Process Solution



  • Compact footprint (W: 1522, D: 1263, H: 2100) mm³
  • Confocal laser scanning displacement sensor for contactless measurement
  • Total process cycle time: 1.2 min
  • Measurement range: ±0.3 mm
  • Resolution: 0.01 µm
  • Reference distance: 6 mm
  • Linearity deviation: ± 0.5% of F.S.
  • Real time process control
  • Intuitive HMI design
  • Automatic part handling system
  • Cleanroom class ISO 8 or higher

The IMSTec roughness measurement station is part of an overall concept for coating automation of orthopaedic implants. It represents a high end solution for a 100% automated and contactless part surface roughness determination. An integrated high precision laser scanning sensor mounted onto a linear motor axis for test section movements provides repeatable roughness measurements. For quality control the roughness measurement system is monitored on a regular basis performed with a single certified reference sample. The automated part handling process maximizes the mean time to assist.




IMSTec’s fully automated part surface roughness determination system targets measurement applications in particular for medical devices such as orthopaedic implants. The key component of the roughness measurement system is a high-precision confocal laser scanning displacement sensor. When the part-/fixture assembly is loaded into the measurement station it will be positioned for roughness measurement by a combination of seven actuators mounted on a solid granite table placed on four damping elements for enhanced stability and accuracy.

For test section movements the roughness measurement sensor is mounted onto a linear motor axis. The distance measurement for positioning the roughness laser scanner at working distance is provided by a Triangulation Sensor. Linear motor axis and sensors are able to rotate 90° provided by a rotary actuator which enables the system to measure parts at required test sections. For design and protection purposes the measurement system base module is enclosed with a construction made of bended and bolted sheet metal profiles covered with powder-coating. Depending on clean room class or request all covers can be provided in stainless steel.

Station sides and windows have unmovable transparent windows (polycarbonate or glass) allowing the view to the process area.  A filter fan unit (FFU) is installed on top of the station which provides a low turbulent uni-directional flow of clean air in the process area with an adjustable air velocity of 0.45 m/s ± 20%. The air velocity is controlled by a sensor located at the filter outlet as well as a differential pressure switch registering the differential pressure prevailing on the filter inside the process area. As part of a fully automated system part load/unload is accomplished by a robot. To ensure a save transfer and measurement application parts are screwed on a transfer fixture equipped with an RFID tag used for part traceability through the process.

In order to protect the roughness measurement sensor head from inadvertent tilting the sensor head is connected to a collision and overload protector. In the event of a collision the tool plate deflects while simultaneously actuating the systems emergency stop mechanism. The overload protector automatically returns to zero position when the collided part has been removed from the sensor housing.

For quality control the roughness measurements system is monitored on a regular basis performed with a reference test coupon which is mounted on a standard transfer fixture.
The roughness of the test sample is within specified operational range of the equipment. Process sequence, parts disposition and data management is executed by the LAS & PLC station software.