A method to generate stable, collision free configurations for tensegrity based robots

Abstract

Abstract-Tensegrity structures appeared in the science community about half a century ago, but they have already been applied to several heterogeneous research fields, such as architecture, civil engineering, space and even biology. Such structures keep a stable volume in space due to an intricate balance of forces between a disjoint set of rigid elements (bars) and a continuous set of tensile elements (cables).The use of tensegrity structures in robotics is still new and there exist only a handful of works about this subject. Some of their main features such as light weight, flexibility, energetic efficiency and redundancy, make them interesting candidates for both mobile robots and manipulators. In this paper, a new method to detect and avoid both internal collisions between the structure members and external collisions with the environment is presented. In this way, we are providing a fundamental tool to develop more complete form-finding procedures and pathplanning strategies for tensegrity structures.

On the synthesis of feasible and prehensile robotic grasps

“…Recent research works have already started to merge some of the mentioned problems [22]- [25], however, they either miss some of the necessary constraints, limit the approach to planar grasps, or use a reduced number of fingers. A similar problematic is found as well on the synthesis of stable configurations of tensegrities [26].…”

Path planning for active tensegrity structures

“…The CuikSuite also includes a MATLAB implementation of the form-finding procedure described in (Hernández-Juan and Mirats-Tur, 2008). This procedure is particularly well-suited for path planning purposes since, in contrast to other approaches, it can take into account (self-)collisions and it can fix the pose of some of the elements of the structure (e.g., the pose of the upper triangle in the structure shown in Fig.…”

“…No symmetry is considered and, thus, the equilibrium manifold is of high dimension. Therefore, this example is used to illustrate the scalability of the approach with respect to the test-cases used in previous path planners for tensegrity structures (Hernández-Juan and Mirats-Tur, 2008;Xu et al, 2014). As a reference, none of these existing approaches have been proven to be effective in equilibrium manifolds of dimension higher than 3.…”

“…Thus, this paper extends the AtlasRRT planner to deal with these latter constraints too. Up to our knowledge, the only approaches proposing RRT planners for tensegrity frameworks are (Hernández-Juan and Mirats-Tur, 2008) and (Xu et al, 2014). Both approaches use computationally expensive form-finding procedures to generate samples and to connect them.…”

Output-Only Modal Identification of Tensegrity Structures

“…In aerospace technology, the tensegrity concept offers an alternative solution to design lightweight deployable structures as masts, solar arrays and antennas (Puig et al 2010). The tensegrity paradigm has also inspired research on string-driven robotic systems (Graells Rovira, Mirats Tur 2009;Juan, Mirats Tur 2008;Paul et al 2006). Architects are investigating responsive architecture and use of tensegrity systems in adaptive buildings (d'Estrée Sterk 2003).…”