Abstract: When the structure of the working attachment of hydraulic excavators is analyzed by means of the tradi- tional classification method,one tip position of buckets only corresponds to one attitude.Therefore,the analysis is incomplete.In order to solve this problem,by taking the working attachment as a whole,a method (MBRS-3D) of 3D atlas of the maximum stress and corresponding stress atlas based on a regional planning is proposed to explore the structural characteristics of the hydraulic excavator attachment,and the maximum stress is taken as an example to conduct an analysis.Then，the excavation resistance coefficient and the resistance moment coefficient are ac- quired by testing and statistics,and a calculation model of the theoretical digging force is constructed.Based on the regional planning of the working attachment with variable parameters,an integrated finite element analysis of the working attachment is implemented,thus obtaining the maximum stress values and the corresponding key area num- bers of the boom,the stick,the bucket and the whole excavator attachment.Afterwards,the 3D atlas of the maxi- mum stress and the corresponding region are drawn to visually describe the maximum stress value and the value dis- tribution.Finally,the dangerous working condition is selected through the proposed method,and it is compared with the classic condition.The results show that the selected dangerous working condition is more dangerous than the classic one.

Key words: excavator attachment, three-dimension atlas, regional planning, integrating analysis, stress character- istic, dangerous working condition