DOI: 10.17587/prin.16.81-91

Application of the Finite Element Method to Stabilize a Character's Head in Computer Animation

A.S. Zabiyako, Master of Science, FIIT, szabiyako@gmail.com, E. V. Trofimenko, Ph.D., Associate Professor, evtrof@gmail.com, Voronezh State University, Voronezh, 394018, Russian Federation, I. V. Khmeleva, Ph.D., Associate Professor, hmelevai@gmail.com, B. N. Yeltsin Kyrgyz-Russian Slavic University, Bishkek, 720000, Kyrgyzstan

Corresponding author: Elena V. Trofimenko, Ph.D., Associate Professor, Voronezh State University, Voronezh, 394018, Russian Federation, E-mail: evltrof@yandex.ru

In today's entertainment industry, the rapid development of technology has led to the emergence of a large number of innovative ways to create visual effects. However, the task of improving the efficiency of work with footage remains relevant and in demand. To record an actor's performance, one usually uses either a photogrammetric setup consisting of a bunch of cameras placed around the actor, or a helmet with fixed cameras filming the actor's face. Despite the undeniable advantages of this approach, compared to manual animation, it has a number of disadvantages. These include the cost of processing photogrammetry for each frame of animation and the subsequent stabilisation of the actor's head position. Problematic issues related to stabilisation of facial animation are caused by the need to adjust the position of the head in each frame of animation so that from frame to frame the head does not change its position in space, and the changes would occur only in the facial expressions of the actor. Despite the widespread use of photogrammetry to capture the faces of actors, the process of stabilising the position of the head is still complex and poorly automated. In the presented article the existing methods of stabilisation are considered: interactive nearest point algorithm (ICP), alignment by key points, ICP with weight mask and Rigid Stabilization of Facial Expressions proposed by developers of Disney studio. Their comparative analysis is carried out. A new stabilization method is proposed in which the finite element method is used to approximate the flesh behaviour more accurately. The deformation gradient, skull displacement and flesh deformation formulas are generated to implement this method. The results of approbation of the application and comparison of the performance of the proposed method with others are presented. The analysis of the results showed that the application of the developed method of character head stabilization is effective and allows to significantly improve the quality of the created computer animation.

Keywords: muscle simulation, finite element method, neo-Hookean energy, skull stabilization, deformation gradient

pp. 81—91

For citation:
Zabiyako A. S., Trofimenko E. V., Khmeleva I. V. Application of the Finite Element Method to Stabilize a Character's Head in Computer Animation, Programmnaya Ingeneria, 2025, vol. 16, no. 2, pp. 81—91. DOI: 10.17587/prin.16.81-91. (in Russian).

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