2.7. Experimental Tests to Assess the Instruments RCM Displacement Risk (MH3)

The endoscopic camera orientation will alter the RCM position of the two modules during the SILS procedure, as presented in Figure 10. A set of experimental tests have been performed to assess the intercostal muscle strain limits using pork tissue. The test bed is presented in Figure 11 and consists of: the Instron 3366 Universal Testing Machine [46], a monitoring camera (with PC) and pork tissue. Seven tissue samples from various areas of the pork’s body have been tested (Figure 12), where the pork tissues have been gripped using industrial steel hooks (with a diameter of Φ6 mm) between the machine’s grippers. The speed used for the experiment was 10 mm/min for samples 1–5 and 20 mm/min for samples 6–7. During the tests, the tissue samples were extended (stretching the intercostal muscles) until the registered force started to decrease, showing that the muscle fibers had broken (and the tissue was being detached from the ribs).

The SILS instruments RCMs displacement during the endoscopic camera orientation: (a) transversal section. (b) isometric view.

The intercostal muscles strain test bed.

The pork intercostal muscles tested samples.