In modern packaging and logistics processes, products are transported in a wide variety of materials: transparent films, glossy plastic packaging, black cardboard packaging or textured surfaces such as bubble wrap. This poses a central challenge for automation: objects must be reliably detected – regardless of their color, transparency or surface finish.
This is where tactile sensors in particular quickly reach their physical limits. But there is a technology that overcomes these hurdles: ultrasonic sensors. A current application shows why.
In conveying, packaging and handling processes, products and packaging change frequently – sometimes even within the same production batch. Nevertheless, a sensor should report reliably: Object present or not present?
Typical problem cases are
Optical sensors work with light. However, depending on the material, light is absorbed, reflected or transmitted. This leads to fluctuating signal strengths and, in the worst case, to incorrect switching or non-detection.
Ultrasonic sensors do not work with light, but with sound waves. These are emitted, reflected by the object and received again by the sensor. The decisive factor here is:
Optical properties such as color, transparency or gloss have no influence on the measurement.
Whether the packaging is clear, black, glossy or matt – it makes no difference to the ultrasonic sensors. As long as the object reflects sound (i.e. does not have a highly sound-absorbing surface), detection is stable.
This makes ultrasound particularly suitable for:
A decisive point in the integration of ultrasonic sensors is the installation situation. For a stable signal, the sensor should be aligned at a 90° angle to the object surface if possible.
If the angle is too shallow, the emitted sound can be deflected and no longer hits the receiving surface of the sensor. This is not a disadvantage of the technology, but a physical effect that should be taken into account in the design.
The U1KT series from wenglor, such as the U1KT001, is particularly suitable for such applications. This sensor combines several properties that are in demand in modern machine concepts:
Compactformat
The miniature design allows use even in very tight mounting spaces. This creates freedom in the design and is ideal for OEM machines or retrofits.
Large usable working range (30-400 mm)
The wide working range offers flexibility for different object distances – both for new installations and for retrofit projects in existing lines.
Material-independent detection
As ultrasound is not dependent on optical reflection, measurement results remain stable – even with transparent films, dark packaging or changing materials.
The combination of compactness, range and material independence makes ultrasonic sensors the ideal solution in areas such as:
Wherever products, packaging or materials change frequently, ultrasound ensures constant process reliability, whereas optical systems often have to be readjusted.
If objects are to be reliably detected despite changing colors, transparencies and surfaces, light-based sensor principles quickly reach their physical limits. Ultrasonic sensors circumvent this problem by design.
The U1KT001 is an example of how even demanding packaging and logistics applications can be reliably solved with a compact format, flexible working range and material-independent detection. Especially with varying materials, ultrasound is therefore not only an alternative, but often the more robust choice.
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