MajX-NVH Shield is a powerful NVH metric calculator. Signals can be processed in the time or angle domain leading to spectra, orders, time or angle based waveforms, transient indicators and sound quality measures. Metrics are pulled from these features and processed through pass/fail decision logic. Use NVH Shield to design signal processing, feature extraction and metric definition instructions for automated production pass/fail logic as implemented in MajX-NVH Controller.

Primary Features of MajX NVH Shield

• Define processing leading to metrics that can be used to define Pass/Fail logic

• Pass configuration definition to the MajX NVH controller

• Receive files from the MajX NVH Controller and process in parallel to metrics

• Typically implemented on a "roving" laptop or supervisory desktop overseeing one or more NVH Controllers via ethernet connection

• Multi-step test definition (1 test per product) with asynchronous processing for maximum speed

• Resampling to the rev domain against any number of tachometer signals

• Event marking through trigger logic and external events capture

• Spectrum computations and Order extractions in the time or angle domain

• Time or angle domain ensemble processing for transient detection and periodic events definition.

• Immediate process review by semi-live monitoring of the NVH controller

• Browser function to explore and retrieve previous tests from NVH controller or permanent database archive

• Data reporting utility for graphical feature overlays and audio playback of recorded signals.

MajX NVH Controller

The MajX NVH Controller implements metric computations defined in MajX NVH Shield. Autonomous measurements are initiated at the direction of your machines sequencing system. Metrics, Pass/Fail decisions and associated waveform are returned. The controller is typically implemented on a  National  Instruments PXI chassis accompanied by a variety of measurement hardware. The embedded PC runs a LabVIEW Real-time Operating system for maximum speed and reliability. Ethernet, serial, or other standardized communication protocols such as DeviceNET are used to communicate with the NVH controller.

Primary functions of the MajX NVH Controller

• React to test sequencing commands from a PLC, or other machine sequencing system

• Acquire data from a variety of dynamic sensors and compute metrics

• Send metrics back to the PLC or other plant data system.

• Interface with the MajX database Manager for autonomous long term archival of test data

• Interface with MajX-NVH Shield to permit optional live monitoring of ongoing tests and in-depth data review

• Manage sensor calibration procedures

MajX-Database Manager

The MajX Database Manager is used to scan one or more NVH controllers and move the raw datafiles and processed metrics to a server for archival and logging into an SQL compatible database. In a typical application, one or more NVH controllers are running autonomously in a plant or laboratory setting generating thousands, or even tens of  thousands of files monthly. Our Database manager communicates with our NVH controllers and executes the download of data independently of ongoing test operations.

Features of the MajX-Database Manager

• Autonomous archival of 10's of thousands of files monthly (typical)

• Searchable database of previously computed metrics

• Automatic file retrieval into MajX NVH Shield for review

MajX-DSA

MajX-DSA is a full-featured Dynamic Signal Analyzer offering spectrum analysis,  frequency response function testing, rotating machinery analysis, and torsional vibration analysis. Optional functions for dynamic multiplane balancing, formalized reporting templates and high channel count datalogging are available. MajX-DSA data files are compatible with MajX NVH Shield providing a comprehensive suite of NVH metric development tools. Use DSA for for field data acquisition, mapping studies, and benchmarking. Then move the data into Shield and prototype NVH metrics and evaluate robustness and repeatability for high volume automation.

Key features of MajX-DSA include:

• Spectrum analysis including two-channel functions (coherence, Frequency response, CrossPower)

• Impact testing for frequency response function estimation

• Adaptive re-sampling to arbitrary number of speed reference signals

• Digital counter support for high pulse encoders used to derive shaft speed and torsional vibration velocity signals.

• Adaptive re-sampling to angle domain against any available shaft speed reference.

• Multi-plane balancing utility

• Support for multi-rate acquisition for slow (temp, press, etc.) and fast (accelerometer , microphone, etc) data

• File review agility with unique playback slider