Electromate Expands Mobile Robotics Offering with maxon HEJ 90 High-Efficiency Joint
January 26, 2026
Newly Available maxon HEJ 90 High-Efficiency Joint Delivers High Torque Density & Energy Efficiency for Battery-Powered Robots
Electromate has announced the availability of the maxon HEJ 90 High-Efficiency Joint, a compact, integrated actuator designed for high-torque joints in mobile and legged robotic systems.
The HEJ 90 combines a brushless motor, precision gearbox, encoder, servo drive, and thermal monitoring into a sealed joint assembly, reducing system complexity while delivering high torque density and energy efficiency for battery-powered robots.
The HEJ 90 delivers up to 140 Nm of peak torque, with configurable options extending to 180 Nm peak torque, while supporting joint speeds up to 13 rad/s. With efficiencies reaching 86 percent, the joint minimizes power losses and heat generation, extending the operating time of autonomous mobile platforms.
The joint’s compact footprint (110 mm diameter, 90 mm length) and mass of approximately 1.96 kg make it suitable for space-constrained designs such as quadruped robots, humanoid joints, mobile manipulators, and propulsion or steering joints in wheeled and tracked robots.
Integrated Architecture Simplifies System Design
By integrating motor control electronics directly into the joint, the HEJ 90 eliminates the need for external servo drives and reduces wiring and cabinet space. The joint supports EtherCAT communication with real-time control at up to 1 kHz, enabling precise torque, velocity, and position control.
Dual EtherCAT ports support daisy-chain configurations, simplifying multi-axis robot architectures. Absolute position feedback and low-backlash mechanical design support accurate motion control and force-based interaction in dynamic environments.
Built for Real-World Operating Conditions
The HEJ 90 is rated IP67, allowing operation in dusty, wet, and outdoor environments commonly encountered in mobile robotics. Integrated thermal monitoring and optional active cooling support sustained operation under high loads and demanding duty cycles.
The HEJ 90 High-Efficiency Joint is now available through Electromate. Configuration support, technical documentation, and application guidance are provided for OEMs and system integrators developing mobile robotic platforms.
Specifications
| Parameter | HEJ 90‑48‑140 |
|---|---|
| Peak Torque | 140 Nm (up to 180 Nm custom) |
| Max Joint Speed | 13 rad/s |
| Dimensions (Ø × L) | 110 mm × 90 mm |
| Mass | 1.96 kg |
| Efficiency | Up to 86 % |
| Ingress Protection | IP67 (sealed under bending loads) |
| Voltage Range | 30–60 V DC |
| Control Interface | Dual EtherCAT, 1 kHz control, torque/velocity/position/impedance modes |
| Position Encoder | Absolute, integrated |
| Output Bearing | Cross-roller bearing |
For more information on Electromate solutions HERE
maxon HEJ 90 maxon HEJ 90
