Fig. 4.

Finite element simulations of the cellular traction force experiments conducted using the measurements and observations of Dembo et al. [12]. Computations were performed assuming a linear elastic response for the PAG substrate, with Poisson ratio and Young’s modulus equal to 0.48 and 6.78 kPa, respectively. (A) Displacement vectors of latex beads during fibroblast locomotion as reported in Dembo et al. [10]. (Reprinted with permission ©1999, Biophysical Society.) (B) Computed displacements of the PAG substrate. (C and D) Top and side views color maps showing the computed displacement field (C) and effective strains field ε_eff (D). The effective strain is defined as: ε_eff = (2e_ij e_ji/3)^1/2, where e_ij are the deviatoric components of the strain tensor. Side views of the displacement and strain fields are given along the section plane defined by the dashed lines on (C) and (D).