Incorporating new dynamic structures in ultrasonic surgical devices enabled by 3D printing titanium.

A research effort is underway to integrate miniaturised ultrasonic surgical devices with surgical robots for
minimally invasive surgeries. Current ultrasonic devices consist of a transducer, waveguide and surgical
tip and incorporate long waveguides for minimally invasive surgeries. This means that the surgical tip can
only be delivered along a straight path and the devices cannot be integrated with flexible robots. However,
a very small ultrasonic device contains only a small volume of the excitation material, which is
piezoelectric. This limits the achievable vibrational amplitude and so it is necessary to explore new dynamic
structures that can enhance the vibrational motion of the surgical tip in a small sized device.
Currently, the incorporation of internal structures in the transducers and waveguides of ultrasonic surgical
devices is limited by the capabilities of subtractive manufacturing technologies. Internal features that can
enhance the dynamic response are a potential enabler for miniaturising ultrasonic surgical devices, because
miniaturisation requires the excitation of a displacement amplitude at the surgical tip that is consistent with
much larger devices, but with a much smaller volume of piezoelectric material.
This study will therefore investigate the use of 3D printing technologies for the manufacture of the titanium
alloy (Ti-6Al4V) parts of the transducer and surgical tip. The study will consider potential internal dynamic
structures that can only be manufactured using 3D printing technologies and will investigate a range of
internal void patterns and reticulated structures to deliver enhanced vibrational performance.