DJB is providing a training programme this year for engineers in the effective use of vibration accelerometers for data acquisition and analysis.
Advances in engineering analysis software have without doubt opened new doors for faster development and better access to results, however the question remains as to whether it has all been for the better.
Historically, data acquisition and analysis was a tricky business and engineers had to be on top of their game to ensure all the variables were correctly set to provide accurate data. As a result, engineers developed a deep understanding of their craft and from that came the ‘gut feeling’ if something was right or wrong. This ‘old school’ approach was passed on for a while at least, but has it now come to an end? Can we really determine good data from bad or is there a tendency to assume it is right because the software has been able to analyse it?
The issue with any modern acquisition system is that what goes in will be analysed regardless of its quality, so although it appears easy for a relative novice to get some frequency data or a structural analysis completed, the figures could be rubbish. This is not a criticism of the software of today, they are powerful tools, but it breeds complacency in engineers and as such, the risk of errors increases dramatically.
Any test system is made up of sensors, data acquisition and analysis software, but the point everyone seems to forget is that what comes out of one end is only as good as what goes into the other end, so in actual fact the sensor can be the most critical part of a system and there are many pitfalls to be avoided to ensure accurate and reliable data.
DJB Instruments UK focuses on vibration sensors, also known as accelerometers, for test and measurement applications and in this field of dynamic measurement the potential for errors caused by incorrect mounting, mass loading, poor calibration, incorrect cables, cross axis, noise etc. can cause errors of up to 35% in both amplitude and frequency deviation, a figure that any product development program would struggle to deal with.
The need for engineers to remain in control and continue to develop the ‘gut feeling’ to identify good and bad data remains as critical as ever. We are at a crossroads in the test engineering field and we need to look at all the options to find a way forward. A willingness to provide and attend training that draws on industry experience is key for both new and experienced engineers as there is always something new to learn.
DJB has been working for the last 5 years to offer something new in the dynamic testing field. Working independently, training has been offered both onsite as well as at their factory in Mildenhall, Suffolk. The aim is to educate engineers about the way data accuracy can be improved with a little more thought and focus on the accelerometer end of the test system. They have also teamed up with industry partners to present accelerometer training alongside signal processing basics.
Neill Ovenden, DJB’s Managing Director said ‘We make a point of keeping our training technically focused and stay away from a sales pitch. This has been presented widely in the UK and as far afield as the USA and India, the response has been excellent with 100% positive feedback. It gives both experienced and new engineers an opportunity to take a step back and address their testing processes for the better. The opportunity to see an accelerometer being built puts their use into perspective and engineers become more aware of their importance in the measurement system.’
In 2018, DJB is taking it a step further with courses already booked in the UK and plans to present to customers in the USA as well as a range of webinars later in the year to make the training global and on a bigger scale.
Training courses currently planned for 2018 involving DJB include:
* March 22nd 2018 – ‘Accelerometers the truth and more’ – Sensor City, Liverpool, UK
* April 25th 2018 – ‘Accelerometer Selection & Signal Processing Basics’ Riverside Hotel, Mildenhall. In association with Data Physics UK Ltd and Kemo Ltd.
* June 6th 2018 – ‘Accelerometers the truth and more’ – DJB HQ, Mildenhall, UK
* June 13th & 14th 2018 – ‘Vibration shaker testing’ – College Court, Leicester, UK (In association with Data Physics)