The new PMD laser line-scan profilers from ifm electronic offer a convenient, cost-effective and easy-to-use solution to the challenge of inline inspection of components and assemblies to detect manufacturing faults. Much more reliable than manual inspection – yet capable of detecting even small and subtle faults – PMD profilers are a fraction of the price of conventional vision systems and can be configured in minutes using just three integrated pushbuttons – no software is required.
The profilers work by scanning a line across a good sample of the object to be inspected and, using laser time-of-flight technology, storing a profile for this line. Subsequent objects are scanned in the same way and the results are compared with the stored version. If the deviation is greater than a user-definable limit, the profiler’s good/bad output changes state. The evaluation of the profile covers a specific ‘region of interest’ which again is user definable.
Key benefits of this method of operation are that results are unaffected by ambient light levels or by changing distance, over a wide range, between the profiler and the object being inspected. In addition, small faults, such as incorrectly tightening fixings, missing seals and defective or missing machining steps, can easily be detected. The profilers are also invaluable aids for applications such as product sorting and orientation.
Currently, ifm’s PMD profilers are offered in two versions. The OPD100 version allows users to set one region of interest and stores a single profile, while the OPD101 supports two regions of interest and stores up to ten profiles. Both versions offer standard switching outputs together with an IO-Link interface. The use of IO-Link in conjunction with the optional ifm Vision Assistant software package provides additional options, including the capture and display of scanned profiles.