Design of Launch Vehicle Flight Control Systems Using Ascent Vehicle Stability Analysis Tool
A launch vehicle represents a complicated flex-body structural environment for flight control system design. The Ascent-vehicle Stability Analysis Tool (ASAT) is developed to address the complicity in design and analysis of a launch vehicle. The design objective for the flight control system of a launch vehicle is to best follow guidance commands while robustly maintaining system stability. A constrained optimization approach takes the advantage of modern computational control techniques to simultaneously design multiple control systems in compliance with required design specs. “Tower Clearance” and “Load Relief” designs have been achieved for liftoff and max dynamic pressure flight regions, respectively, in the presence of large wind disturbances. The robustness of the flight control system designs has been verified in the frequency domain Monte Carlo analysis using ASAT.
Application of Optimization technique for Compensator design of Launcher Attitude Control
Abstract This paper deals with the compensator design of launch vehicle attitude control in atmospheric phase using optimization algorithm. Traditionally compensator design is carried out intuitively based on physical parameters of launch vehicle. It is arrived at after a long trial and error procedure to fulfil frequency domain requirements. In this paper a multi-constraint satisfaction algorithm is used to design compensator for attitude control, which takes into account the frequency and time domain requirements. The effect of actuator non-linear behavior on slosh dynamics is investigated and the analytical expression for slosh response with respect to actuator amplitude is derived. The slosh closed loop pole migration with the variation in actuator command amplitudes in root locus is discussed and the implication of acceptable actuator limit cycle amplitude on vehicle body rate is brought out.
Concentration of amino acids in wine after the end of fermentation by Saccharomyces cerevisiae strains
Both quantitative and qualitative differences in the utilization and release of assimilable nitrogen by two wine strains of Saccharomyces cerevisiae (cerevisiae and capensis) under different conditions of oxygen were observed. These differences were influenced by the presence of oxygen at the beginning of the fermentation, and by the strain of S cerevisiae. The release of some amino acids post-fermentation may be the result of reoxidation of NAD(P)H in order to maintain a normal redox balance. Copyright © 2003 Society of Chemical Industry