Check peak load first
Compare the joint moment from your intended trajectory with a supplier torque-speed curve at the same speed and bus voltage.
105 Nm robotic actuator module
105 Nm robotic actuator module: screen a QDD joint target
Estimate a static-equivalent joint moment from per-joint load assumptions, then compare it with the 105 Nm page target. This screen does not select or certify an actuator.
Target class only · request a signed model datasheet
Request verified torque dataScreening result
58.9 Nm
Example valuesBelow the 105 Nm page target in this simplified estimate. This does not establish actuator suitability.
Estimated moment vs 105 Nm page target56% of target
46.1 Nm below the page target
The comparison uses a 105 Nm page target, not a verified continuous or peak rating for a specific model. Confirm torque duration, speed, thermal duty, and current limit with the supplier.
Three decisions to make before choosing a 105 Nm module
Then check heat over time
Peak torque alone does not establish continuous capability. Ask for the duty cycle, test ambient, mounting fixture, and temperature limits behind the continuous rating.
Confirm the package
Verify mass, dimensions, bearings, sensors, bus protocol, and connector pinout against the robot interface before procurement.
Method and evidence
A transparent static-equivalent moment estimate
The calculator uses effective mass at one joint, gravity, a perpendicular moment arm, and your selected multiplier. It is a screening calculation; it does not solve robot kinematics or dynamics, estimate motor current, or validate thermal performance.
M = m × 9.81 × r × k
- m
- effective mass carried by this joint, kg
- r
- perpendicular moment arm, m
- k
- user-selected load multiplier
Use it for
Early shortlist discussions when a per-joint effective mass, lever arm, and load multiplier are available.
Do not use it for
Final actuator selection, safety approval, gait prediction, jump landing analysis, continuous torque sizing, or gearbox life approval. Use multibody simulation and measured data for those decisions.
What is known on this page and what needs supplier confirmation
The page identifies a 105 Nm target class. It does not include a revision-controlled datasheet for a specific orderable configuration.
| Decision item | Published here | Confirm before design freeze |
|---|---|---|
| Torque class | 105 Nm target class | Peak torque definition, speed, current, and pulse duration |
| Thermal envelope | Not specified | Continuous torque, duty cycle, ambient, mounting, and temperature limit |
| Mechanical package | Illustrative image only | Mass, envelope drawing, shaft/flange, bearings, and allowable loads |
| Electrical and control | Not specified | Voltage range, current limits, speed curve, encoder, bus, firmware, and connectors |
| Life and environment | Not specified | Gear life evidence, shock limits, ingress rating, lubrication, and operating temperature |
Compare transmission approaches against the joint job
These are qualitative design prompts. Actual friction, stiffness, backlash, efficiency, and impact limits depend on the chosen hardware and test conditions.
| Approach | Potential fit | Ask / validate |
|---|---|---|
| Low-ratio QDD | Dynamic joints where force interaction and backdrivability matter | Backdrive torque, reduction, motor limits, heat path, and peak duty |
| High-ratio geared joint | Applications prioritizing compact torque multiplication or position holding | Friction, output stiffness, backlash, impact load, and service life |
| Series-elastic joint | Applications that can use intentional compliance for force interaction | Spring travel, resonance, bandwidth, packaging, and fatigue life |
Three assumptions, three different screening outcomes
The examples below are arithmetic demonstrations of the stated formula, not measured robot cases or validated product matches.
Light link example
8 kg · 0.20 m · 1.5×
23.5 Nm
Below the page target in this simplified screen.
Default example
12 kg · 0.25 m · 2.0×
58.9 Nm
Requires trajectory and thermal checks.
Higher load example
20 kg · 0.30 m · 2.5×
147.2 Nm
Above the page target; review mechanism and actuator class.
Resolve these risks before committing the joint design
Torque and thermal
A moment estimate cannot establish continuous operation. Request peak and continuous torque-speed curves plus thermal test setup, duty cycle, and derating rules.
Mechanical fit and life
Side loads, shocks, bearing span, mounting stiffness, and service conditions affect the gear train. Request drawings, allowable loads, and life or endurance evidence for the intended spectrum.
Control and sensing
Encoder placement and motor-current torque estimates do not by themselves establish output accuracy or a safety-rated function. Define the required torque feedback and fault response.
Procurement and cost
Custom windings, housings, sensors, and connectors can change price, schedule, qualification effort, and future interchangeability. Get the quoted configuration and change-control terms in writing.
Questions to settle during actuator selection
Is 105 Nm the continuous rating?
This page does not establish whether 105 Nm is a peak, stall, or continuous rating, nor its duration or speed. Request the configuration-specific torque-speed and thermal data.
Can this calculator select a motor?
No. It estimates a simplified joint moment. Final selection also needs trajectory torque and speed, RMS duty, electrical limits, mechanical loads, and thermal validation.
What does effective mass mean?
It is the mass whose weight creates the modeled moment at this joint. Estimate it from the joint load case; robot total mass is not automatically the value for one actuator.
Does the multiplier model a landing?
It only scales the static-equivalent moment. It does not predict landing force, impact duration, contact geometry, or gearbox shock load. Use simulation or measurement for those cases.
What is included in the module?
The public page does not confirm the bill of materials for a specific configuration. Ask whether the quote includes motor, reducer, sensors, drive electronics, cables, and firmware.
What should an RFQ include?
Share the joint load and speed profile, duty cycle, environment, mechanical envelope, bus and sensing requirements, quantities, and validation needs. Request a revision-controlled response.
Next step
Request the data needed for an engineering decision
Send the application and load profile with your RFQ. Ask the supplier to identify which quoted configuration each drawing, curve, and test result covers.
- Peak and continuous torque-speed curves
- Torque peak duration and current limits
- Thermal test conditions and derating data
- CAD, mass, mounting, and allowable loads
- Encoder, bus, connector, and firmware details
- Life, shock, environmental, and quality evidence
Contact engineering
Inquiry Email
Include robot type, joint location, torque/speed/voltage targets, quantity, and destination.
Instant Chat
+86 18857971991
Send QDD actuator specs, STEP files, or actuator references for engineering review.
Evidence and limitations
The formula above is shown explicitly so the estimate can be reproduced. The research reference below supports the general design trade-off for dynamic legged robots; it does not validate this page's 105 Nm target or any specific supplier configuration.
Wensing et al., IEEE Transactions on Robotics, 2017. The study discusses high-bandwidth force interaction and impact mitigation in its tested legged-robot system. Its results are architecture evidence, not a specification for this module.
Page and source reviewed September 30, 2026. Product-specific public datasheet: not linked on this page; request the signed revision and supporting test reports from the supplier.