Effects of Spine Motion on Foot Slip in Quadruped Bounding

Table 3

Result for crawling robot.

Case	Spring type	K (N·mm^−1)	Crawling time (s)	Performance improvement over the rigid case
1	Linear spring, normal	7.54	16.11	8.05%
2	Linear spring, hard	16.42	16.46	6.05%
3	Linear spring, soft	3.60	17.31	1.20%
4	Rigid	∞	17.52	0.00%
5	Linear spring, very soft	0.51	17.84	−1.83%

The spine stiffness of crawling robot with rigid spine is ∞.