Masahiko Yamazaki

A practical education of space engineering by using CanSat and pico-satellite - Fruitful collaboration with UNISEC for success of student satellite program -

This paper reports the history of the student pico-satellite program in Nihon University, especially about how a small laboratory which had no knowledge on satellite technology has succeeded the launch and operation of the student pico-satellite. The author hopes that his method would be a helpful example for supervisors who will start the student satellite program.

Low-Order Model of Spin Type Solar Sail Dynamics by Empirical Model Reduction

The paper will try to discuss the issue of reducing the time to calculate the nonlinear dynamics simulation of the gossamer structure, especially for the solar sail, because one of the problems in the gossamer structure is design time reduction. Therefore the present paper describes the low-order model of a spin type solar sail dynamics. The model reduction technique is required to shorten the design period. However there is no model reduction methodology about the solar sail dynamics. In this paper the full-order model of a spin type solar sail craft is modeled by geometrically nonlinear FEM based on the energy momentum method (EMM), so the numerical time integration is unconditionally stable. The low-order model is constructed by an empirical model reduction method. To conserve the geometrical relation of constraint conditions on the low-order space, we constructed a penalty method for the geometrical constraint based on the EMM. We will show the reduction model of the spin type solar sail model can approximate the full-order model with sufficient accuracy. Nomenclature d C = covariance matrix m i e = nodal base vector () E = expectation x m  f = modified vector of the internal force corresponding to the nodal position vector m x m   f = modified vector of the internal force corresponding to the finite rotation vector m  x m  F = modified vector of external force corresponding to the nodal position vector m x m   F = modified vector of external force corresponding to the finite rotation vector m  H = total energy i i = orthonormal vector = () 123 ,, T

Membrane Deployment de-orbit System by convex tapes

1. Deorbit Device For the purpose of re-entering a 3U size(10cm×10cm×30cm) Nano-satellite into the atmosphere, we have developed a deorbit device using a convex tape (metal tapes that have consistent curvature, represented by commercially available, steel measure tapes). The deorbit device contains a folded membrane, which is deployed by the convex tape. The deorbit device and deployment image of it are shown in Figure1 and Figure2 respectively. The various elements of the deorbit device is shown in Table1.

Development of Stereo Camera System for Accurate Observation of Large Deployable Membranes in Orbit

In this study, a stereo camera system is under development in order to measuring feature of deployable membrane in space environment in a high precision. The stereo camera system measures the condition and the behavior of the membrane. To compare the results with the design or simulations, the knowledge of the design of large structures for future missions will be shown. This system will be loaded on 3U CubeSat which will be launched in 2018. Main mission of the satellite is for demonstrating a large deployable structure. The design and BBM test results of the stereo camera system development will be discussed.

Estimation Method of Missing Components for Spin Deployable Membrane Dynamic

In recent years, there have been lots of attention in the use of membranes for large space structure applications. Typical applications include sunshields, parabolic reflectors, solar concentrators, and solar sails. In order to predict the membrane dynamics precisely, it is necessary to use the on-orbit measurement data. However, the on-orbit sail membrane measurement data are incomplete (missing spatio-temporal data) because of sensor placement limitations and sunlight reflection. This paper proposes an estimation method in which past measurement data and current incomplete measurement data are used to estimate membrane dynamics. Further, the applicability of the proposed estimation method is evaluated via microgravity experiments. The experimental model used comprises a spin deployable space membrane structure consisting of a square membrane, a center hub, and tethers.

Hands-on learning of space systems engineering by using classroom pico-satellite “HEPTA”

In this paper, the newly-developed space systems engineering education tool “classroom pico-satellite HEPTA” is introduced. The objective of this pico-satellite HEPTA kit is easy to understand space systems engineering by using low-cost component over a short amount of time. It is based on former CubeSat development experience at Nihon University, SEEDS and SPROUT. This kit can provide learning opportunity to large number of students with varied background. The minute detail of HEPTA kit of hardware & software and outline of the hands-on training is introduced in this paper.