# AnyGesture: Arbitrary One-Handed Gestures for Augmented, Virtual, and Mixed Reality Applications
## 5 Conclusions  
In this work, a framework for the design and implementation of one-handed gestures is proposed. It can be used to implement natural user interactions within a wide variety of immersive AR, VR, MR, and desktop applications. Existing hand tracking solutions serve as an entry point to the framework, and the necessary data are redistributed to internal components. These components are responsible for recording, storing, recognizing, and interpreting gestures. The detected gestures can be integrated into applications with events, such as gesture completion, activation, deactivation, failed, and progress. The goals of the framework are a simple gesture creation process and the recognition of any one-handed gesture. The evaluation confirms that the main objectives of the framework have been achieved. Static and dynamic gestures can be recorded by performing the desired gesture and subsequently pressing a key. For static gestures, hand shape and orientation is stored. Dynamic gestures can be recorded by monitoring joint positions and storing the spatial differences into a doubly linked list. To allow a wide range of complex gestures, several solutions are proposed to enhance and improve gesture recognition. Furthermore, a system to evaluate the framework was built. A user study with 33 participants was conducted, and gestures designed with the framework were evaluated. Overall, the system showed promising results. Gestures designed and implemented by a single person can be reliably reproduced by others without the need for elaborate data sets to define new gestures. The core of this work is the ease of adding new gestures that are reliably recognized and directly applicable. By not requiring data sets, training, or expert knowledge to implement new gestures, it allows integration into a variety of applications. Even complicated gestures can be easily recorded and tested for usability. The multitude of possible gestures is only limited by the creativity of the users. This work aims to encourage researchers to create gesture-based applications and then examine them for usability, feasibility, and other measures. It paves the way for systems to design, prototype, evaluate, and support arbitrary gestures. Conceptualization, A.S. and G.R. ; methodology, A.S. and G.R. ; software, A.S. and G.R. ; validation, A.S. and G.R. ; formal analysis, A.S. and G.R. ; investigation, A.S. and G.R. ; resources, A.S. and G.R. ; data curation, A.S. and G.R. ; writing--original draft preparation, A.S.; writing--review and editing, A.S. and G.R. ; visualization, A.S.; supervision, G.R. ; project administration, G.R. ; funding acquisition, D.S. and G.R. All authors have read and agreed to the published version of the manuscript. Part of this work was funded by the Bundesministerium fur Bildung und Forschung (BMBF) in the context of ODPfalz under Grant 03 HS075B. This work was also supported by the EU Research and Innovation program Horizon 2020 (project INFINITY) under the grant agreement ID: 883293. The authors declare no conflict of interest. The following abbreviations are used in this manuscript: \begin{tabular}{l l} AR & Augmented Reality \\ ASL & American Sign Language \\ HMD & Head Mounted Display \\ HMM & Hidden Markov Model \\ MDPI & Multidisciplinary Digital Publishing Institute \\ MR & Mixed Reality \\ SDK & Software Development Kit \\ SVM & Support Vector Machine \\ VR & Virtual Reality \\ \end{tabular}   
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