Noncontacting Laser Vibrometer for Six Degrees of Freedom Positional Measurement

The objective of this research is to develop a noncontacting system for the complete dynamic measurement of all six degrees of freedom of position and attitude of miniature mechanical components. This information is generally not obtainable, yet it is essential in many new engineering applications. The system is based on monitoring three laser beams reflected from a small reflective target on the component. By utilizing the geometric origin of the beams and the position of the respective reflections, all six degrees of freedom of position of the target can be determined. The research will optimize the geometry of the lasers, targets, and sensors in order to achieve the best set of operational parameters while miniaturizing the overall size. The necessary hardware and software will be developed to achieve high frequency real time operation (30 KHz). The design will be prototyped and evaluated to determine the operational limitations and capabilities. The main research emphasis will be on system development, with applications directed at noncontacting modal analysis of structures. Specifically the incorporation of the rotational degrees of freedom into the experimental modal data base will be examined using the new measurement capability presented by this system.