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QDD Motors logoQDD Motors

Industrial motion manufacturer supporting custom engineering, strict quality control, and global delivery.

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© 2026 QDD Motors. All Rights Reserved.|QDD Motors supports OEM robot joint motor programs with engineering review, manufacturing coordination, quality records, and export delivery planning.
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Low Ratio Geared Motors

Low-ratio planetary geared motor assemblies for backdrivable robot joints, responsive torque control, and compact OEM drive modules.

Target Buyer:Best for robotics buyers comparing harmonic drives, direct drive, and quasi-direct drive architectures by compliance, shock tolerance, and cost.

Inquiry Email

[email protected]

Email app

Include target torque/speed, quantity, and delivery location.

Instant Chat

+86 188 5797 1991

Request CAD Model via WhatsApp

Opens a direct WhatsApp thread with the RFQ message prefilled.

Low ratio geared motor for backdrivable robot joints

Capability Highlights

  • 6:1, 8:1, 10:1, and custom low-ratio options
  • Planetary gearsets optimized for backdrivability
  • Low backlash and controlled reflected inertia

Typical Applications

  • QDD actuator reduction stages
  • Robot dog leg joints
  • Force-control educational robots
  • Compact mobile robot drive modules

Engineering Focus

  • Gear ratio selection against reflected inertia
  • Backlash, efficiency, and shock-load margin
  • Lubrication, noise, and wear targets
  • Motor-reducer-driver co-validation

Key Evaluation Matrix

MetricTypical RangeWhy It Matters
Gear Ratio6:1 - 12:1 typical, custom availableKeeps reflected inertia low enough for compliant force control and impact recovery.
Backdrive TorqueApplication tunedDetermines whether the joint feels transparent enough for legged robots and human-assist devices.
BacklashLow backlash design targetsMaintains controllability in position, velocity, and torque loops.

RFQ Checklist

  1. Define target ratio and allowable backlash
  2. Share output torque, shock load, and speed profile
  3. Confirm motor frame, shaft, and mounting interface
  4. State backdrive torque or force-control requirement
  5. Provide noise, lifetime, and lubrication constraints

Risk Controls

  • Using too high a ratio: Compare direct drive, QDD, and harmonic-drive options against reflected inertia and backdrive needs.
  • Gear wear under shock loads: Validate shock torque, lubrication, material treatment, and test duty cycle before pilot order.
  • Noise and backlash drift: Set incoming, EOL, and life-test checks for backlash, NVH, and efficiency.

Product Gallery

Precision low backlash reducer for actuator assemblies
Precision low backlash reducer for actuator assemblies
Planetary gearbox for low ratio geared motor integration
Planetary gearbox for low ratio geared motor integration

Buyer FAQ

Why choose a low-ratio gearbox for robot joints?

Low ratios preserve backdrivability and reduce reflected inertia while still multiplying torque enough for compact robot joints.

Can you pair the gearbox with a custom BLDC motor?

Yes. We can co-design the motor winding, reducer ratio, encoder, and driver limits as an actuator system.

Related Resources

  • QDD Actuators
  • High Torque BLDC Motors
  • Quadruped & Humanoid Joints
  • Start RFQ

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