Today endoscopic systems are used as the main devices in minimally invasive surgery, but the existing systems are still not able to either move around or perform delicate operations in beating-heart environment. So a new cable-driven soft endoscopic system has been developed to perform cardiac ablation in beating heart. The main inspiration comes from a biological structure of animals called muscular hydrostats. The system is mainly composed of two parts: the endoscopic probe and a feeding station. The probe is the first one in endoscopic devices to be completely made of soft material. And with the cable driving mechanism, an outstanding flexibility and a high degree of freedom has been achieved. The feeding station includes a linear motion system and servos with pulleys. We modified the behavior-based control and designed some behaviors of the system such as blending, wriggling, contracting, etc. Manual and semi-automatic manipulation modes have been presented. Preliminary experiments have been performed to test the maneuverability of our system in limited and unlimited environments. The results show that the cable-driven soft robot has a strong potential in cardiac surgery. The system mechanism turns out to be feasible and we introduced a new idea that the surroundings could play an important role in soft robot control.
Left: An illustration of the new system
Right: the plastic thorax and silicone heart mode(in thorax)