In recent years, research on shape-changing user interfaces composed of collective objects has been conducted extensively. With advancements in semiconductor technology, there is a prospect of miniature wireless-connected computers cooperating to achieve interaction through shape changes. To realize this prospect, the issue of shape estimation among multiple computers becomes crucial. Given the large number of computers involved, it’s more efficient to limit communication to nearby nodes. Ideally, shape estimation should be performed using only neighboring nodes. However, in such a model, where all distances are equal, solving the shape estimation problem from a network graph is known to be NP-hard. In this study, we propose a method that enables shape estimation by imposing constraints on the physical layout, using information from neighboring nodes only. Our approach achieves initialization in O(n) and addition or disconnection in O(1). Shape estimation is expected to facilitate more intuitive interaction with users and support the construction of high-throughput networks. To validate the proposed algorithm, we created a prototype of a shape-changing display and demonstrated shape estimation. This validation underscores the algorithm’s potential as a cornerstone for future shape-changing interface technologies.