End-of-line or in-line quality control
End-of-line (EoL) testing is the process of checking the quality of the manufactured product at the end of the production line and assessing it as OK or not OK. In contrast to EoL testing, in-line testing involves testing and evaluating product quality directly during the manufacturing process. Depending on the product to be tested and the quality criteria, different sensors are used to ensure the quality of the delivered product.
Learn how laser-optical sensors and non-contact testing of the acoustic signature helps in end-of-line testing!
Vibro-acoustic end-of-line quality control
Accelerometers, microphones or Laser Doppler Vibrometers (LDV) are generally used when quality control is required for vibration, acoustics and/or structure-borne noise. Laser Doppler vibrometers have the advantage of being non-contact and therefore do not require a sensor feed as is the case with accelerometers. Also, unlike a microphone, LDVs cannot be influenced by ambient noise.
Advantages of EoL vibration testing
- Non-contact: Non-reactive, even in hard-to-reach areas
- Auto focus: Reliable measurement results at short and long distances
- Reliable: Unaffected by ambient noise
- High precision: Valid data detecting even small differences
- Easy integration: Interfaces for PLC and test systems
End-of-line vibration testing with laser vibrometers
In addition to the reliability of the test equipment, end-of-line testing also depends on easy integration into the test station and automation capability to achieve the highest possible test throughput. Laser Doppler vibrometers (LDV) offer advantages in all these areas.
Because vibrometer EoL testing works in a non-contact way with a flexible, adjustable working distance, LDVs can reliably measure at some distance from the test specimen. In addition, a signal can be recorded and analyzed at measurement points that are inaccessible to accelerometers. The high accuracy means that extremely precise data can be recorded and even the smallest changes in test results can be detected. Integration into the production system and communication with the PLC process control system is also possible.
Stand-off distance, frequency and min/max acceleration values?
Become an EoL testing expert: tips, tricks & video tutorials
The IVS-500 Industrial Vibration Sensor from Polytec is a dedicated and flexible measuring device for end-of-line testing on behalf of the vibro-acoustic signature or a produced part or assembly.
This exclusive section (login) provides an overview, the basics of acoustic testing using laser vibrometers and a practical benchmark and comparison to alternative EoL testing methods, as well as valuable tips & tricks in video tutorials for the use and handling of the IVS-500 Industrial Vibration Sensor - for starters, users, integrators and experts.
Related products
IVS-500 Industrial Vibration Sensor
The IVS-500 Industrial Vibration Sensor is key to fast and non-contact vibro-acoustic quality inspection, structure-borne noise analysis and reliable pass-fail decisions. Its robust and compact design enables a smooth integration into process control systems for in-line and production testing up to 100 kHz, whenever requiring short cycle times like for end-of-line tests. The sensor is wear-free and avoids expensive servo-mechanisms or noise protection cabins.
PSV QTec Scanning Vibrometer
PSV QTec Scanning Vibrometers take full-field vibration mapping to the next level with unrivalled optical sensitivity! Their innovative, patented QTec® technology uses multi-path interferometry based on infrared (SWIR) laser granting high-fidelity measurements on all surfaces from DC to 25 MHz. PSV QTec significantly reduce testing time - especially on dark, biological, rotating or moving objects, determining operational deflection shapes and Eigenmodes for NVH, acoustics, structural dynamics, ultrasonics, FEM validation and NDT.
Further applications
- Resonance testing
![Resonance testing and acoustic resonance analysis using optical vibration sensors (laser vibrometers)]( "Resonance testing and acoustic resonance analysis using optical vibration sensors (laser vibrometers)")
Resonance testing and acoustic resonance analysis using optical vibration sensors (laser vibrometers) - Amplitude measurement
![Measure vibration amplitudes optically: analyze structure-borne sound for amplitude measurement using laser measurement technology]( "Measure vibration amplitudes optically: analyze structure-borne sound for amplitude measurement using laser measurement technology")
Measure vibration amplitudes optically: analyze structure-borne sound for amplitude measurement using laser measurement technology - Actuators and drives
![Production testing of electric drives using in-line laser vibration measurement]( "Production testing of electric drives using in-line laser vibration measurement")
Production testing of electric drives using in-line laser vibration measurement - White goods
![Production testing on white goods, using laser vibration sensors for automated quality inspection]( "Production testing on white goods, using laser vibration sensors for automated quality inspection")
Production testing on white goods, using laser vibration sensors for automated quality inspection - Injection valves
![Production testing and quality control of fuel injectors with laser vibrometers]( "Production testing and quality control of fuel injectors with laser vibrometers")
Production testing and quality control of fuel injectors with laser vibrometers - Medical devices
![Production testing with industrial laser vibrometers on membranes in medical technology]( "Production testing with industrial laser vibrometers on membranes in medical technology")
Production testing with industrial laser vibrometers on membranes in medical technology - Engine cold test
![Non-contact vibration measurement as end-of-line production testing]( "Non-contact vibration measurement as end-of-line production testing")
Non-contact vibration measurement as end-of-line production testing
