60 IEEE ROBOTICS & AUTOMATION MAGAZINE SEPTEMBER 2013 1070-9932/13/$31.00©2013IEEE n this article, we present a robot capable of autonomously traversing and manipulating a three-dimensional (3-D) truss structure. The robot can approach and traverse multiple structural joints using a combination of translational and rotational motions. A key factor in allowing reliable motion and engagement is the use of specially designed structural building blocks comprised of bidirectional geared rods. A set of traversal plans, each comprised of basic motion primitives, were analyzed for speed, robustness, and repeatability. Paths covering eight joints are demonstrated, as well as automatic element assembly and disassembly. We suggest that the robot architecture and truss module design, such as the one presented here, could open the door to robotically assembled, maintained, and reconfigured structures that would ordinarily be difficult, risky, or time consuming for humans to construct. Design of Robot Structure-climbing robots have traditionally been devel- oped to perform tasks currently carried out by humans, which range from structural inspections to cleaning and maintenance. Our goal in this article is to explore both robot and structure design to expand the range of tasks which can be successfully completed autonomously. Spe- cifically, we are interested in the design of a robot capable of modifying a structure by taking it apart and rebuilding it into a different shapes. Such structure-reconfiguring robots could have a profound impact on construction processes, especially activities involving frame construc- tion. In the longer term, the ability to autonomously Digital Object Identifier 10.1109/MRA.2012.2201579 By Franz Nigl, Shuguang Li, Jeremy E. Blum, and Hod Lipson Date of publication: 21 June 2013 Autonomous Truss Reconfiguration and Manipulation © ISTOCKPHOTO.COM/RADIST777 I