The arrival of several new soft tissue robotic systems has transformed the market into one where different engineering philosophies compete to solve the same surgical problems. Interestingly, the differences between these systems are no longer limited to marketing or incremental improvements. Instead, manufacturers are making fundamentally different choices about how a surgical robot should be designed. As surgeons, understanding these concepts is probably more useful than memorizing the specifications of every platform.
There is no universally “correct” solution. Every design represents a compromise between stability, flexibility, cost, operating room logistics, and surgeon experience. Nevertheless, some clear categories have emerged. Let´s go through them.
The first major distinction concerns the patient-side cart (the actual robot). The integrated patient-side cart is the architecture introduced by the original da Vinci systems and later adopted by several newer platforms. Multiple robotic arms are mounted on a single cart positioned next to the patient. This is Intuitive´s da Vinci Xi, da Vinci 5, and da Vinci SP, hinotori, Toumai, Shurui… The relative position of every arm is fixed during manufacturing, allowing highly predictable geometry, simplified docking, and excellent mechanical rigidity. Once positioned, the system behaves as a single coordinated machine.
Independent modular arms (split modules) is a different philosophy represented by systems such as CMR Versius and Medtronic Hugo RAS. Instead of one large robot, each robotic arm is an independent module that can be positioned individually around the patient. This offers tremendous flexibility. The operating room team can optimise arm placement for different procedures and specialties, potentially improving access in complex cases or crowded theatres. However, that flexibility comes at a price. Every arm must be positioned individually, requiring more decisions during setup. Docking may therefore take longer, and maintaining ideal geometry depends more heavily on the experience of the surgical team. As an added value the surgeon can choose how many arms to use. Neither approach is inherently superior. One prioritises simplicity and rigidity; the other prioritises adaptability.
Multiport versus single-port surgery. This distinction is often misunderstood. The critical difference is not the number of robotic arms but the number of access ports entering the patient. Multiport systems remain the standard approach. Each robotic instrument enters through its own trocar or cannula, allowing excellent triangulation and freedom of movement (da Vinci Xi and da Vinci 5, Versius, Hugo, hinotori, Toumai…). This approach works extremely well for abdominal, thoracic and pelvic surgery.
Single-port systems is a different concept represented by da Vinci SP and Shurui platform. Here, the camera and all instruments pass through a single cannula before articulating inside the body. This changes the entire surgical geometry. Instead of triangulating outside the patient, triangulation occurs internally after the instruments emerge from the common access port. For natural orifice surgery, including transoral robotic surgery (TORS), this offers important theoretical and practical advantages. Instrument crowding outside the patient is reduced, collisions become less problematic, and access through confined anatomical corridors becomes considerably easier.
As a Head&Neck surgeon, I believe this remains one of the most important developments in robotic surgery. The single-port concept appears particularly well suited to the anatomy of the upper aerodigestive tract.
Instrument support: supported shafts versus unsupported instruments This is perhaps one of the least discussed, but mechanically most important design choices. Platforms such as the da Vinci family, Hugo and hinotori guide each instrument through a rigid cannula that supports the shaft close to the patient. The cannula acts as a stabilising structure. Only the distal portion of the instrument needs to move freely, while the shaft remains mechanically constrained. This provides excellent precision and minimises unwanted movement caused by long unsupported instrument shafts.
Systems such as Versius and hinotori follow a different philosophy. The instruments are not constrained by a distal support cannula. Instead, much longer instrument shafts extend freely from the robotic arm to the patient. This increases flexibility and reduces the amount of hardware at the operative field. However, it also creates a greater engineering challenge. Long unsupported instruments are inherently more susceptible to vibration and elastic deflection, particularly when forces are applied to tissue. However, this is an option. Percutaneous approaches will still need a cannula (conventional non-robotic cannulas can be used).
Immersive visor or open console? The surgeon’s experience is shaped not only by the robot but also by the console. Two distinct philosophies have emerged.
Immersive viewer (da Vinci, hinotori, Toumai) place the surgeon inside a stereoscopic viewer. The surgeon is visually isolated from the operating room, seeing only the operative field. The advantages are immediately apparent. The experience is highly immersive, depth perception is excellent, distractions are minimised, and many surgeons report that they rapidly “forget” they are operating through a machine. For many of us, this remains one of the defining characteristics of robotic surgery.
Open console (Versius, Hugo…) allow the surgeon to operate while looking at an open 3D monitor. The surgeon maintains direct visual contact with the operating room team throughout the procedure. This improves communication and situational awareness, while also reducing the physical enclosure associated with visor-based consoles. Whether this represents an advantage depends largely on personal preference. Some surgeons may appreciate the openness of these systems.
Is one philosophy better? Probably not. Each manufacturer has optimised its platform for different priorities. Some favour operating room flexibility. Others prioritise mechanical precision. Some seek ergonomic openness. Others maximise visual immersion. As robotic surgery becomes increasingly competitive, diversity of design should be welcomed. Different procedures, and different surgeons, may ultimately favour different solutions.
Personally, I continue to favour immersive visor-based consoles because they provide an unmatched sense of presence within the operative field. I also believe that distal instrument support still offers superior mechanical stability, particularly during delicate dissection. Finally, as a head and neck surgeon, I remain convinced that the future of transoral robotic surgery lies in true single-port platforms. The anatomy we work in is narrow, crowded and unforgiving, making internal triangulation through a single access channel an elegant solution to a uniquely challenging surgical environment.
We keep moving forward.
J Granell. Jul 9, 2026.
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