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In this paper, cushion suspension support system of low speed and heavy loading of the gas membrane flow field was in computational fluid dynamics analysis, explore the influence of air cushion suspension of performance support system air cushion structural parameters, and the air pressure in the process of air cushion lift proportional control system for mathematical modeling, thus to control the thickness of air cushion, based on pole assignment self-tuning controller, to improve the response and stability of the system, and the system in this paper the lifting process of air cushion suspension support system are analyzed and the gas film flow state, deepening the theoretical research of air cushion suspension technology.

PurposeIn this paper, the main factors influencing the structure stiffness will be analyzed by studying the tangent stiffness matrix based on different requirement in engineering practice. The authors can obtain the deformation of three-bar tensegrity basic unit in different load, and gain the primary factor by comparing the deformation, which will provide reference to concrete structure design in the engineering.Design/methodology/approachThe mathematical model of tensegrity structure was built by establishing generalized node coordinates and connective matrix. Three main factors that affect the structure deformation can be obtained by analyzing the stiffness matrix, which is preload, Young's modulus, and cross-sectional area, the thinking of deformation also be sorted out. The deformation analysis of the concrete structure is carried out, and it is concluded that increasing the cross-sectional area can quickly improve the stiffness of the structure, which provides a reference for the structural variable stiffness design in practical engineering.Findings(1) When the axial external force is applied to the structure, the torsion-angle deformation of the structure is the largest, and the radial deformation of the structure is the smallest. (2) The structure stiffness can be rapidly enhanced by increasing the cross-sectional area. But the cross-sectional area can't be increased indefinitely. Because the mass will be increased once increasing the cross-sectional area, which will destroy the structure of the advantages of light weight in engineering practice.Originality/valueThe deformation analysis of the concrete structure is carried out, and it is concluded that increasing the cross-sectional area can quickly improve the stiffness of the structure, which provides a reference for the structural variable stiffness design in practical engineering.

PurposeThis paper is contributed to find the minimal mass prismatic tensegrity structures.Design/methodology/approachIn the stable state of the structure with any given external force, the internal forces of the structure members are taken as the critical force to calculate the cross-sectional area, and the total mass of the structure can be obtained. Firstly, the mathematical model of prismatic tensegrity was built. Secondly, the stability of the tensegrity was analyzed based on the force equilibrium of one node, the force density relationship of elements was obtained. The deformation of p-bar tensegrity prism unit was studied with the same mass. The force of the structure under external force was analyzed.Findings(1) The length of bar and the structural radius are almost invariant, and the mechanical properties of 3-bar tensegrity prism is more outstanding; (2) theoretically, the mass of the structure is minimal while the projection of bar passes the center of the circle. Under the circumstances, the force of diagonal cable is 0 N, the vertical force component of bar cancels the axial external force.Originality/value(1) By analyzing the deformation of p-bar tensegrity prism with the same mass, the length of bar and the structural radius are proved be almost invariant and the mechanical properties of 3-bar tensegrity prism is more outstanding; (2) theoretically, the mass of the structure is minimal while the projection of bar passes the center of the circle. Under the circumstances, the force of diagonal cable is 0 N, the vertical force component of bar cancels the axial external force.