Buckly-grains: a model system for elucidating interplay of extreme deformations and reconfigurations

AY2022致力于实验设置的实施和分析工具的开发。实验成果（~6个月）。利用3d打印和模塑技术制造可压缩环形颗粒。仔细选择和测试环材料是必要的，以避免引入不良的塑性粘弹性变形。对剪切试验装置进行了改进和改进，以获得整体剪切力和压缩力。实现了一个Labview过程来同时控制和同步驱动电机、摄像头和力传感器。获取既改变环的剪切振幅又改变环的密度的数据集。分析成果（~5个月）。图像分析框架的开发。该方法检测并分离每个环，并测量其跟踪位置、形状和邻域。我们结合了拉格朗日和欧拉分析。从这些测量中，我们探讨了环变形和不可逆位移之间的相互作用。将COMSOL的有限元方法与一维分析开发相结合，使单个环对压痕的机械响应合理化。演讲和发表（约1个月）。在国内和国际会议上展示初步成果，获得业界积极而有价值的反馈。面向高中生（科学对话）和法国研究人员的外展会议。发表(2)和提交(1)在JSPS奖学金之前开始的研究项目。

The AY2022 was devoted to the implementation of the experimental set-up and development of the analysis tools.Experimental achievements (~6 months). Fabrication of the compressible ring-shaped grains using 3D-printing and moulding. Careful selection and testing of the ring material was necessary to avoid introducing undesirable plastic of viscoelastic deformations. Adaptation and improvement of the shear experimental set-up to acquire the global shear and compression force. Implementation of a Labview process to simultaneously control and synchronize the driving motor, the camera, and the force sensors. Acquisition of datasets varying both the shear amplitude and density of rings.Analysis achievements (~5 months). Development of an image analysis framework. The method detects and separates each ring and measures their tracked position, shape, and neighbourhood. We combine Lagrangian and Eulerian analysis. From these measurements, we explore the interplay between ring deformations and irreversible displacements. Rationalization of the mechanical response of a single ring to indentation by combining a finite element approach using COMSOL and a 1D analytical development.Presentations and publications (~1 month). Presentation of the preliminary results in domestic and international conferences, receiving positive and valuable feedbacks from the community. Outreach conferences to High school students (Science Dialogue) and French researchers. Publication (2) and submission (1) of research projects started before the JSPS fellowship.