@article{oai:oist.repo.nii.ac.jp:00002776,
 author = {Schönke, Johannes and Conde, Martín Forsberg and Fried, Eliot},
 journal = {Mechanism and Machine Theory},
 month = {May},
 note = {Kinematic chains made from links whose lengths and twist angles satisfy a certain proportionality rule are considered. A notion of exchange symmetry for the links of any such chain affords a new understanding of the mobility of well-known overconstrained mechanisms, exemplified by Bennett’s four-bar linkage, and provides a unifying framework for explaining the mobility of a recently discovered class of nontrivial underconstrained mechanisms. These findings allow for the design of mechanisms consisting of links that can be arbitrarily reordered without altering their number of internal degrees of freedom and, thus, of modular mechanical systems that can be assembled in different ways to serve different purposes. A nine-hinged linkage that can be assembled in ninety-four distinct ways, each evincing a single internal degree of freedom, is presented as an example of such a modular system.},
 title = {Kinematic chains with preserved mobility for arbitrary arrangements of their links},
 volume = {175},
 year = {2022}
}