State equation of two-dimensional inchworm-type active particles

This study utilized molecular dynamics simulations to explore the collective behavior of the two-dimensional self-propelled particles known as the inchworm particles, which are characterized by periodic variations in internal structure and driving force. Our primary objective is to elucidate the influence of the particle’s motion mode on pressure. We established a state equation for pressure derived from the observed motion mode and observed that inchworm-type particles exhibit distinct high-temperature characteristics in the pressure–temperature curve, unlike spherical self-propelled particles. Notably, their active pressure does not entirely diminish with increasing temperature. Distinct variations in the behavior of self-propelled particles across different sizes are identified. The findings contribute a more intricate model for the internal structure of self-propelled particles, offering valuable insights into this research area.