Zhenpeng Zhao’s scientific contributions

This study explores the biomechanics of brushstroke dynamics in painting, focusing on the physical demands of different brushstroke types and their underlying kinetic elements. Through an experimental method combining motion capture, force sensors, and electromyography, we analyzed the joint angles, Muscle Activation (MA) patterns, and force application across four brushstroke types: broad strokes, fine detail, stippling, and circular motions. Key findings revealed that broad strokes required the most extensive range of motion, with shoulder and elbow joint angles averaging 45°–60° and 30°–40°, respectively, reflecting the involvement of larger muscle groups in creating expansive movements. Fine detail strokes, in contrast, relied predominantly on wrist flexion and extension (15°–20°), necessitating greater precision and stability from distal muscles. Force analysis showed that stippling generated the highest mean force (10.2 N) due to repetitive dabbing motions, whereas fine detail strokes exhibited minimal force variability, indicating controlled, delicate muscle engagement. Electromyography data indicated peak MA in the extensor carpi radialis and flexor carpi radialis during fine and circular strokes, highlighting the unique demands of rotational and fine motor control in painting. These findings underscore the complex interplay of movement, force, and MA required for different painting techniques, contributing valuable insights for optimizing technique and preventing repetitive strain in artists. This research provides a foundational biomechanical understanding of brushstroke execution, with implications for art education, rehabilitation, and ergonomic interventions in the arts.