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One of the most important design factors in modern turbomachinery is the vibration of turbomachinery blading. There is a need for developing an in-service, noncontacting, noninterfering method for the measurement and monitoring of gas turbine, jet engine, and steam turbine blade vibrations and stresses. Such a technique would also be useful for monitoring rotating helicopter blades. In the power generation industry, blade failures can result in millions of dollars of downtime. The measurement of blade vibrations and dynamic stresses is an important guide for preventive maintenance, which can be a major contributor to the availability of steam turbine, gas turbine, and helicopter operations, An experiment is designed to verify the feasibility of such a vibration monitoring system using the reference beam on-axis laser-Doppler technique. The experimental setup consists of two flat, cantilever blades mounted on a hub attached to the shaft of a dc motor. The motor rests on a linear bearing permitting motion only in the direction of the motor shaft. The motor and blade assembly is then excited via an electrodynamic shaker at the first natural frequency of the blades. The resulting blade vibration is then detected using a laser vibrometer. The vibration frequencies and amplitudes of the two rotating blades are successfully measured.

The dynamic equations for the simulation of Space Station Freedom configured with solar dynamic (SD) power modules are developed. The formulation permits the structure to be subjected to shuttle docking disturbances while being controlled with a 'natural' vibration and tracking control approach. Multiple control cases can be performed for the purpose of investigating the relationship between actuator effort, SD pointing, and thermal loading on the receiver aperture plate. Transient, one-dimensional heat transfer equations are formulated to conservatively predict temperatures of the multilayered receiver aperture plate assembly and thermal stresses in its shield layer. Numerical results from these analyses are presented in a companion paper (Part II).

The analytical approaches developed in a companion paper were used to quantify the relationship between fine-pointing control and thermal loading of the aperture plate. Dynamic simulations of Space Station Freedom configured with solar dynamic (SD) power modules were performed. The structure was subjected to shuttle docking disturbances, while being controlled with a 'natural' vibration and tracking control approach. Three control cases were investigated for the purpose of investigating the relationship between actuator effort, SD pointing, and thermal loading on the receiver aperture plate. Transient one-dimensional heat transfer analyses were performed to conservatively predict temperatures of the multilayered receiver aperture plate assembly and thermal stresses in its shield layer. Results indicate that the proposed aperture plate is tolerant of concentrated flux impingement during short-lived structural disturbances. Pointing requirements may be loosened and the required control torques lessened from that previously specified. Downsizing and simplifying the joint drive system should result in a considerable savings in mass.