page_title: Dwell mechanism
section_title: Dwell with Linkage Mechanisms
hierarchical_section_title: Dwell mechanism / Dwell with Linkage Mechanisms
caption_attribution_description: English: Six-bar dwell linkage with translating joint - simulation done with MeKin2D
context_page_description: A dwell mechanism is an intermittent motion mechanism that alternates forward and return motion with holding position.
context_section_description: Linkage (mechanical) mechanisms can only provide approximate single dwell, and require a minimum of six links.  A Four-bar linkage mechanism must be picked first to provide the appropriate coupler curve with a circular region (or approximate circular region).  A two link dyad is then added to provide the output link with the desired dwell motion.
  The concept for linkage dwell mechanisms is that a node located at the center of the circular arc segment of a coupler curve will remain relatively stationary. Therefore, actual dwell time will depend on the length of the approximate circular arc in the coupler curve. Initial designs may need optimization to improve the dwell characteristics.
caption: Stephenson III dwell mechanism with prismatic joint. Simulation done with MeKin2D.