# On the Control and Validation of the PARA-SILSROB Surgical Parallel Robot
###### Abstract
The initial version of the da Vinci robot could manage up to four surgical instruments, including three active instruments and one laparoscopic camera. Its design featured four arms mounted on a console, and it was operated using the master-slave concept [19; 20]. Additionally, this period saw the introduction of telerobotic surgery. The evolution of the da Vinci robots, alongside the improvements made to each structure, is illustrated in Figure 2[21; 22; 23; 24; 25]. Although Intuitive Surgical currently dominates the market, the first significant competitor to the da Vinci system emerged in 2018 with the Senhance robot, which was developed by Asensus Surgical [26]. That same year, Intuitive Surgical received FDA approval for the da Vinci SP, which was the first robot dedicated to single-incision laparoscopic surgery (SILS) [27]. Figure 1: The evolution of surgery from classical surgery to single-incision laparoscopic surgery [15]. Several other surgical robots are currently in development, as detailed in sources [28; 29; 30; 31]. These include the Avatera, Bitrack, Hugo RAS System, Versius, Dexter, PARAMIS, Vicarious Surgical Robotic System, PARASURG 9M, and Hominis Surgical System. These systems offer significant advantages over manual methods, thus greatly enhancing patient's safety and the quality of surgical care. The benefits include eliminating the surgeon's hand tremor, achieving increased precision, significantly improving surgeon ergonomics, eliminating the triangulation effect [32], scaling the surgeon's hand movements, increasing the dexterity, simultaneously manipulating multiple instruments, and providing a 3D visualization of the surgical field with the option to use the firefly fluorescence imaging mode [33; 34]. The primary disadvantages of these systems include high acquisition and operational costs, a steep learning curve for surgeons, potential collisions between robotic arms, limited workspace for instruments, extended setup and retrieval times in emergencies, and the lack of tactile feedback. The Senhance robot addresses some of these issues [33; 34]. These robots are employed in various surgical procedures, including appendectomy, colectomy, cholecystectomy, gastric bypass, hernia repair, hysterectomy, pancereectomy, and hepatectomy. Recent studies [35; 36; 37; 38] demonstrated the use of robots with the SILS technique in complex surgeries, such as esophagectomy for esophageal cancer. These studies emphasized the role of robots in both the resection and reconstruction times of this surgical intervention by significantly reducing the patient's trauma compared with the traditional methods [39]. Given the high difficulty and complexity of esophagus resection and reconstruction, along with the limited number of robotic systems available for such procedures, ongoing research and the development of new robotic systems and new techniques used to generate the path are essential for improved results in this field. The authors introduce several techniques for optimizing trajectory planning by utilizing neuro-fuzzy interference systems and redundant manipulators [40; 41]. The current work presents the PARA-SILSROB parallel robot, which was developed for single-incision laparoscopic surgery, where its control system and initial laboratory experimental tests were used in the first phase of the Ivor-Lewis esophagectomy procedure [42]. PARA-SILSROB offers significant advantages over current solutions, particularly the da Vinci SP, including enhanced stiffness in both the mobile platform (which supports the active instruments) and the surgical instruments themselves, as well as improved ergonomics, which makes it easier to mount and dismount the active instruments. In comparison with the Senhance, PARA-SILSROB utilizes a single mobile platform that houses the active instruments, which results in a more compact design and a reduced footprint in the operating room. Figure 2: The evolution of the da Vinci robot [25].