# In Search of Lightweight Deployable Tensegrity Columns
## 6 Conclusions  
The analyses presented in this study proved that it is possible to build a deployable supporting structure for civil engineering applications using a tensegrity system. The question was: Which of the analyzed columns is most appropriate for this task? As can be seen in the Results Section, there is no straight answer to this question. Depending on the specific application in which the column needs to be used, different systems can be indicated.  
The simplex and overlapped simplex columns are the most popular in the literature because the basic simplex module is very plain, well described, and easy to connect. However, the authors proved that even though these two columns have the best compression ratio, they are rather complicated to control and are unstable during the deployment process. Moreover, the overlapped layout is not that simple to control due to the large amount of actuators. Therefore, the popular columns based on three-strut simplex patterns are not recommended as supports of civil engineering structures. They could be selected only in cases where the volume of the package is crucial, for example from the transportation point of view.  
Analysis of the results presented in this paper leads to the conclusion that the most appropriate columns for the assumed application are X and octahedron columns. The X column in its second deployment scenario demands the least active cables and the least actuators. It is the lightest one and has a fair compression ratio due to the fact that it can be made entirely flat for storing. On the other hand, it demands the most space for deployment, so when this is an issue, the second best is the octahedron column, which demands the least space and is still reasonable to control. The X column is also most compliant, which can be advantageous when dynamic loads come into consideration. Alternatively, the octahedron column is the stiffest one. It has the highest load carrying capacity, so it is recommended for use in heavier structural systems or with bigger live loads.  
Taking into account all the obtained results, the authors recommend using X columns as additional supports of temporary or lightweight structures (tents, temporary ceilings, etc.) and octahedron columns as supports of heavier structures where the high load carrying capacity plays an important role.  
This research, consisting of broad FEM and MBD analyses, provided all the necessary data for building small- and then medium-scale real models for laboratory tests. At this stage of the research, the authors validated the applied method numerically, by comparing self-stress states at various steps of the analysis. When the real models of the structures are constructed, a further validation is planned using the data from the laboratory tests. After this step, the authors aim at building a full-scale object. This data may also be used as a starting point for research in other fields of science like robotics or mechatronics.  
The research was performed by the authors as follows: conceptualization, A.A.S.-Z. and A.Z.; methodology, A.Z.; software, A.A.S.-Z. and A.Z.; validation, A.A.S.-Z. and A.Z.; formal analysis, A.A.S.-Z.; investigation, A.A.S.-Z. and A.Z.; writing and editing, A.A.S.-Z. and A.Z.; supervision, A.Z. All authors read and agreed to the published version of the manuscript.  
This research was funded by Warsaw University of Technology  
The authors would like to thank Professor [PERSON] for all the guidance and comments during the performance of the analyses and the preparation of the paper. Calculations using the MSC Adamssoftware were carried out at the Academic Computer Centre in Gdansk.  
The authors declare no conflict of interest.  
The following abbreviations are used in this manuscript:  
DOF Degree of freedom  
FEM Finite element method  
LCC Dimensionless load carrying capacity  
MBD Multibody dynamics