Experimental results regarding two-dimensional deployment of inflatable beams

Inflatable technology is seen as an enabling technology for very large spacecraft because of the benefits of smaller stow-size and reduction of mass when compared with rigid-body alternatives. The experiments described in this paper were conducted with two goals in mind. First, qualitative observations and quantitative measurements were needed relating pressurization and motion in planar inflating tube deployment experiments. The second goal was to extend the verification of a simulation capability developed previously. The experiments were conducted on an air table so that two-dimensional motion could be obtained without being affected by gravity. Internal pressure was measured at the two extremities of the beam, along with the accelerations at these two points. Common characteristics were seen in the inflation of several different fold patterns, including the free and extending radially away from the freely-rotating fixed end, a general "U" shape being formed as an intermediate step, and a slight dip in the pressure of the free end as the inflatable beam becomes straight. Simulation results accurately predict global and local characteristics of the two-dimensional inflating beam deployment from different initial conditions and with different constraints at the fixed end. Efforts are continuing to correlate pressurization results from test and simulation.