CRA-RI50-60-PRO-S Integrated Robot Joint Actuator, 51/81/101:1, 23–34 N·m Peak, Hollow-shaft, 24–48 V, CAN, 17-bit

Overview

The CRA-RI50-60-PRO-S-XX is a compact, hollow-shaft integrated robot joint actuator for small/lightweight arms, humanoids, cobots, exoskeletons and UAV mechanisms. It combines a frameless torque motor, precision reducer, dual-encoder feedback and drive electronics in a 60 mm-class module. The PRO-S series emphasizes miniaturization, fast response and a high load-to-weight ratio. This RI50 module offers three reduction options (51/81/101:1) with up to 34 N·m start/stop peak torque and 75 RPM rated output speed (ratio-dependent). A CAN bus interface and 24–48 V input make it easy to integrate into multi-axis systems.

Key Features

• 60 mm-class integrated joint with hollow shaft (through-hole for cables/hoses)

• Reduction ratios: 51:1 / 81:1 / 101:1

• Start/stop peak torque: 23 / 29 / 34 N·m (ratio-dependent)

• Rated speed (at 1/2 rated torque): up to 75 RPM (51:1)

• Backlash: 20 arcsec (51/81:1), 10 arcsec (101:1)

• 24–48 V DC input, 150 W class, CAN communication

• 17-bit encoder feedback, rapid dynamic response

• Two versions: standard and -B with holding brake (larger length/weight, smaller through-hole)

Specifications

Performance by ratio

Electrical & control (common)

• Motor power: 150 W

• Supply voltage: 24–48 V DC

• Max continuous phase current: 5 A

• Rated current: 3.6 A

• Phase resistance: 0.47 Ω

• Torque constant: 0.089 N·m/A

• Inductance: 0.215 mH

• Pole pairs: 10

• Encoder resolution: 17-bit (incremental)

• Bus / Protocol: CAN

Mechanical

Standard (CRA-RI50-60-PRO-S-XX)

• Through-hole: 12 mm

• Length: 60 ± 0.5 mm

• Mass: 0.42 kg

• Rotor inertia: 112 g·cm²

With brake (CRA-RI50-60-PRO-S-XX-B)

• Through-hole: 10 mm

• Length: 82 ± 0.5 mm

• Mass: 0.59 kg

• Rotor inertia: 146 g·cm²

Notes: Dimensions shown are overall module length; brake version adds a holding brake for power-off holding. PRO-S series marketing highlights miniaturization, quick response and sealed construction for dust/water resistance (no specific IP grade stated).

Applications

• 4–7 DOF collaborative and desktop robotic arms

• Humanoid joints (shoulder, elbow, hip, knee, ankle)

• Exoskeleton actuators and rehabilitation robots

• Service/inspection robots, mobile manipulators

• UAV gimbals/mechanisms requiring compact high-torque joints

• Light industrial automation and educational research platforms

Details

CRA-RI50-60-PRO-S-XX robotic actuator with 150W motor, 24-48V supply, CAN communication, and multiple gear ratios. Features include high torque, precise encoder resolution, and compact design for robotics applications.

Crabtree Rio 60 Pro XX Black bike with nS Label and WSS041 at 1LZ Ke4l M257 gear set #45 Mah 4A chain ring #id K1/28r+85e Arcsec with Sprocket S 51 23 8.6 6.6, 97 75 20 81 29 13.5 9.6, 61 46 20 101 34 13.5 9.6, and 49 37 10.

Lightweight joint modules featuring PRO, PRO-S, and NH series with specifications including gear ratios, peak torque, load capacity, rated speed, and torque at 2000 rpm. Models range from CRA-RI30-40 to CRA-RI180-170.