Design and Evaluation for a Soft Intra-Abdominal Wireless Laparoscope

In single-incision laparoscopic surgery (SILS), magnetic anchoring and guidance system (MAGS) is a promising technique to prevent clutter in the surgical workspace and provide a larger vision field. Existing camera designs mainly rely on a rigid structure and sliding motion, which may cause stress concentration and tissue damage on curved abdominal walls. Meanwhile, the insertion procedure is also challenging. In this paper, we proposed a wireless MAGS consisting of soft material and wheel structure design. The camera can passively bend and adapt to the curved tissue surface to relieve stress concentration. The wheel structure transfers the sliding motion to rolling motion when the camera tilts and translates, avoiding tissue rupture due to dry friction and facilitating smooth motion. The experiments show the novel laparoscope has dexterous locomotion and bendability with 20° in bending angle and $16.4mm$ in displacement. The maximum stress is reduced by 64% compared with rigid designs. An easy and safe insertion procedure based on soft property is also introduced, which takes less than 2 minutes on average without the assistance of additional instruments.