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arXiv · 1712.02923

SPRK: A Low-Cost Stewart Platform For Motion Study In Surgical Robotics

Vatsal Patel·Sanjay Krishnan·Aimee Goncalves·Ken Goldberg
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Abstract

To simulate body organ motion due to breathing, heart beats, or peristaltic movements, we designed a low-cost, miniaturized SPRK (Stewart Platform Research Kit) to translate and rotate phantom tissue. This platform is 20cm x 20cm x 10cm to fit in the workspace of a da Vinci Research Kit (DVRK) surgical robot and costs $250, two orders of magnitude less than a commercial Stewart platform. The platform has a range of motion of +/- 1.27 cm in translation along x, y, and z directions and has motion modes for sinusoidal motion and breathing-inspired motion. Modular platform mounts were also designed for pattern cutting and debridement experiments. The platform's positional controller has a time-constant of 0.2 seconds and the root-mean-square error is 1.22 mm, 1.07 mm, and 0.20 mm in x, y, and z directions respectively. All the details, CAD models, and control software for the platform is available at github.com/BerkeleyAutomation/sprk.

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Vatsal Patel, Sanjay Krishnan, Aimee Goncalves, Ken Goldberg. 2017-12-08. SPRK: A Low-Cost Stewart Platform For Motion Study In Surgical Robotics. https://arxiv.org/abs/1712.02923

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