Detection of concealed holes with Thermal Imaging
The EVT Hole and Void Inspector (HVI)
The HVI can detect concealed holes and voides in diverse material such as e.g. wood, caoutchouc, plastic, foamed material or fiber-reinforced plastic material.
The HVI is based on active thermal imaging. This means the object is heated with a ray of e.g. a high power flash. Aftwards it is monitored how fast the material is cooling down. Due to the different head dissipation of the material and the concealed hole, the latter can be detected. This also works with exothermic production processes such as e.g. when foaming up plastic. Here it is not necessary to heat the material. It is sufficient to capture the plastic immediately after the production with a thermal imaging camera.
On the base of the captured image sequence the cooling down is inspected. The holes and the material cool down in a different speed, so the holes can be detected.
Many Interfaces for Integration into the plant
The embedding of the HVI in a plant is carried out via the available interfaces. These are firstly, two independent GigE camera interfaces, where up to four cameras can be connected and controlled. Therefore even very large objects can be captured. And secondly, another two interfaces, one for a field bus such as Profinet, Modbus, etc. and the other for the integration into a SCADA system. Therefore the plant can control the thermal evaluation process and also reject the products depending on the result. At the same time the inspection results with the thermal images can be sent to the quality management.
Display or Headless System
You can run the HVI with a display. Therefore an error can be seen directly on the display. Alternatively you can run the HVI as headless system. This means the system sends only the inspection results and by request the evaluation images to a master computer or via web server to a browser.
The evaluation possibilities of the HVI are manifold and can be adjusted tot he requirements of the task. The creation of an inspection process is carried out with the drag-and-drop function. The results can either be communicated to a PLC or via the 8 in- and 8 outputs in 24V technology, light signals can be controlled or the inspection process can be initialized.