Fourteen low-methoxyl pectins were used to prepare a 30% sucrose gel with a final pectin concentration of 0.8% and an added calcium content of 25 mg Ca"/gpectin. The texture of each gel was evaluated using three descriptors: firmness, coarseness, and graininess. The relaxation behavior of the 14 gels, under a constant strain, was monitored using an Instron universal testing machine. The data were best defined by an equation that is represented by two Maxwell bodies in parallel. The elastic moduli and relaxation times o f this model ranged, between gels, f r o m 2881 Pa to 5487 Pa and from 4.1 s to 908 s, respectively. A n apparatus constructed in this laboratory was used t o measure the creep behavior of the gels under constant stress. The normal creep behavior o f the 14 gels was best defined by the Burger's Model. The elastic moduli and viscous constants of this model ranged, between gels, from 3937 Pa to 15,342 Pa and from 20,300 P1 to 40,100 P1, respectively. The relaxation modulus, E , , was the most sensitive f o r distinguishing significant differences between the gels. Several significant correlations were found between rheological, ch e m ica 1 and t e x t u ral param e ters. '

Most smart projectile control systems generate lateral control forces to guide the round to a target. Experience has shown that under the right combination of body orientation, translational velocity, and angular velocity, relatively low lateral control force inputs can induce instability of the round. To solve this problem, an additional control logic layer is appended to a nominal impact point flight control law to protect it from instability in these infrequent, but consequential situations. To highlight the newly developed control logic, a smart 155 mm spin-stabilized projectile equipped with a rotating paddle control mechanism is considered. For this example configuration, cross range maneuvering occasionally induces instability. Simulation results, using both rigid and multi-body nonlinear flight dynamics models, indicate that the addition of the instability protection layer in the control logic prevents projectile instability while not substantially altering target impact statistics. The nature of this protector design lends itself well to the use of a GPU to perform the calculations, greatly decreasing the computation time needed.

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Fourteen ammonia‐demethylated low‐methoxyl pectins were chemically defined. Each was used to prepare a 30% sucrose gel. The texture of each gel was evaluated by an eight member, semi‐trained sensory panel. Each gel was also subjected to dynamic uniaxial loading at seven frequencies ranging from 100 Hz to 280 Hz. Rheological response was found to be highly dependent on test frequency, and a resonance dispersion effect was revealed at several frequencies. The frequency that exhibited the greatest resonance dispersion was also the most sensitive in distinguishing between the 14 gels, based on absolute modulus. Ninety‐two percent of the total variation in absolute modulus could be significantly explained by the chemical composition of the pectin. Significant correlations were found between the sensory descriptors and the rheological parameters calculated from the dynamic tests.