Analysis of the motion mode change of a metamorphic 8R linkage

TY - JOUR

T1 - Analysis of the motion mode change of a metamorphic 8R linkage

AU - Müller, A.

AU - Zhang, K.

AU - Dai, J. S.

PY - 2016

Y1 - 2016

N2 - By definition, metamorphic mechanisms can change their mobility. This change can be achieved by actively locking certain elements, or can be due to the inherent kinematics of the linkage. In the latter case the mobility is altered when passing through configuration space singularities. In a recent development, these two phenomena are combined. As such it was shown that a single-loop 8R linkage, possessing certain symmetry, turns into an overconstrained 6R linkage by only locking one joint while another joint is then implicitly constrained. This phenomenon has been analyzed by means of a first-order analysis in terms of instantaneous joint screw system. Thereupon the metamorphism was concluded and verified experimentally. An analytic proof was not yet provided. In this paper finite kinematics of the metamorphic 8R linkage is established and its ability to change to a 6R linkage by means of locking only one joint is shown analytically. The presented methodology is general and applicable to arbitrary mechanisms. It does provides a basis for the analysis and eventually the synthesis of novel metamorphic mechanisms.

AB - By definition, metamorphic mechanisms can change their mobility. This change can be achieved by actively locking certain elements, or can be due to the inherent kinematics of the linkage. In the latter case the mobility is altered when passing through configuration space singularities. In a recent development, these two phenomena are combined. As such it was shown that a single-loop 8R linkage, possessing certain symmetry, turns into an overconstrained 6R linkage by only locking one joint while another joint is then implicitly constrained. This phenomenon has been analyzed by means of a first-order analysis in terms of instantaneous joint screw system. Thereupon the metamorphism was concluded and verified experimentally. An analytic proof was not yet provided. In this paper finite kinematics of the metamorphic 8R linkage is established and its ability to change to a 6R linkage by means of locking only one joint is shown analytically. The presented methodology is general and applicable to arbitrary mechanisms. It does provides a basis for the analysis and eventually the synthesis of novel metamorphic mechanisms.

UR - http://www.scopus.com/inward/record.url?scp=84948417655&partnerID=8YFLogxK

U2 - 10.1007/978-3-319-23327-7_4

DO - 10.1007/978-3-319-23327-7_4

M3 - Conference paper

AN - SCOPUS:84948417655

SN - 2211-0992

VL - 36

SP - 39

EP - 47

JO - Mechanisms and Machine Science

JF - Mechanisms and Machine Science

ER -