Empirically Bounding of Space Booms with Tape Spring Hinges

Abstract

Self-deploying structures seek to provide a compact launch package for large, lightweight satellite booms. One self-deploying method is a foldable tape spring. This paper examines the large scale behavior of a boom attached by a tape spring hinge during mock deployments. A boom attached by tape spring to a rigid stand was released and the boom bounced up to 60° before coming to rest (as opposed to snap-through behavior). These large amplitude bounces can cause the boom to collide with sensors, other booms or arrays causing damage or preventing full deployment. Results show the first bounce of deployment is nearly bounded by a four parameter ellipse. The ellipses of similar folds are similar also, suggesting that a model can be developed. Free-fall tests simulating the free-free condition found in microgravity also show similar elliptical motion. Envelopes that bound the extents of the boom motion allow for collisions to be prevented by adjustment of the design.

Spatial Mapping of Protein Adsorption on Mesoporous Silica Nanoparticles by Stochastic Optical Reconstruction Microscopy

“…To address these issues, individual particles were selected for analysis and all molecules associated with their respective particles were extracted as Cartesian coordinates from the STORM data set for each fluorophore. For a given particle, protein coordinates were used to calculate the sphere of best fit, by minimizing the function: Here, I = the number of data points; ( x i , y i , z i ) = the i th measurement of the origin; ( x c , y c , z c ) = the center of the sphere; and r c = the radius of the sphere. An example of the processing method is shown in Figure S4 for apolipoprotein A-II adsorbed onto small pore MSN.…”