Int. J. Mechanisms and Robotic Systems, Vol. 1, Nos. 2/3, 2013 185 Copyright © 2013 Inderscience Enterprises Ltd. A novel prism deployable mechanism based on straight-line mechanism Shengnan Lu* DIME, PMAR Robotics, University of Genoa, Genoa 16145, Italy and Robotics Institute, Beihang University, Beijing 100191, China E-mail: lvshengnan5@gmail.com *Corresponding author Dimiter Zlatanov DIME, PMAR Robotics, University of Genoa, Genoa 16145, Italy E-mail: zlatanov@dimec.unige.it Xilun Ding Robotics Institute, Beihang University, Beijing 100191, China E-mail: xlding@buaa.edu.cn Rezia Molfino DIME, PMAR Robotics, University of Genoa, Genoa 16145, Italy E-mail: molfino@dimec.unige.it Abstract: This paper proposes a novel planar deployable mechanism (PDM) based on the Hoekens straight-line linkage. The new mechanism has the property of deploying and compacting in only one dimension. The kinematics and the singularities of the PDM are analysed, and its magnification ratio is calculated as a function of the geometry of the links. Furthermore, we describe the possibility and the principles of combining multiple unit mechanisms into a larger deployable mechanism. This process allows the creation of a series of deployable mast units, which in turn are used to design a novel family of prism deployable mechanisms with one degree of freedom and invariable cross-sections.