Analysis of Vibration Characteristics for Rubbing Machine Based on Modal Test

Abstract

Aiming at the problems of large vibrations and noise of a working stalk rubbing machine, this paper took the 9R-60 rubbing machine as the research object and used the B&K modal test system and the vibration test system to analyse the modal and no-load conditions of the whole machine. Through analysing modal test data, it was concluded that the first five natural frequencies of the machine were 95.262 Hz, 144.386 Hz, 288.198 Hz, 313.719 Hz and 326.140 Hz. The results showed that spindle rotation had a more significant effect on the vibration than the feed chain rotation; the maximum vibration acceleration occurred at the small motor frame at a spindle speed of 1700 r·min-1 and a feed chain speed of 0.65 m·s-1, which was 135.539 m·s-2. The distribution of the amplitude statistical characteristics of the vibration signals follows the normal distribution and belongs to the stationary random process. The vibration was a self-excited vibration of the rotating machinery caused by the rotation of the main shaft and a forced vibration excited by the rotation of the same shaft. The research provides a direction for further research on the vibration characteristics of the rubbing machine under load conditions, and provides a theoretical basis for the subsequent vibration reduction design.

A Xanthoceras sorbifolium crack segmentation method based on an improved level set

“…The experimental results show that the level set method can improve the segmentation effect of the semantic segmentation network, especially when the semantic segmentation network is extended to datasets other than network training. There are also many segmentation methods based level set used in agriculture, such as [8–10], which have achieved good results. In recent years, due to its powerful feature extraction ability, deep learning has also been widely applied in agriculture, such as [11–15], and achieved good results in segmentation accuracy.…”

Estimation of the Random Intensity of the Soil Tillage Draft Forces in the Supports of the Working Bodies of a Cultivator

“…More precisely, regarding the series of experimental recordings that form the subject of the analysis whose results are described in this article, they fall into the category of random vibration systems, for which specific approaches are recommended (Meirovitch L., 1976;Buzdugan Gh., et al, 1982;Lalane Ch., 2002;Sireteanu T., et al, 1981). In mechanized work processes in agriculture, vibration analysis has become very frequent, especially with the increase in the quality of agricultural working, with the emergence of precision agriculture and with automation, digitization and robotization in this field (Gong Y., et al, 2023;Yue Y., et al, 2022;Biriş S.Şt., et al, 2022, Yanovych V., et al, 2022Brãcãcescu C., et al 2014, Geng C.X., et al, 2019Samadi M., et al, 2019), for example. Most of the specified authors work for prediction using descriptive statistical estimators, especially the mean value, and lately, inferential statistical analysis is used, especially based on linear regressions, (Rogovskii I., et al, 2020;Colombi T., et al, 2019;Alonso A., et al 2022;Al-Janobi A., et al, 2020).…”

Research on the Spray Cylinder Internal Flow Field and Its Influence on Spraying Quality of Forage Seed Spray Seeding Machine

“…Currently, the main techniques for grassland vegetation restoration include enclosure, artificial seeding, aerial seeding, and pneumatic seeding. Among them, pneumatic seeding is a widely used and effective technique, with relatively low cost and short restoration period (Liang et al, 2015;Yue et al, 2022). It also causes minimal damage to the existing vegetation, making it one of the most effective means of restoring natural grassland vegetation under natural climatic conditions (Mu et al, 2012).…”