An intelligent planetary gearbox based on ultra-compact triboelectric-electromagnetic hybrid generator

In the context of Industry 4.0, constructing an intelligent planetary gearbox (IPG) with self-powered, self-sensing, wireless transmission, and self-diagnosis capabilities is crucial for promoting intelligent upgrades of traditional mechanical equipment. An IPG can realize real-time and accurate remote perception of the operating status, which is beneficial for improving operational reliability and safety. In this study, the ultra-compact triboelectric-electromagnetic hybrid generator (UTHG) is proposed to build an IPG with the aforementioned capabilities. It utilizes the axial space of the planet carrier and end cover for integration with the gearbox. The combination of a triboelectric nanogenerator and an electromagnetic generator can improve energy harvesting efficiency, and their complementarity can drive each module to operate more stably and continuously. The UTHG outputs are evaluated under various working conditions, structural optimizations, and working environments. Consequently, the wireless transmission module integrated with the UTHG is constructed. During operation, the UTHG supplies energy to the wireless transmission module and realizes the wireless transmission of the self-sensing signals. Finally, the fast Fourier transform and convolutional neural network are utilized to diagnose typical faults in the planetary gearbox with a diagnostic accuracy as high as 96.8%. The proposed UTHG provides an effective solution for constructing an IPG.