Engineering Nonlinearity 4th Half-Yearly Meeting held 9-10 January 2017 at the University of Bristol

By Geraint Jones

The 4th Engineering Nonlinearity half-yearly Meeting took place at the University of Bristol on 9 and 10 January 2017. The Queen’s Building of the Faculty of Engineering at Bristol played host to around 40 attendees over two days from the project’s academic and industrial partners, also some Steering Committee members including Josie Robinson of the EPSRC, who took over as the project’s liaison near the end of 2016.

Queen’s Building New Wing Extension – Faculty of Engineering, University of Bristol
(Opening September 2017)

Proceedings opened on day 1 with a welcome and introduction from ENL Lead Prof. David Wagg, who then introduced the Keynote Lecture from Prof. Bruce Drinkwater, head of the Ultrasonics and Non-Destructive Testing group at the University of Bristol, which covered some fascinating aspects of ultrasonics including nonlinear effects, which were being exploited for levitation and positional manipulation of particles.

Prof Wagg then gave a review of ENL activities, recapping on the project’s three objectives:
– Modelling
– Identification
– Control
and its five scientific themes:
Theme 1 System identification
Theme 2 Random effects
Theme 3 Modal analysis and testing
Theme 4 Bifurcations and harsh nonlinearity
Theme 5 Active control

He then showcased nine areas with regards to Scientific Progress:
1. Identification and modal testing methods based on backbone curves
2. System identification using Approximate Bayesian Computation
3. Use of Weiner series for modelling randomly excited nonlinear system
4. Progress on hybrid models linking SEA and FEA
5. Further progress on constitutive laws for dynamic friction
6. Modelling of drillstring dynamics and rotor stator contact
7. Identification methods based on approximate Bayesian computation
8. Control based continuation
9. Nonlinear damping
and four events organised by or with a large presence from ENL
Airbus: Knowledge sharing workshop Feb 24 & 25 2016
RASD Southampton 4-6 July 2016
Annual Review Meeting at Southampton 6, 7 & 8 July 2016
EACS Conference Sheffield 11-13 July 2016

Prof Wagg gave special mention to the ten researchers who have gained academic positions, nine of them in the UK, having been involved with and in most cases directly funded by ENL. He then outlined that the purpose of the meeting was to network; to have a progress update; to share ideas; to consider what we can do better, and to plan the ENL showcase for July 2017 and what comes after ENL.
The rest of the formal proceedings for the day were taken up by the Theme Leaders and co-workers giving technical updates on the theme activities, in reverse order as is traditional at the half-yearly meetings, with Prof. Steve Elliott as session chair:
Theme 5 Active control – led by Steve Elliott
Theme 4 Bifurcations and harsh nonlinearity – led by Alan Champneys
Theme 3 Modal analysis and testing – led by Simon Neild and Jonathan Cooper
Theme 2 Random effects – led by Robin Langley
Theme 1 System identification – led by Keith Worden
Discussions formal and informal then continued into the evening at Pizza Express on Berkeley Square.

Day 2 was chaired by local host Prof. Simon Neild, who handed over first of all to Prof. Wagg to set the scene. Prof. Wagg outlined the agenda for the day, and then introduced the Industry Lecture:“Uncertainty Management Application to Design Load Setting And Robust Wing Twist MDA On A330 NEO, An AIRBUS Industrial Use Case” by Simon Coggon of Airbus.

Simon gave us a fascinating insight as to how uncertainly management can aid the industrial design process, in this case enabling Airbus to meet optimally a particular planned release of a new aircraft within a critical time slot.

A regular feature of ENL meetings is the elevator pitches given by the researchers and PhD students associated with ENL to promote their posters, and that followed next to whet the appetite for the subsequent poster session, which showcased in some more detail the excellent work being performed across the themes.
Josie Robinson then gave a very interesting and informative update on behalf of the EPSRC, outlining some upcoming political and funding influences on the research landscape, and signposting exciting initiatives such as the Global Challenged Research Fund (GCRF), the Industrial Strategy Challenge Fund, and progress and next steps for balancing capability (for Engineering).

Prof. Wagg then outlined the plans for the ENL showcase, to be held 3-5 July 2017 at the Diamond building University of Sheffield. This final showcase for the project would disseminate scientific results, accelerate impact from the project, celebrate the successes of ENL staff, and discuss and look to implement the legacy of the project.

Prof.Wagg then brought proceedings to a close by thanking everyone for attending, and providing a summary of the project’s strengths, and things for the project participants to emphasize in the final part of the project to early September 2017:

• Continuing high quality science being delivered
• People: continued success in developing academic careers
• Developing ideas at low to TRL levels (0 to 3): particularly basic & translational with some applied research

Things to emphasize in the final part of project:
• Applied research
• Exploitation and demonstration results for showcase
• PR: website, news & public engagement
• Interactions: both across network & other international researchers/groups use Linkedin network

EPSRC: Engineering and Physical Sciences Research Council