Robots are revolutionizing the field of medicine. From critical procedures to routine tasks, physicians and hospitals are adopting the use of this advanced technology to reduce costs, enhance precision, and increase safety. The use of Robotic Magnetic Navigation (RMN) in electro-physiology was introduced a decade ago and continues to evolve. One surgical robot company, St. Louis–based Stereotaxis, recently received FDA approval for its Genesis RMN system. Stereotaxis is a global leader in innovative robotic technologies designed to enhance the treatment of arrhythmias and perform endovascular procedures. The Genesis is the first system to treat cardiac arrhythmias.
The innovative Genesis system offers the proven benefits of RMN in a design that is faster, smaller, lighter, and more flexible. The system consists of two robotically controlled magnets positioned on flexible and rugged robotic arms that are located next to the operating table. During the procedure, a physician uses a computer interface to adjust the magnetic field around the patient, directing and steering the magnetic catheter inside of the patient with extreme precision. The system’s small size improves the patient experience while on the operating table and provides medical personnel with greater access to the patient during the procedure.
Committed to optimizing overall operating performance of the machine and providing an enhanced experience for the patient, Stereotaxis initiated an assessment of the Genesis. THK, a linear motion component supplier to Stereotaxis, analyzed and identified linear motion components that could be replaced by dropping in the THK component and eliminating any need for a redesign of the Genesis.
THK experienced sales and design engineers collaborated to make determinations and validate their findings. A roller bearing inside the robotic arms of the machine was replaced with a THK Type RB cross roller ring. Data indicated that the Type RB offers increased accuracy, the ability to bear heavier loads, and improved rigidity. This upgrade resulted in a more robust design with a greatly enhanced life expectancy compared to the original bearing. The Type RB features inner ring rotation. The outer ring is separable while the inner ring is integrated with main body.
On the linear axis of the machine, THK suggested replacing the current component with the THK Type SHS25 linear motion guide. The Type SHS utilizes patented THK Caged Ball technology that eliminates friction between balls, achieves low noise, offers long-term maintenance-free operation, and provides a high-speed response. The Type SHS also features four-way equal load. The Type SHS LM block can receive a well-balanced preload, increasing the rigidity in the four directions (radial, reverse-radial, and lateral directions) while maintaining a constant, low friction coefficient. With the low sectional height and the high rigidity design of the LM block, the Type SHS achieves highly accurate and stable linear motion.
A third component, the THK Type BNT precision ground ball screw was recommended as a replacement. The Type BNT is a high-efficiency feed screw with the ball making a rolling motion between the screw axis and the nut. Compared with a conventional sliding screw, this product has drive-torque of one-third or less, resulting in drive motor power savings. Mounting screw holes are drilled on the square ball screw nut of the Type BNT, allowing it to be compactly mounted on a machine without a housing.
Having successfully incorporated THK into other designs, Stereotaxis was confident that these components would not only bring longer life and higher accuracy to its design, but most importantly, they would help to provide a superior experience for patients being treated in hospitals and clinics with Stereotaxis Genesis technology. A key advantage to using THK components in the Genesis was that THK was able to provide improved solutions using components that fit into the existing design, rather than requiring Stereotaxis to go back to the drawing board and spend valuable resources on an already proven design.