Explosion-Proof Robot Joint Solution for Chemical Inspection Quadruped Robots: Planetary Joint Actuator with Up to 500 N·m Peak Torque

In high-risk environments such as petrochemical plants, mining sites, and power facilities, robots are increasingly being used to replace humans in inspection and other hazardous operations. As expectations for these robots evolve from simply “being able to inspect” to “being able to perform practical tasks,” higher requirements are being placed on their core drive components, especially robot joint actuators.

As a professional supplier of core robot drive components, HONPINE has developed and manufactured a series of explosion-proof three-joint modules, including the JRM-E292247-35EN-CG-ACF-S20-Ex, providing robot manufacturers with a highly reliable, production-ready, integrated explosion-proof robot joint solution.

Under high-risk operating conditions, robot motion components face four major challenges: explosion-proof safety, torque performance, temperature control, and mobility over complex terrain. At the same time, they must maintain reliable operation over long periods. HONPINE's series of explosion-proof joint modules are designed around these application requirements to address the challenges of robot operation in hazardous environments.

1. Intrinsically Designed for Explosion Protection

There are currently two main approaches to designing joints for explosion-proof robots.

One approach is to use a standard joint module with an explosion-proof enclosure. This approach can reduce development costs and shorten the development cycle, but the long-term performance of the explosion-proof structure, electrical system, sealing, and thermal management still requires systematic verification.

The other approach is an integrated, explosion-proof design developed from the joint module level, in which the mechanical structure, electrical system, sealing, materials, and thermal management are considered together from the beginning.

In petrochemical and mining environments, flammable gases, dust, and complex operating conditions create additional challenges for explosion-proof robot design. Motors and electrical components inside the joint can become potential ignition sources, while continuous operation can also increase component temperatures. Therefore, adapting a robot joint for explosion-proof applications is not simply a matter of adding an external enclosure. The design needs to address flameproof construction, electrical configuration, sealing, and temperature control as an integrated system.

HONPINE's series of explosion-proof three-joint modules are designed to meet the requirements of robot manufacturers developing intrinsically explosion-proof systems. The modules are designed and manufactured with explosion protection considered across the mechanical structure, electrical system, sealing, and material selection. The products have obtained Ex db IIB T4 Gb explosion-proof certification, supporting compliant use in applicable hazardous areas.

2. High Torque Output for More Than Inspection

The expectations for explosion-proof robots are no longer limited to entering hazardous areas for inspection, photography, and data collection. Increasingly, these robots are expected to perform more demanding tasks such as tool operation, equipment handling, and emergency response.

During these operations, robot joints need to withstand not only the continuous static loads generated by tools and payloads, but also instantaneous impact loads caused by collisions, levering actions, and posture adjustments.

If the peak torque capacity of a joint is insufficient, instantaneous loads can cause torque saturation and motion failure. A joint may be capable of supporting a static load but still be unable to complete practical manipulation tasks when sudden loads occur. Sufficient torque reserve is therefore important for handling both continuous loads and transient impacts while maintaining stable and reliable motion.

HONPINE's series of explosion-proof three-joint modules provides up to 500 N·m peak torque per joint. This high torque capacity provides additional torque reserve for the robot system, allowing the joints to support continuous loads from heavy inspection or operation equipment while also handling transient loads during practical operations.

This helps move explosion-proof quadruped robots beyond the traditional role of “inspection only” toward more demanding field operations.

3. High Environmental Tolerance for Reliable Operation in Harsh Conditions

Dust, moisture, and rapid temperature changes are common in industrial and mining environments. HONPINE follows an automotive-grade design and manufacturing approach, with IP67 protection available as an option, helping the joint modules withstand conditions such as heavy rain, smoke, and high-dust environments.

For explosion-proof quadruped robots operating in hazardous environments, thermal management is also critical. HONPINE follows the relevant GB 3836 explosion-protection requirements for heavy-duty explosion-proof quadruped robot applications. The maximum temperature of exposed surfaces is controlled to ≤135°C, with a corresponding maximum allowable temperature rise of 95 K at an ambient temperature of 40°C.

Temperature warning and shutdown protection mechanisms can also be incorporated to help maintain safe and reliable operation in high-risk environments.

4. High Rigidity for Mobility Over Complex Terrain

Rubble, steep slopes, and uneven ground are typical conditions encountered in hazardous industrial environments. The rigidity and motion control characteristics of the robot joints directly affect the robot's ability to adapt to these conditions.

HONPINE's explosion-proof joint modules adopt a high-rigidity structural design and can be combined with motion-control algorithms optimized for complex terrain. This provides a reliable mechanical foundation for the robot and helps the quadruped platform maintain stable movement across uneven and changing ground conditions.

Robust Core Components for Robots in Hazardous Environments

The development of hazardous-environment robots is gradually moving beyond demonstrations of sophisticated gaits toward reliable operation under real industrial conditions. Whether the core components can withstand actual operating environments has become an important factor in overall robot performance.

Explosion-proof capability, high torque reserve, environmental tolerance, and motion adaptability for complex operating conditions are brought together in HONPINE's series of explosion-proof three-joint modules, providing an integrated solution for high-risk robotic applications.

HONPINE focuses on core components for specialized robots and develops high-load explosion-proof robot joints for system integrators and robot manufacturers. By providing reliable joint actuators for hazardous environments, HONPINE supports the development of robots capable of replacing humans in high-risk operations and contributing to safer industrial production.