Tomas Lenssen

Introduction: Most robotic instruments and their drives still risk residual contamination due to cleaning complexities, rendering them limited reusable, and tend to have larger instruments than the 5mm laparoscopic standard. The novel steerable laparoscopic SATA-LRS uses modularity for cleanability and exchangeability. The SATA-Drive: a robotic driver designed for the actuation of a 3mm scaled version of the SATA-LRS is presented. Methods: A modular, expandable gear mechanism was designed to efficiently rotate and translate the instrument shafts. The 3mm SATA-LRS is controlled as proof. An user-experiment is conducted to test the (de)coupling of the instrument to and from the drive. Results: A video shows the SATA-Driver successfully articulating, rotating and grasping the end-effector. End-effector dis-and reassembly is possible in 36 (13 SD) seconds, while complete instrument coupling requires 28(8 SD) seconds and de-coupling requires 16 (7 SD) seconds. Discussion: A non-surgical robot arm, mounted with the SATA-drive has effectively been transformed into a system similar to robot assisted laparoscopy. The modularity of the drive’s segmented build can easily be adapted and could benefit the adoption of future instruments. The SATA-LRS’s cleanability features and its end-effector changes without disassembly are expected to benefit medical robotics. The 3mm SATA-LRS shows the instrument’s potential for mini-laparoscopy.

Introduction:Based on the success of the former “Shaft-Actuated, Tip-Articulated” SATA-Drive, a prototype robotic instrument driver for modular, steerable, laparoscopic instruments, a new driver is designed and tested to improve previously lacking features concerning cleanability, instrument adaptation, practical application and control. The design of the driver engages these issues with a modular design aimed at re-use of both the instrument and the driver, for which a set of design requirements are established.Methods:A new modular design has been developed to improve cleanability through separation of the electro-motors and the instrument mechanism which clutches the instrument. Contamination of the driver’s robotic side is prevented though a combination of a drape and a Sterile barrier interface, while the instrument side is made sterilizable. A novel instrument clutching mechanism enables quick-release features, while a motor-axis latching mechanism enables plug-and-play assembly. Embedded sensors allow precise and fast control. A user-experiment was conducted on instrument exchange and assembly time, while mechanical and electrical tests were conducted on the driver’s responsiveness.Results:The driver has proven its ability to control the instrument, after which it can be disassembled for cleaning and inspection. The driver is designed for re-use through disassembled sterilization where all possibly contaminated surfaces are exposable for cleaning and inspection. The new standardized instrument clutches allow easy instrument (dis-)assembly. Instrument exchange is possible in two methods, the fastest of which is a median of 11 (6.3–14.6) seconds. The driver’s instrument mechanism is separated in a median of 3.7 (1.8–8.1) seconds. After assembly, the driver is operational in less than 2 s.Discussion:Instrument exchange times are similar to the semi-reusable Da Vinci systems, yet the MISLI-Drive is designed for sterilization, inspection and continual re-use. The modular build of the driver also allows easier parts replacement during maintenance, and requires minimal adaptation to different future scenarios, which is expected to reduce the overall cost of use.

Hospitals in low resource settings (LRS) can benefit from modern laparoscopic methodologies. However, cleaning, maintenance and costs requirements play a stronger role while training and technology are less available. Steerable laparoscopic instruments have additional requirements in these settings and need extra identified adaptations in their design. Several modular detachability and tip steerability features were applied to the SATA-LRS instrument platform designed specifically for LRS. Ten subjects participated a dis- and reassembly experiment to validate the modularity, and in a steering experiment using a custom made set-up to validate steering. A new steerable SATA-LRS instrument was developed with the ability to exchange end-effectors through a disassembly of the shafts. Experiments showed an average 34 and 90 s for complete dis- and reassembly, respectively. Participants were able to handle the instrument independently after a single demonstration and 4 rounds of repetitions. Precise tip-target alignment in the box set-up showed a very short learning-curve of 6 repetitions. A novel instrument platform with articulating and rotating end-effector was designed for LRS. Within a minute the SATA-LRS can be disassembled to component level for inspection, cleaning, maintenance and repair, and can be autonomously reassembled by novices after a minimal training. The modular buildup is expected to reduce purchasing and repair costs. The instrument has been shown intuitive by use without extensive training.