S.A.L.I.

What it does

S.A.L.I. mitigates the stresses that surgeons experience during an operation. It's articulating joints and motorized controls address the need for an improved laparoscopic tool that increases maneuverability and comfort.

Your inspiration

The current design of manual laparoscopic devices inhibits the movement of the surgeon where the range of motion of the device is restricted to only two degrees of freedom. In addition, a typical surgical operation lasts for at least two hours. Studies have shown that prolonged use of the manual laparoscopic tools can lead to musculoskeletal injuries such as neuropathy and back pain. In contrast, robotic laparoscopic devices such as Da Vinci, compared to conventional laparoscopic tools, have proven themselves by providing a better experience but at a higher cost.

How it works

The design uses a combination of linkages, servo motors, and electric actuators. It is capable of actuating in four degrees of freedom: grasping, tip rotation, bending, and shaft rotation. It consists of three main parts namely the Tip Division, Middle Compartment and Handle Division. It uses a linkage mechanism to achieve the bending movement as well as a flexible shaft to attain grasping and tip rotation. Servo motors were used to achieve automated motions of the tool while grasping and tip rotation are manually actuated. Anthropometric data from local practitioners of laparoscopy were used in the design of a more ergonomic handle and it features a gamepad-like control for ease of use.

Design process

S.A.L.I. is externally powered and consists of electronic and mechanical units to make the entire system work. The mechanical unit is further divided into the handle, motor housing, main shaft and end-effector. The electronic unit consists of the microcontroller, motors, and other necessary electronic-related components. The electronic unit is necessary in actuating the mechanical unit, which produces physical movement necessary for the tool. The operation starts by plugging the tool to provide electric power. The surgeon then manipulates the control interface of the tool on the handle. This sends signals to the microcontroller, which in turn actuates the rest of the electronics unit. The microcontroller is loaded with a program that coordinates the inputs of the surgeon in the control interface to corresponding actuator movements, which govern the movements of the end effector. Feedback from the mechanical components travel back to the microcontroller, which computes the necessary steps to be taken and prepare the tool for the succeeding series of movements as dictated by the user.

How it is different

Conventional laparoscopic tools offer only two degrees of freedom, tip rotation and a grasping mechanism. The surgeon performs the rest of the movements by moving his/her arms, wrists and fingers. Robotic systems, on the other hand, have ergonomically designed workstations that allow the surgeon the control the laparoscopic tools comfortably. Robotic systems are considered superior compared to manual laparoscopic tools, but these systems cost around 1.5M to 2M USD. As such, S.A.L.I. uses articulating joints to decrease the movement generated by the surgeon. It also simplifies surgical tasks such as suturing or knot-tying.

Future plans

The team plans on designing a fully robotic system based off of S.A.L.I. It will feature different end effectors such as cauterizer, dissector, harmonic scalpel and other tools. It will also feature haptic feedback to provide the surgeon a more realistic sense of touch. With all the added features, the main objective of the robotic system is cost-effectiveness as we plan on selling this device locally.

Awards

Leadership In Innovation Fellowship Grant - Asian Institute of Management; Gold Thesis 2011 - De La Salle University