Leadshine HJ2 Harmonic Joint Module Series
Vendor: 雷赛智能 Leadshine (China)
Product: HJ2 系列谐波关节模组

The HJ2 series from Shanghai Leadshine Robotics is a harmonic joint module family for humanoid robots with integrated motor, driver and encoder, a unified 101 reduction ratio and five frame sizes (52-110): 11-194 N·m start/stop peak torque and 8.9-133 N·m average load torque; the in-house FM2 frameless torque motor cuts heat by 25%, a 24-bit encoder and EtherCAT bus enable precise control, and the design is 65% lighter and 20% smaller for humanoid limbs, waist and neck joints.
| motor | FM2 frameless torque motor |
| design | integrated motor+driver+encoder, 65% lighter, 20% smaller |
| encoder | 24-bit |
| protocol | EtherCAT |
| variants | HJ2-52 / HJ2-70 / HJ2-80 / HJ2-90 / HJ2-110 |
| peak_torque | 11 / 34 / 66 / 102 / 194 N·m |
| rated_speed | 37 / 52 / 37 / 36 / 31 rpm |
| avg_load_torque | 8.9 / 13.5 / 49 / 61 / 133 N·m |
| reduction_ratio | 101 |
| rated_torque_2000rpm | 5 / 9.6 / 30 / 50 / 84 N·m |