The combination of facilities at the LVV provides capability for dynamic testing of full-scale structures in ambient laboratory conditions and the opportunity to test substantial structures, sub-structures and components in realistic environments.
Here, staff from the University of Sheffield’s Laboratory for Verification & Validation (LVV) talk about partnering with Servotest for their unique Multi Axis Shake Table (MAST) system that is installed within an environmental chamber.
Dr Rob Barthorpe is the LVV Facility Manager & EPSRC Co-Investigator. Rob’s research covers the topics of structural health monitoring, model validation and uncertainty quantification. Rob was involved in the background, set-up and pre-sales discussions with Servotest.
Dr Robin Mills is the Technical Engineering Team Leader at the LVV and is responsible for the day to day running of the tests. Robin works with Servotest regularly to support incoming projects.
Mr Charlie Field is the LVV Business Development Manager. Charlie is responsible for business development at the LVV, ensuring the facility can successfully offer bespoke dynamic testing solutions to both the needs of academic research and industry projects. The Servotest MAST table is a unique selling point in that offering.
The LVV was part funded by the Engineering and Physical Sciences Research Council (EPSRC) and by the European Regional Development Fund (ERDF). It enables programmes of testing and research that will drive advances in V&V technology in the field of structural dynamics and beyond. It is larger and more versatile than any facility of its kind currently available for open academic and industrial use. The unique part of the research grant awarded to The University of Sheffield was the MAST within an environmental chamber. As such, the key part of this testimonial is about how we went about achieving that unique solution. There was an unusual start to the process, with the pre-sales initially conducted via the chamber supplier (Weiss Technik) with Servotest being introduced to the LVV team in 2014. It was the Servotest proposal for the unique MAST system that convinced Weiss that Servotest were the ideal partner for the LVV project.
During several meetings with the team at the LVV a bespoke test solution was developed. It started from a standard 2m x 2m Hexapod but soon evolved into a unique 3m x 2m MAST with custom capabilities including the capacity for a future upgrade to man-rated status.
We were principally looking for a solution that was going to work overall, giving us the required synergy between the MAST and the chamber. We had done a lot of background work to explore what different options might be available and what potential partners might be able to bring to the project. We were aware of other Servotest systems at the University of Sheffield so we had a good understanding of Servotest systems and a feel for what the company could offer to the LVV, particularly given the type of support that we would require.
Early on, Servotest worked with us to define what we could achieve, something that was made challenging given that the specification naturally evolved as the project developed. They helped us work out what was technically feasible in terms of a combined shaking and environmental facility, how it could best be packaged and how it could best be integrated with our new laboratory building. This gave us the confidence that there would be a workable solution at the end of the project. The initial specification evolved to comprise a larger 2m x 3m table with the added complication that all vertical loads were to be reacted vertically. This was required as a result of our particular system setup, with the MAST being installed on an air-sprung seismic mass. This in turn required Servotest to develop a unique design tailored to our application.
Those initial scoping and design discussions were the start of quite a long-term relationship to arrive at the table that’s operational in the LVV today. Between us we have dealt with the added complication of the project being funded via a research grant, meaning we had to work up a realistic solution as part of the original grant application and then had to deliver against that specification once the grant had been awarded, subject to the constraints of the grant itself. As a result the solution evolved to a fair extent over the course of the 12-18 months it took to get the grant awarded.
We soon realised we needed capability for man rating to cater for future tests and being able to include this as a future upgrade opportunity was helpful to the success of the grant application. Achieving man-rating will enable us to extend our audience and market in future. The relationship with Servotest enabled us to build in this important feature with the company very amenable to making it happen within our budget. Overall, this has enabled us to build a system that is completely bespoke and offers a unique set of capabilities for a University setting - something absolutely key to securing the funding for the project.
Trust in Servotest was originally built during the MAST design stage, but really came to the fore during the installation and commissioning phases. Initial trials revealed a number of bearings and sensors issues. These were dealt with in a straightforward manner, with Servotest immediately acknowledging the issues and being highly supportive in rectifying them quickly and professionally. Particularly worthy of note were Jags and Glen at Servotest for their dedication; they were knowledgeable, always available and very quick to pick things up. Having the flexibility of a multi-skilled team really helped in rapid resolution of these early problems. We always felt there was someone who would get back to us and had a genuine interest in getting things solved.
Another thing to mention is that during the commissioning stage the training was tailored specifically to suit our needs. This was something that was very valuable to us and enabled us to make a swift start once the handover was complete. Also valued was the fact that, following an unforeseen delay in the final handover of some of the equipment linked to the MAST, Glen was able come back and refresh us on our training. This surpassed our expectations and ensured that the value of the training was not lost due to issues that were out of either our or Servotest’s hands. Servotest were also present at our high profile launch event of which attendees included our funding bodies, members of Parliament and leaders of industry. Having Servotest on hand to ensure everything was running smoothly was very useful and much appreciated.
It’s a unique situation for a University research facility to have a MAST that can fully operate within an environmental chamber. The LVV team is small but offers a flexible service that benefits from extensive research experience and a wide network of contacts in both academia and industry. We do not just perform tests to a standard and issue certificates, almost every test we conduct is unique. To date we have worked with a wide range of academic research projects and industrial sectors, including aerospace, energy, robotics and civil seismic applications and activities. Companies come to us for both our testing capabilities and our expertise and following initial discussions we will often tailor a package to suit and achieve the required results to help customers make the decisions they need to make. It demonstrates the flexibility of what we do.
This flexibility is our main selling point and the ability to alter things during the testing process enables us to offer a tailored solution. Servotest have been very helpful in aiding us in implementing any changes in order for us to deliver on our key selling points. Customers and academic partners are finding that they can approach us with some fairly bespoke prototypes and desired test outcomes, and that we’re able to put together equally bespoke testing solutions. Our ability to do so is aided to a large extent by having Servotest on hand to back us up, aiding us in developing test solutions for these projects because of their detailed knowledge of our equipment and its capabilities.
We certainly feel we have a good working relationship with Servotest. This has been developed throughout the process from pre-sale, to installation and commissioning and on to post-sale support. We would hope that this partnership has enhanced Servotest’s reputation for seismic simulation equipment. We are regularly asked who supplied the MAST system when hosting visits at the LVV, and there is an appreciation from many of just what is involved in developing a system such as this and what Servotest have been able to provide. Those with an engineering or dynamics background are often keen to see the table from below to see just how things are put together and without exception walk away impressed. The performance of the table and its interaction with the test chamber differentiates our capability from anything else in the market and every project that we successfully deliver can only strengthen Servotest’s reputation as well.
We feel we’ve got a lot more than just a piece of equipment. Given the value of the MAST system and the energy we’ve put into the project as a whole, that level of support is critical. The partnership with Servotest has helped us establish a truly unique facility at the LVV and will help ensure its continued success.
For more information on LVV click the link https://www.lvv.ac.uk/explore-3d for a 3D walkthrough of the LVV facility.