 We used the gray threshold of the Chinese digital human image dataset to segment an arm image and reconstruct the tissue to obtain its three-dimensional cloud point dataset. This allowed us to construct a semi-refined digital arm entity model with the geometric characteristics of the actual human arm tissue. We then further input the current signal stimulation under TDCS and TAX with additional analysis of the signal diffusion in the transient mode via model calculation. This revealed that DC electrical stimulation is likely to cause high voltage burns while the effective depth achieved using the AC stimulation signal is considerable. Additionally, in the digital arm model, the signal diffusion and tissue damage inside the arm can be analyzed by changing the field, providing a theoretical basis for the experimental study of the human body. This article was authored by Shuang Zhang, Zhou Zheng Wang, Yuan Yu Yu, and others.