Slider-crank mechanisms are widely used in reciprocating machinery, where transformation from rotational into translational motion (or vice versa) is required. Moreover, the use of these mechanisms is quite common in robotic and mechatronic systems when complex motions are to be produced with rotational actuators. However, the velocity ratio of the slider-crank mechanism is configuration-dependent and thus, elaborate algorithms are required to precisely control its performance. / In this thesis, a planar cam mechanism with an oscillating follower is proposed as a device that renders the velocity ratio of the slider-crank mechanism constant, an operation that is termed here velocity-ratio rectification ; it is expected that the rectification will ease the feedback control of the slider-crank mechanism in mechatronic applications. A methodology for the optimization of this mechanism is developed. First, the performance of the slider-crank mechanism is analyzed and optimum geometric parameters are obtained. Then, an expression for the input-output relation of the cam mechanism at hand is derived, and the corresponding displacement program of the follower is produced. In addition, an approach for the optimization of planar cam mechanisms with an oscillating follower is introduced, to minimize the overall size, while maintaining an acceptable force-transmission performance based on bounds on the pressure angle. A Graphical User Interface (GUI) is developed to allow for the above-mentioned optimization in an interactive mode; the GUI is successfully used in an example of the design of a reducer-rectifier cam mechanism that rectifies the velocity ratio of the actuator of a robotic quadruped.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.21316 |
| Date | January 1999 |
| Creators | Navarro-Martínez, Oscar R. |
| Contributors | Angeles, Jorge (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Engineering (Department of Mechanical Engineering.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001658085, proquestno: MQ50645, Theses scanned by UMI/ProQuest. |
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