Using Laguerre functions to improve the tuning and performance of predictive functional control

This paper proposes a novel modification to the predictive functional control (PFC) algorithm to facilitate significant improvements in the tuning efficacy. The core concept is the use of an alternative parameterisation of the degrees of freedom in the PFC law. Building on recent insights into the potential of Laguerre functions in traditional MPC (Rossiter et al., 2010; Wang, 2009), the paper develops an appropriate framework for PFC and then demonstrates that these functions can be exploited to allow easier and more effective tuning in PFC as well as facilitating strong constraint handling properties. The proposed design approach and the associated tuning methodology are developed and their efficacy is demonstrated with a number of numerical examples

Input shaping for PFC: how and why?

Predictive functional control (PFC) is a highly successful strategy within industry, but for cases with challenging dynamics the most effective tuning approaches are still an active research area. This paper shows how one can deploy some insights from the more traditional model predictive control literature in order to enable systematic tuning and in particular, to ensure that the key PFC tuning parameter, that is the desired closed-loop time constant, is effective. In addition to enabling easier and more effective tuning, the proposed approach has the advantage of being simple to code and thus retaining the simplicity of implementation and tuning that is a key selling point of PFC. This paper focuses on design for open-loop unstable and also processes with significant under-damping in their open-loop behaviour

Shifting strategy for efficient block-based nonlinear model predictive control using real-time iterations

Nonlinear Model Predictive Control (NMPC) requires the use of efficient solutions and strategies for its implementation in fast/real-time systems. A popular approach for this is the Real Time Iteration (RTI) Scheme which uses a shifting strategy, namely the Initial Value Embedding (IVE), that shifts the solution from one sampling time to the next. However, this strategy together with other efficient strategies such as Move Blocking, present a recursive feasibility problem. This paper proposes a novel modified shifting strategy which preserve both recursive feasibility and stability properties, as well as achieves a significant reduction in the computational burden associated with the optimisation. The proposed approach is validated through a simulation of an inverted pendulum where it clearly outperforms other standard solutions in terms of performance and recursive feasibility properties. Additionally, the approach was tested on two computing platforms: a laptop with an i7 processor and a Beaglebone Blue Linux-based computer for robotic systems, where computational gains compared to existing approaches are shown to be as high as 100 times faster

Refreshing the D2N2 Strategic Economic Plan: the case for inclusive growth

The D2N2 Local Enterprise Partnership is in the process of revising its Strategic Economic Plan, which will run to 2030. The most recent D2N2 state of the economy report highlighted the persistent productivity gap and the inclusive growth challenge for the D2N2 area. Two detailed pieces of research have been commissioned on the challenges of productivity, and on inclusive growth in order to provide an evidence base to support the revision of the SEP. This report forms one of those pieces of research and as such will act as an integral piece of work to the SEP. With significant funding streams soon to expire, this SEP refresh has the opportunity to make its own case for a local economic strategy. The starting point for this report is that unless inclusive growth is the guiding principle of an economic strategy, rather than a strand of work, it is doomed to fail. Inclusive growth is an approach which has the potential to be transformative precisely because different policy and programme concerns are explored in terms of their impact across both the economic and the social. This is about what is done, but also about how it is done

Nottingham Express Transit: the role of green innovation in the drive for sustainable mobility through improved public transport

Traffic congestion at peak times has long been a problem facing cities in the UK. Latterly concern about combating congestion has been hightened by concerns over carbon emissions and poor air quality. In tackling these problems green innovations incorporating new technologies appear to have much to offer, although progress in implementing these sorts of innovation appears to have been slow. This case study on the efforts of one city to tackle these problems by pioneering a number of green innovations including the introduction of a light rail system employing trams known as Nottingham Express Transit (NET) as well as electric and gas-powered buses. The nature of these innovations is explored together with a detailed examination of how they came to be implemented and the impact they have had