The design of adaptive structures is one method to improve sustainability of buildings. Adaptive structures are able to adapt to different loading and environmental conditions or to changing requirements by either small or large shape changes. In the latter case, also the mechanics and properties of the deformation process play a role for the structure's energy efficiency. The method of variational motion design, previously developed in the group of the authors, allows to identify deformation paths between two given geometrical configurations that are optimal with respect to a defined quality function. In a preliminary, academic setting this method assumes that every single degree of freedom is accessible to arbitrary external actuation forces that realize the optimized motion. These (nodal) forces can be recovered a posteriori. The present contribution deals with an extension of the method of motion design by the constraint that the motion is to be realized by a predefined set of actuation forces. These can be either external forces or prescribed length chances of discrete, internal actuator elements. As an additional constraint, static stability of each intermediate configuration during the motion is taken into account. It can be accomplished by enforcing a positive determinant of the stiffness matrix.
翻译:适应性结构的设计是提高建筑物可持续性的一种方法。适应性结构能够适应不同的负荷和环境条件,或通过小形或大形变化来适应变化的要求。在后一种情况下,变形过程的机械和特性对结构的能源效率也有一定作用。原先在作者小组中开发的变异运动设计方法可以确定两种特定几何结构之间的变形路径,这些变异式结构对于确定的质量功能来说是最佳的。在初步情况下,学术性设定这种方法假定实现优化运动的任意外部触发力量可以使用每种程度的自由。这些(节奏)力量可以事后恢复。目前的贡献涉及运动设计方法的延伸,其限制因素是该运动将通过预先确定的一组变动力来实现。这些作用可以是外部力量,也可以是规定离散、内部动因要素的长度。作为额外的制约,可以考虑在运动中每个中间组合的静态稳定性。可以通过对坚硬性矩阵进行积极的确定来完成。