title: Dimensionality Reduction in Controlling Articulated Snake Robot for Endoscopy Under Dynamic Active Constraints.
abstract: This paper presents a real-time control framework for a snake robot with hyper-kinematic redundancy under dynamic active constraints for minimally invasive surgery. A proximity query (PQ) formulation is proposed to compute the deviation of the robot motion from predefined anatomical constraints. The proposed method is generic and can be applied to any snake robot represented as a set of control vertices. The proposed PQ formulation is implemented on a graphic processing unit, allowing for fast updates over 1 kHz. We also demonstrate that the robot joint space can be characterized into lower dimensional space for smooth articulation. A novel motion parameterization scheme in polar coordinates is proposed to describe the transition of motion, thus allowing for direct manual control of the robot using standard interface devices with limited degrees of freedom. Under the proposed framework, the correct alignment between the visual and motor axes is ensured, and haptic guidance is provided to prevent excessive force applied to the tissue by the robot body. A resistance force is further incorporated to enhance smooth pursuit movement matched to the dynamic response and actuation limit of the robot. To demonstrate the practical value of the proposed platform with enhanced ergonomic control, detailed quantitative performance evaluation was conducted on a group of subjects performing simulated intraluminal and intracavity endoscopic tasks.
authors.affiliation: Hamlyn Centre for Robotic Surgery, Imperial College London, London SW7 2AZ, U.K. kkwok@imperial.ac.uk.
authors.forename: Ka-Wai
authors.initials: KW
authors.lastname: Kwok
authors.affiliation: Department of Computing, Imperial College London, London SW7 2AZ, U.K.
authors.forename: Kuen Hung
authors.initials: KH
authors.lastname: Tsoi
authors.affiliation: Hamlyn Centre for Robotic Surgery, Imperial College London, London SW7 2AZ, U.K.
authors.forename: Valentina
authors.initials: V
authors.lastname: Vitiello
authors.affiliation: Hamlyn Centre for Robotic Surgery, Imperial College London, London SW7 2AZ, U.K.
authors.forename: James
authors.initials: J
authors.lastname: Clark
authors.affiliation: Department of Computing, Imperial College London, London SW7 2AZ, U.K.
authors.forename: Gary C T
authors.initials: GC
authors.lastname: Chow
authors.affiliation: Department of Computing, Imperial College London, London SW7 2AZ, U.K.
authors.forename: Wayne
authors.initials: W
authors.lastname: Luk
authors.affiliation: Hamlyn Centre for Robotic Surgery, Imperial College London, London SW7 2AZ, U.K.
authors.forename: Guang-Zhong
authors.initials: GZ
authors.lastname: Yang
keywords: Dynamic active constraints (DACs); haptic interaction; hyper-redundant robot; proximity queries (PQs); snake robot
references.citation: Ultrasound Med Biol. 2009 Nov;35(11):1773-82
references.pmid: 19716226
references.citation: Am J Gastroenterol. 2007 Feb;102(2):261-6
references.pmid: 17156149
references.citation: Gastrointest Endosc. 2008 Apr;67(4):771-3
references.pmid: 18206880
references.citation: Ann Thorac Surg. 2009 Apr;87(4):1253-6
references.pmid: 19324161
references.citation: IEEE Trans Med Imaging. 2009 Aug;28(8):1141-55
references.pmid: 19447701
references.citation: Med Image Comput Comput Assist Interv. 2010;13(Pt 1):69-76
references.pmid: 20879216
references.citation: J Clin Gastroenterol. 2001 Mar;32(3):235-7
references.pmid: 11246352
references.citation: Med Image Comput Comput Assist Interv. 2009;12(Pt 1):410-7
references.pmid: 20426014
references.citation: Med Image Comput Comput Assist Interv. 2010;13(Pt 3):229-36
references.pmid: 20879404
references.citation: IEEE Trans Med Imaging. 2001 Feb;20(2):94-103
references.pmid: 11321594
references.citation: Endoscopy. 1992 Nov;24(9):754-8
references.pmid: 1468391
references.citation: Surg Endosc. 2008 Mar;22(3):600-4
references.pmid: 17973169
references.citation: IEEE Trans Med Imaging. 2008 Aug;27(8):1061-70
references.pmid: 18672424