0
Technical Brief

Design of a Spatial RPR-2SS Valve Mechanism

[+] Author and Article Information
Peter L. Wang

Robotics and Automation Laboratory,
University of California,
Irvine, CA 92697
e-mail: wangpl1@uci.edu

Ulrich Rhem

Dr. Rehm Tunnelling Consultant GmbH,
Lotzbeckstr., 25, D-77933,
Lahr 77933, Germany
e-mail: ru@tunnelling-consultant.de

J. Michael McCarthy

Robotics and Automation Laboratory,
University of California,
Irvine, CA 92697
e-mail: jmmccart@uci.edu

Contributed by the Mechanisms and Robotics Committee of ASME for publication in the JOURNAL OF MECHANISMS AND ROBOTICS. Manuscript received November 1, 2017; final manuscript received March 23, 2018; published online May 31, 2018. Assoc. Editor: Marc Gouttefarde.

J. Mechanisms Robotics 10(4), 044504 (May 31, 2018) (7 pages) Paper No: JMR-17-1376; doi: 10.1115/1.4040027 History: Received November 01, 2017; Revised March 23, 2018

This paper applies kinematic synthesis theory to obtain the dimensions of a constrained spatial serial chain for a valve mechanism that cleans and closes a soil conditioning port in a tunnel boring machine. The goal is a smooth movement that rotates a cylindrical array of studs into position and then translates it forward to clean and close the port. The movement of the valve is defined by six positions of the revolute-prismatic-revolute (RPR) serial chain. These six positions are used to compute the dimensions of the two spherical spherical (SS) dyads that constrain the RPR chain to obtain a one degree-of-freedom spatial mechanism. An example design of this valve mechanism is provided in detail.

FIGURES IN THIS ARTICLE
<>
Copyright © 2018 by ASME
Topics: Chain , Design , Valves , Soil , Linkages , Rotation
Your Session has timed out. Please sign back in to continue.

References

EFNARC, 2005, Specification and Guidelines for the Use of Specialist Products for Mechanised Tunnelling (TBM) in Soft Ground and Hard Rock, EFNARC, Farnham, UK.
Thewes, M. , 1999, “ Adhasion Von Tonböden Beim Tunnelvortrieb Mit Flüssigkeitsschilden [Adhesion of Clay Soil During Tunneling With Liquid Shields],” Ph.D. thesis, Universitaet Wuppertal, Wuppertal, Germany.
Rehm, U. , 2004, “ Maschineller Tunnelvortrieb Unter Sehr Schwierigen Geologischen Verhältnissen,” Tunnel-Tiefbautagung Gyoer, p. 99.
Jancsecz, S. , Krause, R. , Langmaack, L. , 1999, “ Advantages of Soil Conditioning in Shield Tunnelling: Experiences of Lrts Izmir,” Challenges for the 21st Century, pp. 865–875.
Rao, A. M. , Sandor, G. N. , Kohli, D. , and Soni, A. , 1973, “ Closed Form Synthesis of Spatial Function Generating Mechanism for the Maximum Number of Precision Points,” ASME J. Eng. Ind., 95(3), pp. 725–736. [CrossRef]
Cervantes-Sanchez, J. J. , Gracia, L. , Alba-Ruiz, E. , and Rico, M. J. M. , 2011, “ Synthesis of a Special Rpspr Spatial Linkage Function Generator for Six Precision Points,” Mech. Mach. Theory, 46(2), pp. 83–96. [CrossRef]
Cervantes-Sanchez, J. J. , Rico-Martinez, J. M. , Perez-Munoz, V. H. , and Bitangilagy, A. , 2014, “ Function Generation With the Rrrcr Spatial Linkage,” Mech. Mach. Theory, 74, pp. 58–81. [CrossRef]
Chen, P. , and Roth, B. , 1969, “ Design Equations for Finitely and Infinitesimally Separated Position Synthesis Position Synthesis of Binary Links and Combined Link Chains,” ASME J. Eng. Ind., 91(1), pp. 209--219.
McCarthy, J. M. , and Soh, G. S. , 2010, Geometric Design of Linkages, Vol. 11, Springer Science & Business Media, New York.
Sandor, G. N. , Xu, L. J. , and Yang, S. P. , 1986, “ Computer-Aided Synthesis of Two-Closed-Loop Rssr-Ss Spatial Motion Generator Wbranching and Sequence Constraints,” Mech. Mach. Theory, 21(4), pp. 345–350. [CrossRef]
Chiang, C. H. , Yang, Y.-N. , and Chieng, W. H. , 1994, “ Four-Position Synthesis for Spatial Mechanisms With Two Independent Loops,” Mech. Mach. Theory, 29(2), pp. 265–279. [CrossRef]
Chung, W.-Y. , 2015, “ Synthesis of Spatial Mechanism Ur-2ss for Path Generation,” ASME J. Mech. Rob., 7(4), p. 041009.
Wang, P. L. , Taha, H. E. , and McCarthy, J. M. , 2018, “ Synthesis of a Flapping Wing Mechanism Using a Constrained Spatial Rrr Serial Chain,” ASME J. Mech. Rob., 10(1), p. 011005.
Innocenti, C. , 1995, “ Polynomial Solution of the Spatial Burmester Problem,” ASME J. Mech. Des., 117(1), pp. 64–68. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Photograph of a tunnel boring machine cutter with arrows identifying the soil conditioning ports

Grahic Jump Location
Fig. 2

The spatial RPR-2SS linkage constructed by constraining a spatial RPR serial chain using two SS dyads that connect the second and third links to the ground frame

Grahic Jump Location
Fig. 3

The mechanism is mounted inside a T pipe that has one end capped. Flow enters at the bottom left and exits at the top left.

Grahic Jump Location
Fig. 4

When the valve closes, it also plunges grate as a self-cleaning action. The studs of the plunger can be seen during the extension phase.

Grahic Jump Location
Fig. 5

The link OA of the RPR-2SS linkage is held fixed. Points C and F are connected to a single crank which drive links ABD and DE.

Grahic Jump Location
Fig. 6

The desired slide and rotation function and the respective precision points are shown. The precision points have been adjusted from the curves during design process.

Grahic Jump Location
Fig. 10

This figure shows mechanism with the sealing drum transparent and the pipe hidden. The plunging studs are now visible through the sealing drum.

Grahic Jump Location
Fig. 11

The process involves adjustment of the precision points within user defined tolerance zones to find successful designs. Iteration of this procedure produces a large number of design candidates.

Grahic Jump Location
Fig. 7

The movement of the plunger slide with link BC and sealing rotation with link EF

Grahic Jump Location
Fig. 8

The valve is in the process of opening

Grahic Jump Location
Fig. 9

The fluid pressure inside of the pipe has decreased below the desired thresh hold, so the mechanism cleans and seals the port

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In