1 research outputs found
Design and integration of a parallel, soft robotic end-effector for extracorporeal ultrasound
Objective: In this work we address limitations in state-of-the-art ultrasound
robots by designing and integrating a novel soft robotic system for ultrasound
imaging. It employs the inherent qualities of soft fluidic actuators to
establish safe, adaptable interaction between ultrasound probe and patient.
Methods: We acquire clinical data to determine the movement ranges and force
levels required in prenatal foetal ultrasound imaging and design the soft
robotic end-effector accordingly. We verify its mechanical characteristics,
derive and validate a kinetostatic model and demonstrate controllability and
imaging capabilities on an ultrasound phantom. Results: The soft robot exhibits
the desired stiffness characteristics and is able to reach 100% of the required
workspace when no external force is present, and 95% of the workspace when
considering its compliance. The model can accurately predict the end-effector
pose with a mean error of 1.18+/-0.29mm in position and 0.92+/-0.47deg in
orientation. The derived controller is, with an average position error of
0.39mm, able to track a target pose efficiently without and with externally
applied loads. Ultrasound images acquired with the system are of equally good
quality compared to a manual sonographer scan. Conclusion: The system is able
to withstand loads commonly applied during foetal ultrasound scans and remains
controllable with a motion range similar to manual scanning. Significance: The
proposed soft robot presents a safe, cost-effective solution to offloading
sonographers in day-to-day scanning routines. The design and modelling
paradigms are greatly generalizable and particularly suitable for designing
soft robots for physical interaction tasks