Evaluation of Membrane Dynamics of IKAROS based on Flight Result and Simulation using Multi-Particle Model

Abstract

Japan Exploration Agency (JAXA) launched a powered solar sail “Interplanetary Kite-craft Accelerated by Radiation Of the Sun (IKAROS)” on May 21, 2010. One of the primal technologies demonstrated at IKAROS is the spin-deployment of the sail whose diameter is 20 m class. After the launch, two-step deployment operation was performed and successful expansion of the sail was confirmed. This paper shows the flight data and observed dynamic motion during the deployment. At the quasi-static first stage deployment, the spin rate of main body shows little oscillation after each step and then damped quickly. The damping ratio of the spin rate after a later step of deployment is estimated by curve-fitting to be 0.0127. At the dynamic second stage deployment, the nutation motion is maintained within ±1.5 deg/s and the spin rate of main body is converged quickly about 60s after the deployment start. These flight result and observed dynamic motion during the deployment are compared with the results of numerical simulations using multi-particle model. These results show that the multi-particle model can simulate the global behavior of membrane sufficiently except the dumping motion of in-plane oscillation between the main body and the expanded membrane.