Laser Tracker Atmospheric Error Compensation Procedures
Compensate laser tracker atmospheric error using Edlen index calculations, distributed sensor arrays, and line-integral math to eliminate scale bias.
Acoustic Standing Waves
Meaning
Stationary pressure fields occur when incident and reflected sound waves interfere within an enclosed cavity. Acoustic standing waves are established when the distance between boundary surfaces matches an integer multiple of half the acoustic wavelength. These sustained patterns create localized regions of maximum pressure variation and regions of zero variation.
The phenomenon is restricted to geometries where the dimensions are comparable to or larger than the acoustic wavelength, making it highly dependent on the internal layout of a module.
Resonance Profile
Frequency alignment determines the pressure amplitude within the chamber. High acoustic pressure at the boundary walls can disturb optical alignment or mechanical sensors in smart devices. If the source frequency shifts, the pressure peaks shift position or disappear entirely.
This distribution of mechanical stress affects the reliability of thin-membrane sensors.
Cavity Effect
Enclosures can support multi-dimensional pressure nodes that alter local air density. Such localized density variations can affect precision measurements or the movement of delicate components. The distribution is calculated using the speed of sound and the physical dimensions of the enclosure.
Acoustic Boundary
Rigid walls act as reflection points that determine the locations of nodes and antinodes. Dense materials reflect almost all incident energy, while soft materials absorb it and suppress the standing pattern. Damping materials are placed at high-velocity points to minimize these acoustic standing waves in compact enclosures.