In-depth Analysis of Vibration Noise Causes Enhancing Upgrades for Humanoid Robot Joint Modules

Nugle: In-depth Analysis of Vibration and Noise Causes, Empowering Upgrades for Humanoid Robot Joint Modules

As the industrialization of humanoid robots accelerates, the joint module, which serves as the core unit for movement execution, directly influences the smoothness of robot actions, operational reliability, and human-robot interaction experience. Currently, issues of vibration and noise have emerged as critical bottlenecks hindering the performance enhancement of joint modules. These problems not only affect the precision of robotic gaits and shorten the lifespan of core components but also restrict their deployment in scenarios such as healthcare and home services, where silence is paramount.

After industry technical assessments, it has been identified that the generation of vibration and noise in humanoid robot joint modules primarily stems from four core causes: transmission, structure, assembly, and operating condition compatibility. Each of these factors interacts with and amplifies the others.

• Firstly, insufficient precision in transmission components, such as harmonic reducers and planetary gearboxes, leads to tooth profile errors, excessive tooth side gaps, and high surface roughness. These issues can cause impacts and friction during meshing, which are the main sources of vibration and noise.
• Secondly, inappropriate structural design and material compatibility can hinder performance. The joint module must balance light weight and compactness; however, some designs overlook vibration damping. Poor damping characteristics of the joint casing fail to effectively absorb vibrations and block noise, leading to component resonance.
• Thirdly, non-standard assembly processes, including misalignment of the shaft system and improper bearing gap adjustments, can cause component collisions and increased friction during operation, further exacerbating vibration and noise issues.
• Lastly, incompatibility with operating conditions and lubrication failures, particularly during high-load operations, can cause torque fluctuations in motors and frequent switching of joint actions, leading to torsional vibrations. Additionally, inappropriate lubricants may fail in extreme temperatures, preventing the formation of a stable oil film and increasing friction between metal contacts, resulting in a vicious cycle of “temperature rise – lubrication failure – increased noise.”

Industry research indicates that over 60% of operational failures in humanoid robots are related to vibration and noise issues caused by the above factors. In response, Nugle has implemented precise strategies and introduced systematic improvement measures across four dimensions to comprehensively tackle the vibration and noise challenges.

• In optimizing core transmission components, Nugle aims to enhance the processing precision of harmonic reducers and planetary gearboxes, optimize tooth contour design, reduce tooth side gaps and meshing impacts, and pair high-precision bearings to minimize friction noise. Additionally, specialized wide-temperature lubricants will be used to ensure stable oil film formation under complex operating conditions, avoiding lubrication failure.
• For structural and material upgrades, high-damping composite materials will be used for joint casings, along with 3D-printed hollow buffering structures to enhance vibration absorption. The servo motor and harmonic reducer will be highly integrated to reduce component collisions and resonance risks while maintaining light weight and quiet operation. Some solutions can achieve operational noise levels as low as 22 decibels.
• Regarding assembly control, standard assembly procedures will be established, and high-precision equipment will be utilized to calibrate shaft system alignment and component gaps, improving assembly consistency and eliminating human error.
• For operating condition optimization, AI motion control algorithms will be upgraded to ensure smooth switching of joint actions, reducing vibrations caused by torque fluctuations. Furthermore, high-precision, high-strength damping structures will be introduced, akin to adding “ligaments” to joints, minimizing vibration transmission and noise generation.

Currently, these improvement measures have shown significant results, successfully reducing the operational noise of joint modules to below 45 decibels and controlling vibration amplitude at the micrometer level. This represents a reduction in vibration noise of over 40% compared to traditional products, meeting the mass production needs of leading domestic humanoid robot companies and breaking foreign technological monopolies.

Looking ahead, Nugle will continue to deepen its research into causes and iterate its measures, tailoring improvement solutions to the specific needs of humanoid robot applications. The company aims to further reduce manufacturing costs and advance joint modules towards low vibration, quiet, and efficient upgrades, helping domestic humanoid robots overcome core technological barriers and accelerating their industrialization, thereby injecting new momentum into the autonomous and controllable development of the intelligent equipment manufacturing industry.