Multi-Axis Vibration Control

m+p VibControl provides coupled and uncoupled multi-axis vibration testing (MIMO) in a closed control loop. Test modes include random, sine, shock and time domain replication (road load simulation). Multi-axis motions are characteristic of field environments. The more a vibration test can replicate the field environment, the more realistically it can induce a vibration stress loading equivalent to that experienced by the product in the field.

Whereas a single-axis random or sine test can be defined by a single value at each frequency, a multi-axis test requires the definition of a complex matrix at each frequency representing all the demand levels, as well as the coherence and cross-phases between each pair. The flexible display arrangements allow tailoring to show just the required information for maximum clarity during test operation, while all measured data is recorded and available for later analysis. Where the cross-phases and coherences are defined, m+p VibControl will verify that the demanded control values are feasible and also within the capabilities of the system.

Applications of the m+p VibControl multi-axis controller include vehicle road load simulations for durability tests, testing of large and complicated structures for operational loading as well as earthquake simulation as per IEEE 344. Components and sub-assemblies are tested on specially designed shaker tables with motion in several degrees of freedom. For seismic qualification the test specimen is fixed to a multi-axis earth­quake shake table. Large structures such as complete automobiles, aircraft, rockets and railroad cars are excited on multiple shakers each directly attached to a load input point.

The m+p PCU4 phase and amplitude control unit ensures that up to four shakers are reliably synchronized and coupled together to act as one system. It processes sine, random and shock data in a frequency range from 5 Hz to ca. 3 kHz. This specialist phase and amplitude control unit is used for optimization of the effective shaker force in the special application case where shakers are rigidly coupled via a head expander or slip table.

Key Features

m+p VibControl for Multi-Axis Vibration Control (MIMO)

• MIMO test modes: random, sine, shock including SRS, time domain replication (road load simulation)
• Control using unique vibration profiles for each shaker
• Combine multiple vibration profiles and excite all frequencies at the same time using true random
• Reproduce measured time histories at each load input
• True multi-tasking without loss of real-time control increases test efficiencies
• Cross-coupling compensation of dynamic responses from multiple shakers
• Test sequencing for automated long-term durability testing
• Powerful m+p eReporter analysis tool for browsing, viewing, editing, analyzing and reporting data
• Easy-to-use GUI with familiar Microsoft Windows style
• Seamless import/export of test results into Microsoft Windows applications makes plenty of analysis options available
• Phase and amplitude control unit for up to four shakers