Skip to content

Integrated robot joint actuator

CubeMars AK Series integrated robot joint actuator

Planetary-geared robot joint actuators with built-in driver and magnetic encoders, from the 190 g AK40-10 to the AK80-64 (series maximum 120 Nm peak); the AK10-9 V3.0 gives 18 Nm rated and 53 Nm peak at 48 V.

Key specifications

Voltage (max)48 V
Data / busCAN, UART
Rated torque (max)48 Nm
Peak torque (max)120 Nm
Speed (max)800 rpm
Supply24/48 V
Ratio9–64:1
Backlash (max)10.8 arcmin
Weight185–960
Controlservo and MIT modes
Encodermagnetic, up to 21-bit inner / 15-bit outer (AK10-9 V3.0)

Summarised in our own words from Nanchang Kude Intelligent Technology Co., Ltd. (wholly owned subsidiary of Nanchang Sanrui Intelligent Technology Co., Ltd.)'s published data; series maxima, individual models vary. Last checked 2026-10-30. Source 1 · Source 2 · Source 3

Notes on this data

Ratios confirmed only for AK10-9 (9:1) and AK80-64 (64:1); other model suffixes appear to indicate ratio but are not stated.

Specify Motion is not affiliated with Nanchang Kude Intelligent Technology Co., Ltd. (wholly owned subsidiary of Nanchang Sanrui Intelligent Technology Co., Ltd.). CubeMars and AK Series are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.

Typical applications

Legged robotsExoskeletonsAGVsCollaborative robot arms

Alternatives that meet or exceed these figures

Engineers often come to us with a CubeMars part number and leave with an alternative that is easier to source, quicker to deliver or a better fit for the machine. These 3 series from our supply network are the closest match on published figures.

Planetary gearbox

Wanshsin WSH

Meets or exceeds on all 3 published figures compared

High-rigidity Wanshsin inline planetary with three backlash classes down to super-precision, for machine tools, automation and AGVs.

Published maximumAK SeriesWSH
Peak torque120 Nm7,200 Nm meets or exceeds
Rated torque48 Nm2,400 Nm meets or exceeds
Speed800 rpm6,000 rpm meets or exceeds
View WSH →
Spiral bevel gearbox

Wanshsin WSHR

Meets or exceeds on all 3 published figures compared

Right-angle version of the high-rigidity WSH, with a spiral bevel stage and ratios up to 200:1.

Published maximumAK SeriesWSHR
Peak torque120 Nm4,200 Nm meets or exceeds
Rated torque48 Nm1,400 Nm meets or exceeds
Speed800 rpm6,000 rpm meets or exceeds
View WSHR →
Planetary gearbox

Wanshsin WTH

Meets or exceeds on all 3 published figures compared

Wanshsin inline planetary designed for high radial loads, offered in three precision classes.

Published maximumAK SeriesWTH
Peak torque120 Nm6,150 Nm meets or exceeds
Rated torque48 Nm2,050 Nm meets or exceeds
Speed800 rpm6,000 rpm meets or exceeds
View WTH →

Figures are the highest published for each series and are not always measured the same way. A higher figure is not automatically a better choice: mounting, duty cycle, feedback, connectors and approvals matter too. An engineer will check the fit against your application before recommending anything.

What an integrated robot joint actuator is

An integrated robot joint actuator packages a brushless motor, a reduction gear, encoders, a servo drive and often a brake or torque sensor into one module that bolts in as a robot joint. Gearing may be planetary, strain-wave or cycloidal. Many are designed for legged robots, humanoids and cobots, with low gear ratios or quasi-direct drive to keep the joint back-drivable and responsive. Communication is typically over CAN or EtherCAT, with position, velocity and torque control modes.

When engineers choose an integrated robot joint actuator

Choose an integrated joint actuator to build robots faster with fewer parts, especially legged, humanoid, exoskeleton and collaborative robots. Back-drivable versions suit force control and impacts. The trade-offs are torque density, precision and industrial qualification: low-ratio designs trade output torque for transparency, and some units are aimed at research rather than production duty. For industrial arms with heavy duty cycles, a dedicated harmonic actuator or motor and gear set may be better.

How to specify the CubeMars AK Series

Send these with your enquiry and an engineer can confirm the right AK Series variant or an equivalent:

  • Peak and continuous output torque (Nm)
  • Output speed (rpm)
  • Gear type and ratio
  • Back-drivability and torque sensing
  • Supply voltage (V DC)
  • Communication interface and control modes
  • Mass and size (kg, mm)

Common mistakes to avoid

  • Using peak torque as continuous torque
  • Ignoring thermal limits in legged robots
  • Overlooking bus bandwidth with many joints
  • Assuming research-grade units meet industrial life requirements

CubeMars AK Series: frequently asked questions

What is the CubeMars AK Series?

Planetary-geared robot joint actuators with built-in driver and magnetic encoders, from the 190 g AK40-10 to the AK80-64 (series maximum 120 Nm peak); the AK10-9 V3.0 gives 18 Nm rated and 53 Nm peak at 48 V. Published series figures include voltage 48 V, rated torque 48 Nm, peak torque 120 Nm, speed 800 rpm. It is made by Nanchang Kude Intelligent Technology Co., Ltd. (wholly owned subsidiary of Nanchang Sanrui Intelligent Technology Co., Ltd.); Specify Motion can help source it or propose an equivalent.

Who makes the CubeMars AK Series?

The CubeMars AK Series is made by CubeMars (Nanchang Kude Intelligent Technology Co., Ltd. (wholly owned subsidiary of Nanchang Sanrui Intelligent Technology Co., Ltd.)) and is listed here for engineers comparing options. Specify Motion is not affiliated with Nanchang Kude Intelligent Technology Co., Ltd. (wholly owned subsidiary of Nanchang Sanrui Intelligent Technology Co., Ltd.); brand names are used only to identify the product.

What is the voltage of the CubeMars AK Series?

The published series maximum voltage is 48 V. Individual models and sizes in the AK Series range vary, so check the exact variant against your duty cycle, mounting and environment, or ask our engineers to confirm the right size for you.

Is there an alternative to the CubeMars AK Series?

Yes. On published figures, Wanshsin WSH and Wanshsin WSHR are the closest match from our supply network. An engineer confirms the fit against your application before recommending anything.

What is a quasi-direct-drive actuator?

A quasi-direct-drive actuator uses a high-torque motor with a low gear ratio, typically below about 10:1, so the joint is back-drivable and responds quickly to external forces. This suits legged robots and force control. The trade-off is lower output torque than high-ratio joints of similar size.

Why integrate the drive in a robot joint actuator?

Integrating the drive reduces cabling and lets each joint communicate over a shared bus, which simplifies robot design. It also allows the drive to sit close to the motor, improving control. The trade-off is that heat from both motor and drive must be managed inside the joint.

Further reading: How to select a harmonic actuator · Frameless motor sizing robot joints · Gearboxes and harmonic drives

Other integrated robot joint actuator series

Spec builder

Specify what you need instead of AK Series

Select every part you need, answer the questions an applications engineer would ask, and see your summary before we ask for any details.

  1. 1Products
  2. 2Performance
  3. 3Environment
  4. 4Volumes
  5. 5Your spec
Step 1 of 5

Engineer support

Let our experienced engineers do the hard work for you

Tell us how you use the CubeMars AK Series: the load, speed, duty and environment. Our engineers will confirm whether it is still the right part, find it for you, or propose an alternative that fits better.

  • Reviewed by an engineer, not an autoresponder
  • Like-for-like and better-fit alternatives
  • Standard, modified and custom options

Prefer to configure it? Use the spec builder.

We use your details to answer this enquiry and share them with the specialist engineering and supply partner best placed to fulfil it. See our privacy notice.