Who should use this
Robotic arm, cobot, humanoid and EOAT teams selecting strain wave or harmonic gearbox options for compact joints.
Resources
Motion, Drive & Actuation
Harmonic Gearbox Selection Guide
Prepare ratio, backlash, torque, speed, flange, mounting, lubrication and lifetime inputs for robot joint reducer sourcing.
Hardware decision
The guide helps align torque rating, ratio, backlash and mounting interface before requesting gearbox quotes, drawings or STEP/STP files.
Prepare before RFQ
Bring reduction ratio, backlash, torsional stiffness, rated and peak torque, input speed, output flange, mounting interface, lifetime, lubrication, sealing, motor, encoder, brake and inertia-matching context.
When to use this guide
Start here if the hardware question affects sourcing, files or RFQ review.
- A robot joint needs compact reduction and the final ratio or torque margin is not yet fixed.
- The CAD envelope, mounting interface or output flange affects sourcing.
- You need drawings or STEP/STP files for fit review without treating supplier source files as public downloads.
Key engineering decisions
Ratio and backlash
State target ratio, positioning tolerance, expected backlash limit and whether the joint is force, position or speed sensitive.
Torque, speed and inertia margin
Motor inertia, reducer ratio and load inertia should be reviewed together when the reducer is used in humanoid limbs, robotic arms or high-dynamic axes.
Mounting interface
Record output flange, bolt pattern, pilot diameter, motor adapter and available joint envelope.
Life and environment
Capture duty cycle, lubrication, sealing, vibration and operating environment before asking for lifetime notes.
RFQ preparation checklist
Include these inputs before asking for quote or document review.
- Target ratio
- Backlash and torsional stiffness expectation
- Rated and peak torque
- Input speed
- Output flange and mounting interface
- Lifetime, lubrication and sealing
- Motor, encoder, brake and inertia context
- Required datasheet, 2D drawing or STEP/STP file
Engineering file considerations
Document access depends on file type and review context.
- Public pages can show selection ranges and preview data.
- Original STEP/STP, full dimensioned drawings and supplier-sensitive records may require controlled access review.
- Lifetime notes support engineering review but do not replace customer validation.
Related guides
Related product categories
Related custom builds
Related integration packages
Related applications
Not covered by this guide
Axis dynamics certification
Lifetime testing certification
Final robot joint validation
Overload or shock failure guarantee
Ready to attach this guide to a real request?
Use the guide checklist to submit one RFQ with product, file and subsystem context. Controlled access may apply to STEP/STP, native CAD, full drawings and supplier-sensitive records.