Abstract
An innovative concept for a deployable mast for architectural applications is proposed (Figure 1). Its purpose is two-fold: serving as a supporting mast for an architectural tensile surface structure while acting as an active element during the erection process [De Temmerman].
The mast consists of scissor-like elements (SLE's) which are comprised of bar elements connected by an intermediate pivot joint, allowing a single rotational degree of freedom perpendicular to the common plane of the bar elements. Using scissor units is an effective way of introducing a single D.O.F. mechanism into a structure, providing it with the necessary kinematic properties for the deployment, during which the mechanism transforms from a compact state to a larger, expanded state (Figure 2).
A special kind of scissor unit is used for the structure, consisting of 'angulated elements', which have been extensively investigated and this has yielded a wide range of concepts and applications in the field of deployable scissor structures [Hoberman].
Although primarily intended for radially deployable closed loop structures, especially applied in concepts for retractable roof structures [Jensen], it is shown in this paper that angulated elements can also prove valuable for use in a linear three-dimensional scissor geometry. It is explained how angulated elements offer, for the proposed application, an advantage over polar units in terms of deployment behaviour and a reduction of the number of connections.
As the deployment is an integral part of the design, an insight in the relationship between the geometry of the structure and its subsequent kinematic behaviour is offered. The mobility of the system is assessed through the use of an equivalent hinged-plate model. A purpose-built joint is proposed, allowing all necessary rotations between subsequent elements. Also, a 1/2 scale proof-of-concept model has been built to investigate the deployment behaviour (Figure 3). Finally, the mast is structurally analysed under wind and snow action and conclusions are drawn on the structural feasibility of the proposed design.
The proposed concept has made innovative use of angulated scissor elements in an original application. Although the concept has been proven to work, more detailed analysis, including structural design of the joints, is needed.
The mast consists of scissor-like elements (SLE's) which are comprised of bar elements connected by an intermediate pivot joint, allowing a single rotational degree of freedom perpendicular to the common plane of the bar elements. Using scissor units is an effective way of introducing a single D.O.F. mechanism into a structure, providing it with the necessary kinematic properties for the deployment, during which the mechanism transforms from a compact state to a larger, expanded state (Figure 2).
A special kind of scissor unit is used for the structure, consisting of 'angulated elements', which have been extensively investigated and this has yielded a wide range of concepts and applications in the field of deployable scissor structures [Hoberman].
Although primarily intended for radially deployable closed loop structures, especially applied in concepts for retractable roof structures [Jensen], it is shown in this paper that angulated elements can also prove valuable for use in a linear three-dimensional scissor geometry. It is explained how angulated elements offer, for the proposed application, an advantage over polar units in terms of deployment behaviour and a reduction of the number of connections.
As the deployment is an integral part of the design, an insight in the relationship between the geometry of the structure and its subsequent kinematic behaviour is offered. The mobility of the system is assessed through the use of an equivalent hinged-plate model. A purpose-built joint is proposed, allowing all necessary rotations between subsequent elements. Also, a 1/2 scale proof-of-concept model has been built to investigate the deployment behaviour (Figure 3). Finally, the mast is structurally analysed under wind and snow action and conclusions are drawn on the structural feasibility of the proposed design.
The proposed concept has made innovative use of angulated scissor elements in an original application. Although the concept has been proven to work, more detailed analysis, including structural design of the joints, is needed.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of the 50th Anniversary Symposium of the IASS – “Evolution and trends in Design, Analysis and Construction of Shells and Spatial Structures” |
| Publication status | Published - 2009 |
| Event | Unknown - Duration: 1 Jan 2009 → … |
Publication series
| Name | Proceedings of the 50th Anniversary Symposium of the IASS – “Evolution and trends in Design, Analysis and Construction of Shells and Spatial Structures” |
|---|
Conference
| Conference | Unknown |
|---|---|
| Period | 1/01/09 → … |
Keywords
- Deployable structures