Space Webs and Spider-bots: Modelling and Biomimetic Inspiration
- Paper number
IAC-07-C2.2.09
- Author
Dr. Dario Izzo, European Space Agency (ESA)/ESTEC, The Netherlands
- Coauthor
Dr. Mattias Gardsback, Sweden
- Coauthor
Dr. Gunnar Tibert, Sweden
- Coauthor
Dr. Claudio Bombardelli, Advanced Concepts Team, The Netherlands
- Coauthor
Mr. Michael Broschart, The Netherlands
- Year
2007
- Abstract
The Japanese Furoshiki experiment, in January 2006, proved the possibility to deploy a net in a microgravity environment. The experiment consisted of a triangular net stabilized by actively tensioning it using three daughter satellites attached to the triangle vertices. The measurements and results derived from this cornerstone achievement motivated a research effort to investigate numerically the stability and dynamical properties of what we call a space web: a net deployed in a microgravity environment. In this paper we will mainly focus on the centrifugal deployment of space webs and on the effect that spider-bots crawling along the web have on the overall system stability. Starting from a short overview we develop reduced degrees of freedom analytical models to qualitatively describe the dynamics of controlled, centrifugal force deployment of space webs. By comparing these models to a precise finite element model we show that the deployment dynamics of a net can be described using the same basic principles used for modelling the deployment of solid reflectors and tether systems from a rotating central satellite. With a little modification the movement of a spider-bot can also be included in the dynamical model. The deployment of the web itself can be controlled in different ways. Central hub torque, tether length, tether tension could be used as controls during the deployment. The difference between these techniques is discussed together with the instabilities induced by the movements of the robots on a deployed web. We show that if the right balance between the Coriolis forces and the centrifugal tension is maintained during the spider movement, stability can be achieved. Finally we propose a simple solution for the attaching and mobility of spider-bots on the web. We take inspiration from the locomotive and manipulative capabilities spiders are using to interact with their webs on the ground. In particular, we consider the tarsal grasping mechanism of web spiders as a possible solution to the attachment and mobility of small robots on a spinning net. The concept is discussed taking into account the environment difference between a space web and the gravity-dominated environment of a terrestrial web.
- Abstract document