*Article* **The Study of Bending and Twisting Input Modalities in Deformable Interfaces**

**Jibin Yin <sup>1</sup> , Shujie Bai <sup>1</sup> , Yi Han <sup>2</sup> , Xiangliang Zhang 3,\*, Siyang Deng <sup>1</sup> and Shuoyu Wang <sup>2</sup>**


**Abstract:** The deformable input provides users with the ability of physical operation equipment to interact with the system. In order to facilitate further development in flexible display interactive technology, we devised FlexSheet, an input device that can simulate the deformation environment. This paper presents two forms of deformation input, bending and twisting, with regard to three selection techniques. We conduct a controlled experiment to select discrete targets by combining two input forms and three selection strategies, taking into account the influence of visual feedback. Further, we use the deformation angle to reflect the degree of deformation and map it to the experimental variables. In accordance with the experimental results, we analyze the experimental performance under three evaluation indexes and prove the viability of our selection technology in bending and twisting input modes. Finally, we provide suggestions on the control level in bending and twisting input modes, respectively.

**Keywords:** flexible display; bending input; twisting input; selection technology
