DFM) review, please prepare the following information before contacting our team:

Application Type: Humanoid robotics, aerospace, heavy machinery, etc.

Envelope Constraints: Maximum allowable outer diameter and overall length.

Performance Targets: Peak dynamic load, continuous thrust, max linear speed, and duty cycle.

Precision Requirements: Required backlash (or zero backlash), positioning accuracy, and repeatability.

Environment: Temperature range, contamination exposure, and lubrication preferences.

Start From the Closest Product Path

Inverted Planetary Roller Screw for compact RVI architecture and long nut packaging.

Inverted Roller Screw Actuator for frameless motor, housing, and push-tube integration reviews.

Micro Inverted Roller Screw for robotic finger, gripper, medical, and compact mechanism programs.

Internal Thread Grinding when the long internally threaded nut is the project bottleneck.