Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Process monitoring: new bidirectional sensor » bd-1 « measures shape and roughness of shafts inline

28.04.2014

The Fraunhofer Institute for Laser Technology ILT has developed an interferometric distance sensor that can precisely measure the geometric features of shafts – for example, camshafts and crankshafts – with sub-micrometer accuracy. The compact » bd-1 « sensor head can be integrated into shaft measuring machines without any difficulty and also measures surface roughness as well as geometric features. Our experts will be demonstrating the sensor live at the Control 2014 trade fair in Stuttgart.

Crankshafts, driveshafts, and camshafts are found in all internal combustion engines. The automotive industry sets extremely high standards on the manufacturing accuracy and surface characteristics of these shafts.


The » bd-1 « sensor carrying out a shape and roughness measurement on a camshaft.

Source: Fraunhofer ILT, Aachen, Germany

For example, camshafts must work with microsecond precision in controlling valve opening times synchronous to piston movement. Even the tiniest manufacturing errors can greatly impair engine performance, fuel consumption, and the service life of components.

Deviations from the specified roundness or roughness values, for instance, can lead to increased wear, unwanted noises, and malfunctions. Not surprisingly, then, the 100% inspection of shafts on the assembly line calls for measurement technology that is ten times more accurate than values applying to manufacturing technology. Measuring deviations in shape and position requires measurement accuracy in the micrometer range, sometimes even in the range of a few hundred nanometers.

For the most part, shaft measuring machines still use tactile distance sensors and laser triangulation sensors that measure a variety of characteristics such as cam shape, cam lift, base circle radius, roundness, eccentricity, angular position, and straightness of bearing positions. Surface roughness is usually measured separately using perthometers.

» bd-1 « pushes back the limits of measurement technology

Now experts at Fraunhofer ILT have developed the bidirectional optical sensor » bd-1 «, which can measure both the shape and roughness of shafts inline and needs only a fraction of the installation space that triangulation sensors take up. Its name alludes to the fact that the laser beam moves back and forth along a »bidirectional« single path. This does away with adjustment problems, as the transmitter and receiver no longer have to be aligned with each other. In direct comparison with conventional triangulation sensors, » bd-1 « boasts a much lower linearity error value, putting it way ahead of the field.

» bd-1 « can measure all kinds of surfaces – including finely polished, shining, and reflective surfaces, which can be difficult to measure with other optical sensors. It not only measures surfaces positioned at steep angles and drill holes with high aspect ratios; it also records surface roughness while measuring deviations in shape on rotating shafts – eliminating the need for a separate process step and equipment specifically for this purpose.

Precise, rapid inline measurement for quality inspection and process monitoring

» bd-1 « recognizes deviations in shape and the microscopic surface structure of shafts at speeds of several thousand revolutions per minute with an accuracy in the 100-nm range. This is made possible by high-speed data acquisition and processing and distance measurement frequencies of up to 70 kHz in some cases. » bd-1 « thus achieves the precision of interferometric sensors and is faster than conventional absolute-measurement distance sensors. » bd-1 « can be used both for quality inspection on the assembly line and for process monitoring during manufacture.

The sensor also works reliably in rough environments. The window for the beam outlet and inlet has a diameter of < 5 mm and can therefore be effectively protected against dirt by means of an air current.

Flexible applications

Fraunhofer ILT developers created the distance sensor primarily for manufacturers of shafts or of high-precision cylinder coordinate measuring machines (CCMMs) for components such as camshafts and crankshafts. » bd-1 « is ideally suited to the 100-percent inline inspection of geometric features in accordance with the requirements of the automotive industry. In field tests, » bd-1 « has already proved how effectively it can measure the thickness of rolled strips and blown films inline, or carry out roundness and distance measurements during the manufacture of turned parts in machine tools.

Visitors to the Control international trade fair for quality assurance in Stuttgart, which is taking place from May 6 to 9, 2014, will have the opportunity to see » bd-1 « in action as it performs live measurements at the joint Fraunhofer booth 1/1502.

Contact

Dipl.-Phys. Christian Tulea
Clinical Dioagnostics and Microsurgical Systems Group
Phone +49 241 8906-431
christian.tulea@ilt.fraunhofer.de

PD Dr. Reinhard Noll
Head of the Competence Area Measurement Technology and EUV Sources
Phone +49 241 8906-138
reinhard.noll@ilt.fraunhofer.de

Fraunhofer Institute for Laser Technology ILT
Steinbachstraße 15
52074 Aachen, Germany
 

Weitere Informationen:

http://www.ilt.fraunhofer.de

Petra Nolis | Fraunhofer-Institut

More articles from Trade Fair News:

nachricht Fraunhofer IBMT presents Ultrasound Technology and Mobile Lab Technologies at IAA 2015
26.08.2015 | Fraunhofer-Institut für Biomedizinische Technik IBMT

nachricht The Expo Presents: Wellness for Dairy Cows
11.08.2015 | Rheinische Friedrich-Wilhelms-Universität Bonn

All articles from Trade Fair News >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: What would a tsunami in the Mediterranean look like?

A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).

Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...

Im Focus: Self-healing landscape: landslides after earthquake

In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.

These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...

Im Focus: FIC Proteins Send Bacteria Into Hibernation

Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.

For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...

Im Focus: Fraunhofer IPA develops prototype of intelligent care cart

It comes when called, bringing care utensils with it and recording how they are used: Fraunhofer IPA is developing an intelligent care cart that provides care staff with physical and informational support in their day-to-day work. The scientists at Fraunhofer IPA have now completed a first prototype. In doing so, they are continuing in their efforts to improve working conditions in the care sector and are developing solutions designed to address the challenges of demographic change.

Technical assistance systems can improve the difficult working conditions in residential nursing homes and hospitals by helping the staff in their work and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking conference in Heidelberg for outstanding mathematicians and computer scientists

20.08.2015 | Event News

Scientists meet in Münster for the world’s largest Chitin und Chitosan Conference

20.08.2015 | Event News

Large agribusiness management strategies

19.08.2015 | Event News

 
Latest News

Interstellar seeds could create oases of life

28.08.2015 | Physics and Astronomy

An ounce of prevention: Research advances on 'scourge' of transplant wards

28.08.2015 | Health and Medicine

Fish Oil-Diet Benefits May be Mediated by Gut Microbes

28.08.2015 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>