Hinge point optimization and hydraulic cylinder parameter design of the digging arm

Because of the complex working conditions of the arm, its structural design is very difficult. In this paper, the digging arm is integrated by structure and hydraulic systems, and it is designed forward. First a dynamics simulation model of the arm should be established by using dynamics analysis software MotionView and HyperStudy which is a parametric optimization software, the position of each hinge point of the hydraulic cylinder is optimized to find the maximum and minimum installation distances of the hydraulic cylinder which are the most suitable. The dynamic module MotioView is used to calculate the force of the arm under typical postures for determining the cylinder diameter and rod diameter of the hydraulic cylinder. At the same time, all parameters of the hydraulic cylinders are checked mechanically. After that, the compression and tensile stiffnesses of the hydraulic cylinder under typical working conditions are calculated according to the obtained hydraulic cylinder parameters so as to check the overall stiffness of the working arm. Finally, the working arm structure is refined and the structural strength under typical working conditions is analyzed to meet the design requirements. The optimization of the hinge point of the hydraulic cylinder, the design method of the hydraulic cylinder parameters and the stiffness checking method of the working arm described in this paper can be extended to other similar structural designs and have a certain reference significance.