Radial Expansion Favors the Burrowing Behavior of Urechis unicinctus

Table 1

The material parameters in constitutive models indicate that the Yeoh model is best suited for the skin constitutive model.

The material parameter	C01 × 10^−4	C10 × 10^−4	C20 × 10^−4	C30 × 10^−4	R^2	Stability
The Mooney–Rivlin model	−585 ± 94.20	293 ± 25.50			0.911	Unstable
The Neo-Hookean model		138 ± 7.78			0.815	Stable
The Yeoh model		88.4 ± 8.06	−3.19 ± 0.75	0.24 ± 0.02	0.995	Stable