Experimental and Theoretical Investigation of Quasi-Static System Level Behavior of Planetary Gear Sets

Abstract

This study presents, a unique experimental methodology that synchronously measures various quasi-static responses of a simple four-planet planetary gear set, namely planet load sharing, overall transmission error, and floating sun gear orbits. Strain gauges mounted directly on the planet pins were used to monitor the load shared among the planets, which is a crucial design criterion for durability and performance. High precision optical encoders were used to measure the overall transmission error of the gear set to explore its diagnostic value in identifying system errors. Radial motions of the floating sun gear, which are critical to the self-centering and load sharing behavior of the gear set were monitored using magnetic proximity probes. The influence of various design parameters and operating conditions such as planet mesh phasing, carrier pin position errors, gear tooth modifications, and input torque on the system's response will be investigated by performing an extensive set of experiments in a repeatable and accurate manner. Finally, these experimental results will be recreated theoretically using the static planetary load distribution model of Hu et al. [1] to not only validate the model but also comprehend the measured behavior.

Distinctive behaviors of mesh force and transmission error in mesh stiffness model of spur planetary gear system considering elastic ring gear

“…40 Apart from the vibration signals, researchers have also developed models for condition monitoring and fault diagnosis of planetary gears by using TE signals. 41,42 Although the mesh force cannot be directly measured, some investigations still studied the mesh force behavior 43,44 because an understanding of gear dynamics and an accurate evaluation of the mesh force are essential for the design of planetary gears with low vibration and low noise. 44 Therefore, a comprehensive estimation of TE and mesh force is necessary both in the time domain and frequency domain when studying the planetary gears involved in this paper.…”

Planet Load-Sharing and Phasing

“…[97]; Parker (2000) [98]; Parker and Lin (2004) [99]; Shweiki et al (2016) [100]; Ambarisha and Parker (2007) [101]; Huang et al (2022) [102]; Wang and Parker (2022) [103]; Ryali and Talbot (2021) [49]; Sanchez-Espiga et al ( 2021) [53]. Ryali et al (2021) [34]; Sanchez-Espiga et al (2019) [40]; Sanchez-Espiga et al (2020) [43]; [82]; Zhu et al (2013) [95];…”