Speleology is the science that studies caves. Currently, with the development and reduction of the cost of
technology, an integral component of speleology is rapidly developing - topographic survey of caves, which
involves determining the shape and size of the cave. The data collected in caves using various instruments
(for example: compass, eclimeter, laser rangefinders) must be processed and visualized. This requires the
appropriate programs. One of such programs is Topo. Topo software allows you to process, edit and visualize the topographic data of the cave. An integral part of the visualization of the topographic survey of the cave is the display of its volumetric model. The volumetric model of a cave is needed to visualize it, to document the caves and to calculate such characteristics of the cave as length, surface area and volume. In addition, with the help of a volumetric model, it is possible to outline the most promising places for further research and search for the continuation of the cave. The aim of this work is to construct a three-dimensional surface of a cave in conditions of sparse data within the Topo program
