System and Method for Manipulating an Anatomy Letting a Surgical Robot Remove Tissue in Zones at Different Speeds

This patent describes a robot-assisted surgery system that removes tissue within carefully defined virtual zones, working faster in the bulk of the region and more cautiously near the edges. It uses virtual boundaries to control exactly where and how quickly the robot’s tool is allowed to cut.

The Problem

In procedures such as joint replacement, a surgeon needs to remove a precise amount of bone to fit an implant. A robotic system can do this with great accuracy, but speed and safety pull in opposite directions. Moving the cutting tool quickly clears material efficiently, yet near the planned border of the region, where over-cutting could damage healthy tissue, the same speed becomes risky. A system that runs at a single rate either wastes time being cautious everywhere or takes on extra risk near sensitive edges.

What This Invention Does

The system uses a surgical tool carried by a robotic manipulator and one or more controllers that define more than one virtual boundary. A first virtual boundary marks a first portion of the anatomy that may be removed, and the robot autonomously moves the tool within that boundary at a first feed rate to clear it. A second virtual boundary, spaced apart from the first, marks a further portion that may be removed, and the system handles that zone separately, allowing a different and typically more careful approach as the tool nears the final border. By splitting the region into zones with their own boundaries and feed rates, the robot can work quickly through the bulk while slowing down where precision matters most.

Key Features

• Multiple virtual boundaries. The controller defines separate boundaries delineating different portions of the anatomy to be removed.
• Zone-specific feed rates. The tool can move at one rate in the bulk region and a different rate near sensitive edges.
• Autonomous material removal. The robotic manipulator moves the tool autonomously within each defined boundary.
• Balance of speed and safety. Faster clearance in safe zones is combined with caution near critical borders.
• Built for precise bone work. The approach suits procedures that demand accurate shaping of anatomy for an implant.

Who Is Behind It

The applicant is MAKO Surgical Corp., the robotic-arm surgery business now part of Stryker and widely used in orthopaedic joint replacement. The named inventors are David Gene Bowling, John Michael Stuart, Jerry A. Culp, Donald W. Malackowski, Jose Luis Moctezuma De La Barrera, Patrick Roessler and Joel N. Beer. The application is a divisional of an earlier filing.

Why It Matters

Robotic joint replacement is one of the fastest-growing areas of surgical robotics, and efficiency in the operating room has real value without compromising the precision that drew surgeons to robotics in the first place. A method that varies cutting speed by zone helps shorten procedures while protecting healthy tissue. Securing it in Australia supports the company’s strong position in the local orthopaedic robotics market.

Related Concepts

• Robot-assisted surgery – the field this system belongs to.
• Virtual fixture – the virtual-boundary concept that constrains the tool.
• Joint replacement – a primary procedure for this kind of robotic system.
• Haptic technology – the force-feedback approach often paired with surgical boundaries.
• Orthopedic surgery – the surgical specialty most associated with this work.

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AU 2026201903 was published in the Australian Official Journal of Patents on 2 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.