Examining the accuracy of Space Shuttle support loads using probabilistic analysis techniques
Abstract
To understand unexpectedly erratic load measurements in the launch pad supports for the Space Shuttle, the sensitivities of the load cells in the supports were analyzed using simple probabilistic techniques. NASA engineers use the loads in the Shuttle's supports to calculate critical stresses in the Shuttle vehicle just before liftoff. The support loads are measured with 'load cells', which actually are structural components of the mobile launch platform that have been instrumented with strain gauges. Although these load cells adequately measure vertical loads, horizontal load measurements have been erratic. Load measurements were simulated in this study using Monte Carlo simulation procedures. The simulation studies showed that the support loads are sensitive to small deviations in strain and calibration. In their current configuration, the load cells will not measure loads with sufficient accuracy to reliably calculate stresses in the Shuttle vehicle.
- Publication:
-
Journal of Spacecraft and Rockets
- Pub Date:
- September 1994
- DOI:
- 10.2514/3.26517
- Bibcode:
- 1994JSpRo..31..814R
- Keywords:
-
- Aerospace Engineering;
- Critical Loading;
- Launching Bases;
- Liftoff (Launching);
- Mathematical Models;
- Monte Carlo Method;
- Prediction Analysis Techniques;
- Probability Theory;
- Space Shuttles;
- Stress Analysis;
- Support Systems;
- Calibrating;
- Computerized Simulation;
- Horizontal Distribution;
- Sensitivity;
- Strain Gages;
- Stress Measurement;
- Structural Design;
- Vertical Distribution;
- Space Transportation