The objective of this paper is to discuss the characteristics of a family of space structures that are referred to as 'nexorades'. Typically, a nexorade is constructed from scaffolding tubes, connected together with swivel couplers. An important application of nexorades is for shelters of various sizes and shapes for temporary or permanent purposes. In such a shelter, the structural skeleton is provided by a nexorade and the cover is provided by a membrane material

This is the first paper in a series of papers that are intended to cover the present state of knowledge in the field of formex configuration processing. This field of knowledge has been developed during the last three decades and has now reached a level of maturity that makes it an ideal medium for configuration processing in many disciplines. In particular, it provides a rich assortment of concepts that are of great value to the engineers and architects involved in the design of space structures.

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This is the third paper in a series of papers that are intended to provide a comprehensive coverage of the concepts of formex configuration processing and their applications in relation to structural configurations. In the present paper, the attention is focused on structural forms that are based on hyperbolic paraboloidal, hyperboloidal and annular surfaces. It is shown that these categories of structural forms include many exciting possibilities for lattice and shell structures. The paper also includes sections on structural forms that may be obtained from combinations of simpler forms or through certain composite transformations that are called paragenic transformations.

This is the second paper in a series of papers that are intended to provide a comprehensive coverage of the concepts of formex configuration processing and their applications in relation to structural configurations. In the present paper, attention is focused on the configuration processing for a number of families of space structures, namely, pyramidal forms, towers, foldable systems and diamatic domes . Also included is a section on information export as well as an Appendix on basic formex functions. The section on information export describes the manner in which the information about the details of a configuration, generated by the programming language Formian, can be exported to graphics, draughting and structural analysis packages.

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Abstract. The objective of this paper is to discuss the characteristics of nexorades based on regular polyhedra. An important application of nexorades is for shelters of various sizes and shapes for temporary or permanent purposes. In such a shelter, the structural skeleton is provided by a nexorade and the cover is provided by a membrane material.

In this paper, the method of genetic algorithm is used as a search technique to find the stability characteristics of simultaneously statically and kinematically indeterminate structures The genetic algorithm is used to find out if there is a solution for a specific quadratic form which has to be satisfied in order to guarantee the statical stability. The genetic algorithm is a search technique that imitates nature in selecting and optimising towards an aim. The use of the genetic algorithm in the search for the stability of pin-jointed structures is found to be simple and powerful. A computer program called STAPS (Stability of Pin-jointed Structures) has been developed using the genetic algorithm. This program firstly identifies the independent mechanisms and states of self-stress, if any, in a structure. Then, the program searches for any state of self-stress that can stabilise all the mechanisms of the structure. STAPS program is a powerful tool for finding the stability of 2D and 3D pin-jointed structures. The program can be used for investigating the stability of space trusses and cable structures like cable nets, cable-strut and tensegrity structures1,2. Section 1 of this paper contains a brief introduction. Section 2 discusses the background of what is called ‘product forces’. Also, in Section 3 the stabilisation of mechanisms of pin-jointed structures is discussed. Section 4 introduces the method of genetic algorithm and how it is used in the search for stability of pin-jointed structures. Section 5 introduces the STAPS program together with illustrative examples of its application. Finally, Section 6 gives a conclusion of the work presented in this paper.