PA81-12-18.33 is a Motorevo PA-series integrated planetary joint integrating a brushless motor, planetary reducer, dual encoders and an integrated drive. It delivers 30 Nm rated torque, 90 Nm peak torque and up to 190 rpm, with a total weight of 900 g. It is designed for humanoid robots, quadruped robots and collaborative arms. The standard version does not include a brake. CAN is standard; EtherCAT/CANFD is optional.
105 mmDiameter
53 mmThickness
30 NmRated Torque
90 NmPeak Torque
190 rpmPeak Speed
900 gWeight
Electrical Specifications
Operating Voltage
48 V
Rated Voltage
12-72 V
Rated Torque
30 Nm
Rated Speed
150 RPM
Rated Current
16 A(rms)
Peak Torque (>3s)
90 Nm
Peak Speed
190 RPM
Peak Current
57 A(rms)
Torque Constant
1.785 Nm/A
Back EMF Constant
- Vrms/Krpm
Speed Constant
71 rpm/V
Motor Constant
- Nm/√W
Mechanical Time Constant
- ms
Electrical Time Constant
- ms
Pole Pairs
14
Winding Connection
Star (Y)
Phase Resistance
0.282 Ω
Phase Inductance
0.217 mH
Mechanical Specifications
Diameter
105 mm
Thickness
53 mm
Weight
900 g
Gear Ratio
18.33
Backlash
10 Arcmin
Output Bearing
Crossed roller bearing
Backdrive Torque
1 Nm
Rotor Inertia
- g·cm²
Axial Load
10.6 kN
Radial Load
4.7 kN
Control & Communication
Control Bandwidth
2000 Hz
Communication
CAN (EtherCAT/CANFD optional)
Encoder Type
Mechanical dual encoder
Encoder Resolution
14 bit
CAN Interface
XT30(2+2)PW-M
USB Interface
SH1.0-4P
Power Interface
XT30(2+2)PW-M
Control Modes
Servo Mode
✓
Velocity Mode
✓
Torque Mode
✓
Hybrid Force-Position Mode
✓
Protection
Overvoltage Protection
✓
Overcurrent Protection
✓
Overtemperature Protection
✓
Environment & Reliability
Duty Cycle
S2 (short-time duty)
Ingress Protection
IP40 (standard; IP54 optional on request)
Cooling Method
IC410 (self-cooled)
Operating Temperature
-20°C to 50°C
Insulation Class
F
Dielectric Strength
500V 1kHz 1A 1ms
Insulation Resistance
100 MΩ @ 20°C
Temperature Sensor
NTC MF52B 103F3950
Noise
60 dB / 0.5 m
Loading 3D teardown…
The 3D teardown is generated from this model’s diameter, thickness, gear ratio and hollow bore. Orbit, explode and inspect 15 components.
