MIMO Random Vibration Control

Control Parameters

• Frequency Range: up to 4,900 Hz
• Spectral Resolution: 200, 400, 800, 1,600, 3,200 and 6,400. 3,200 for all 8 channels. 25,600 for 1 channel. Resolution higher than 1,600 may reduce the maximum channel count and the highest allowed overlap ratio.
• Loop Time: 12.5 ms for 2000 Hz. Loop time is the maximum time rate at which a controller executes complete cycles of sampling, processing data and transmitting control signals. It is the inverse of the socalled “real-time control bandwidth”.
• Average Number: 1 - 500 (2 - 1000 DOFs)
• Overlap Ratio: none, 50%, 75%, and 87.5%
• Control Dynamic Range: 90 dB
• Control Accuracy: ±1 dB at 99% confidence with 200 DOF
• Drive Sigma Clipping: 3 - 10, or disabled

Unique Advantages

Displacement Optimization for Random: A proprietary algorithm was developed to minimize displacement during Random Vibration Control testing. Displacement is reduced by 10% to 20% while the target PSD profile can still be reached. (Patent pending.)

Random Profile Import, Editing, and Reduction: Any saved power spectrum data, in various file formats, can be imported, modified, and used as the random profile. For compatible file formats, refer to the general EDM specifications. The imported spectrum may be modified by reducing the number of break points between two cursors and editing the profile table.

Safety Features:

• Abort Sensitivity: a single parameter allows the sensitivity and tolerance of various safety checks to be easily adjusted between customizable lower and upper bounds
• Shaker Safety Limits: limits for shaker acceleration, velocity, and displacement
• Open Loop Detection: open loop detection for the control signal and each input channel. Detection is based on maximum control loss or maximum RMS rate of change in the input channels.
• RMS Limits:: RMS limits for control signal
• Control Spectral Limits: spectral limits for control signal, starts at full level or low level
• Max Drive Limit: maximum voltage limit for drive output
• Shutdown: user-defined shutdown rate in dB per second

Vibration Utilities App

Crystal Instruments in partnership with our sister shaker company Sentek Dynamics provides users with the Vibration Utilities mobile app on iOS and Android. This app provides calculation features for sizing your vibration profile (Random, Sine or Shock) and searches through our catalogue of shakers and controllers for the best fit.

MIMO Random Vibration Testing Hardware

• Spider-80M - MIMO Vibration Testing System

MIMO Vibration Testing Software

• MIMO Shaker Systems
• MIMO Sine Vibration Testing
• MIMO Shock Vibration Testing
• MIMO TTH Vibration Testing
• MIMO Shock Response (SRS) Vibration Testing
• MIMO Time Wavveform Replication (TWR) Vibration Testing

Continuous Data Recording

During vibration control, all measurement input and drive signals can continuously record to a Spider-NAS or the internal storage residing in each front-end. Users can view and analyze data files with Crystal Instruments Post Analyzer. The variable sampling rate can be enabled to simultaneously record slow-change signals together with high speed vibration data.

Monitoring Through EDM Cloud

All vibration tests in EDM-VCS support status checks through EDM Cloud. With EDM Cloud support, users can set up any VCS test to upload live data or run logs for completed tests to a cloud storage space provided by Crystal Instruments, where data is securely stored in the user’s account.

The EDM Cloud website is located at https://cloud.go-ci.com. Users can access EDM Cloud from anywhere in the world to check the status of past and current tests. A secure login flow ensures the status can only be checked by authorized personnel with proper credentials. Multiple logins for accessing the same Cloud account is available.