• Journal of Korean Association for Spatial Structures
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• v.14 no.4
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• pp.55-64
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• 2014

In this study, Intersecting Tensegrity System that is integrated solid compression members with tension members was presented. This system is set up by connecting upper and lower compression members of pyramid shape with exterior tension members. In this system, the solid compression members are intersected each other and connected by a tension member in the center. This system is a variation of Tensegrity system, has a improved feature that the system is able to induce prestresses in all of tension members easily by adjusting the distance of a tension member in the center. The proposed system was studied by modeling, and the structural behavior of the system was investigated by mechanical analysis of the model. Furthermore, the features of the structural behavior variations was investigated when the composition elements(total height, size of surface, intersection length, etc.) are changed variously. It was also showed that the system is able to be used as a temporary space structure system with a membrane roof of inverse conical shape.

• Proceeding of KASS Symposium
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• 2008.05a
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• pp.189-194
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• 2008

The main object of this paper is that it's possible to monitoring the deformation of cable in the tensegrity structure. always monitoring system of Fiber Bragg Grating(FBG)Sensor is described. The measurement of parts on the cable is very important. We make an experiment with measuring deformation of cable in the tensegrity structure to the pressure conditions. In the result of experiment, the fiber sensors showed good response to the pressure conditions. Therefore, We could calculate the deformation of cable structure and be possible health monitoring of the tensegrity structure.

• Journal of Korean Association for Spatial Structures
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• v.3 no.4 s.10
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• pp.77-84
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• 2003

Tensegrity systems are stable structures which are reticulated spatial structures composed of compressive straight members, struts and cables. But there are some difficulties concerning surface stability, surface formation and construction method. One of the ways to solve this problem reasonably is combination of tesile members and rigid members. This structure is a type of flexible strutural system which is unstable initially because the cable material has little initial rigidity. Therefore tensegrity structure need to be introduced to the Initial stress for the self-equilibrated system having stable state. The rigidification of tensegrity systems is related to selfstress states which can be achieved only when geometrical and mechanical requirements are simultaneously satisfied. In this paper, for the stabilization of tesnsegrity structure it is proposed the modified self-equilibrated equation and the range of the various geometrical parameter about unit system. And we generate the model of double layed single curvature arch using the new squew quadruplex unit system.

• Journal of Korean Association for Spatial Structures
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• v.5 no.2 s.16
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• pp.81-87
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• 2005

The Space structures may have large freedom in scale and form. And especially Hybrid structures are received much attention from the view points of their light weight and aesthetics. Hybrid systems are stable structures which are reticulated spatial structures composed of compressive straight members, struts and cables and Membranes. In this paper, The Hybrid Unit System are suggested using the Membrane and Cable elements based on the Tensegrity Unit system. Also, The Hybrid System of double-layered single curvature is presented. We analyze the force density method allowing form-finding for Tensegrity systems. And We analyze the shape analysis by the LARSH which is the program for nonlinear analysis.

• The Journal of Korea Robotics Society
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• v.19 no.1
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• pp.1-7
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• 2024

This paper presents an under-actuated robotic hand inspired by the ligamentous structure of the human hand for a prosthetic application. The joint mechanisms are based on the concept of a tensegrity structure formed by elastic strings. These rigid bodies and elastic strings in the mechanism emulate the phalanx bones and primary ligaments found in human finger joints. As a result, the proposed hand inherently possesses compliant characteristics, ensuring robust adaptability during grasping and when interacting with physical environments. For the practical implementation of the tensegrity-based joint mechanism, we detail the installation of the strings and the routing of the driving tendon, which are related to extension and flexion, respectively. Additionally, we have designed the palm structure of the proposed hand to facilitate opposition and tripod grips between the fingers and thumb, taking into account the transverse arch of the human palm. In conclusion, we tested a prototype of the proposed hand to evaluate its motion and grasping capabilities.

• Journal of Korean Association for Spatial Structures
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• v.8 no.1
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• pp.49-56
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• 2008

A multi-objective optimization approach is presented for force design of tensegrity structures. The geometry of the structure is given a priori. The design variables are the member forces, and the objective functions are the lowest eigenvalue of the tangent stiffness matrix that is to be maximized, and the deviation of the member forces from the target values that is to be minimized. The multi-objective programming problem is converted to a series of single-objective programming problems by using the constraint approach. A set of Pareto optimal solutions are generated for a tensegrity grid to demonstrate the validity of the proposed method.

• Journal of Korean Association for Spatial Structures
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• v.10 no.2
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• pp.87-94
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• 2010

Form-Finding of tensegrity structures by eigenvalue problem is presented, In ardor to maintain the structures stable, "Form-Finding" should be performed. The types of analytical methods are known to solve this phenomenon: One is to use force density method, and the other is to apply so called, generalized inverse method. In this paper, new form finding methods are presented to obtain the self-equilibrium stress of the tensegrity structures. This method is based on the equilibrium equation of the all of the joint and the governing equation is formulated as eigonvalue problem. In order to verify this approach, numerical example(tensegrity structures) are compared with others calculated by previous methods. The solution by present method is shown identical results. Furthermore, the developed process to find the results is more efficient than previous approaches.

• Journal of Korean Association for Spatial Structures
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• v.12 no.1
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• pp.69-75
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• 2012

The purpose of this paper is to study comparative analysis of cable dome structures by reinforcement effect with bracing and fabric. Tensegrity systems are stable structures which are reticulated spatial structures composed of compressive straight members, struts, and cables. Tensegrity structures need to be introduced to the initial stress for the self-equilibrated system to have a stable state. In this paper, the effect of reinforcement resisting the in-plan twisting is investigated for the Geiger-type and Zetlin-type models reinforced by bracing and fabric. The effect of initial imperfection is also studied because the structural instabilitity phenomenon of shell-like structures is very sensitive according to the initial condition. We study a more exact analysis concerning the structural instability of tensegrity structures using nonlinear analysis program. Then, two types of tensegrity models will be analysed and compared.

• Journal of Korean Association for Spatial Structures
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• v.7 no.3 s.25
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• pp.125-132
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• 2007

The purpose of this study is to investigate the functions and formations of the component units as aesthetic components in the spatial grid. The main subject covered here is the presentation of the morphological method of shaping spatial grid by application of 3-dimensional units satisfying the suitable form of polyhedra, tensegrity and hybrid structure. In accordance with the subject, the definition of the spatial grid and 3-dimensional nit, the relationship between them, and then the functions of those units are reviewed. And the formations of polyhedral units, tensegrity units and hybrid units are generated by means of the modules of the simplest type or pattern. And also the overall appearance of the spatial grid shaped by several basic methods in which one unit can be joined to another and arranged are depicted.

• Steel and Composite Structures
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• v.49 no.2
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• pp.125-141
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• 2023

Firstly, a new kind of prismatic tensegrity structures with redundant cables is defined, the topology, geometry and forming conditions of which are introduced further. The development of its mechanical properties including self-stress states and structural stiffness with the increment of the twist angle is also investigated carefully. Combined with the topology of this kind of structures, a reasonable erection scheme is proposed, in which some temporary lifting points need to be set and two groups of vertical cables are tensioned in batches. Then, a simplified dynamic relaxation method is employed to track the erection process inversely, which aims to predict each intermediate equilibrium state during the construction, and give the key structural parameters that can effectively guide the construction. The removal of the active cables, the relaxation or tension of the passive cables are simulated by controlling their axial stiffness, so that the structural composition as well as the serial numbers of the elements always keep invariant regardless of the withdrawal of the slack cables. The whole analysis process is clear in concept, simple to implement and easy to popularize. Finally, several examples are given to verify the practicability and effectiveness of the proposed method further.