Testing the Verification and Validation Capability of a DCP-Based Interface for Distributed Real-Time Applications

Cyber–physical systems (CPS) integrate diverse elements developed by various vendors, often dispersed geographically, posing significant development challenges. This paper presents an improved version of our previously developed co-simulation interface based on the non-proprietary Distributed Co-Simulation Protocol (DCP) standard, now optimized for broader hardware platform compatibility. The core contributions include a demonstration of the interface’s hardware-agnostic capabilities and its straightforward adaptability across different platforms. Furthermore, we provide a comparative analysis of our interface against the original DCP. It is validated via various X-in-the-Loop simulations, reinforcing the interface’s versatility and applicability in diverse scenarios, such as distributed real-time executions, verification and validation processes, or Intellectual Property protection.This research was funded by Basque Government through the ELKARTEK programme under the AUTOTRUS project (grant number KK-2023/00019) and the European Commission’s Horizon Europe programme under the METASAT project (grant 101082622)

METODO DI VALIDAZIONE DI TECNOLOGIE ROBOTICHE PER L’ISPEZIONE DI UN AMBIENTE NAVALE

Introduction The use of robotic technologies in ship inspections could lead to a significant reduction in costs, timing and problems related to the safety of the workplace. However, the application of autonomous systems in this field is still severely limited, both on a technological and regulatory level. It is necessary to demonstrate the effectiveness of these technologies in the field to support the human surveyor. Technical features There are currently no assessment methods available to verify the effectiveness of a ship inspection carried out using robotic technologies, checking that survey outcomes are at the same quality level of those commonly attainable by a human surveyor. Therefore, according to current regulations and traditional inspection techniques, validation methodologies based on the development of test equipment and protocols have been defined, aimed at verifying both the effectiveness of a robotic technology and of the involved personnel. As an innovative and pragmatic solution, it is proposed to experimentally test these technologies in a dedicated test environment, more economical and available than a ship, though able to simulate the reality on board in a controlled and repeatable way. Modular test equipment and protocols allow varying the parameters according to the needs and robotic technologies to be examined, by using different operating stations in which it is possible to simulate the actual conditions of a survey, detecting the degradation of the structure due to corrosion phenomena, fracture and mechanical damage. Possible Applications Shipbuilding engineering; Welded structures; Ship surveys and management; Applied robotic engineering and technologies; Training of inspection personnel. Advantages Simple and inexpensive method for verifying and validating the use of robotic technologies for ship inspections; Training centre for surveyors and pilots; Meeting place for the interaction and collaboration of different technology sectors, where to develop new knowledge and set rule requirements

A Generic Interface for x-in-the-Loop Simulations Based on Distributed Co-Simulation Protocol

Co-simulation is a key step in the development of today’s complex cyber-physical systems (CPS), specially in the integration and validation activities. However, performing a co-simulation involving models developed in different environments and possibly deployed in different platforms with mixed real-time and non real-time constraints is a challenging engineering task. A promising technology that could help overcome communication and synchronisation difficulties is the non-proprietary standard Distributed Co-simulation Protocol (DCP). This standard defines an application-level communication protocol, independent of the platform and the communication medium, that regulates the exchange of information between the co-simulation entities. This paper presents a co-simulation interface based on the DCP standard. It offers a novel approach to apply the DCP standard. Instead of using it as a model encapsulation mechanism, having to develop an specific DCP slave for each application, it is proposed to use it as a generic co-simulation interface. To this end, a Simulink library has been developed, allowing to connect models developed in Simulink with the outside world in an standardised way. Moreover, by exploiting the code generation potential of Simulink, a wide variety of devices become accessible, thus enabling x-in-the-loop simulations, which are commonly used tests in the verification and validation process of CPSs. This library has been tested in a soft real-time co-simulation application between a Simulink instance and an application running on a Xilinx Zynq Ultrascale+ System-on-Chip. As an additional contribution, an analysis of DCP synchronisation problems when simulating closed-loop systems composed of two slaves is performed. Finding that the main causes are the occurrence of random delays and that the simulations of the two slaves start at an arbitrary time. A possible solution to this problem is also presented

High-Speed piecewise affine virtual sensors

This paper proposes piecewise affine (PWA) virtual sensors for the estimation of unmeasured variables of nonlinear systems with unknown dynamics. The estimation functions are designed directly from measured inputs and outputs and have two important features. First, they enjoy convergence and optimality properties, based on classical results on parametric identification. Second, the PWA structure is based on a simplicial partition of the measurement space and allows one to implement very effectively the virtual sensor on a digital circuit. Due to the low cost of the required hardware for the implementation of such a particular structure and to the very high sampling frequencies that can be achieved, the approach is applicable to a wide range of industrial problems

Method for creating digital circuits of a feedback control system that implements an approximation technique for model predictive control (MPC)

In its most general aspect, the present invention relates to a method for creating digital circuits of a feedback control system that implements an approximation technique for Model Predictive Control (MPC). In addition to that, circuit architectures of the aforesaid control system are also described

Piecewise affine direct virtual sensors with Reduced Complexity

In this paper, a piecewise-affine direct virtual sensor is proposed for the estimation of unmeasured outputs of nonlinear systems whose dynamical model is unknown. In order to overcome the lack of a model, the virtual sensor is designed directly from measured inputs and outputs. The proposed approach generalizes a previous contribution, allowing one to design lower-complexity estimators. Indeed, the reduced-complexity approach strongly reduces the effect of the so-called "curse of dimensionality", and can be applied to relatively high-order systems, while enjoying all the convergence and optimality properties of the original approach

Synthesis of stabilizing model predictive controllers via canonical piecewise affine approximations

This paper proposes the use of canonical piecewise affine (PWA) functions for the approximation of linear MPC controllers over a regular simplicial partition of a given set of states of interest. Analysis tools based on the construction of PWA Lyapunov functions are provided for certifying the asymptotic stability of the resulting closed-loop system. The main advantage of the proposed controller synthesis approach is that the resulting stabilizing approximate MPC controller can be implemented on chip with sampling times in the order of tens of nanoseconds

Circuit Implementation of Piecewise-Affine Functions Based on a Binary Search Tree

In this paper we introduce a digital architecture implementing piecewise-affine functions defined over domains partitioned into polytopes: the functions are linear affine over each polytope. The polytope containing the input vector is found by exploring a previously constructed binary search tree. Once the polytope is detected, the function is evaluated by addressing an affine map whose coefficients are stored in a memory. The architecture has been implemented on FPGA and experimental results for a benchmark example are shown

Ultra-fast stabilizing model predictive control via canonical piecewise affine approximations

This paper investigates the use of canonical piecewise affine (PWA) functions for approximation and fast implementation of linear MPC controllers. The control law is approximated in an optimal way over a regular simplicial partition of a given set of states of interest. The stability properties of the resulting closed-loop system are analyzed by constructing a suitable PWA Lyapunov function. The main advantage of the proposed approach to the implementation of MPC controllers is that the resulting stabilizing approximate MPC controller can be implemented on chip with sampling times in the order of tens of nanoseconds

Integrated circuit implementation of multi-dimensional piecewise-linear functions

In this paper we present an integrated circuit implementing piecewise-linear (PWL) functions with three inputs, where each input can be either analog or digital. The PWL function to be implemented can be chosen by properly storing a set of coefficients in a 4 kB external memory. Experimental results are shown that demonstrate the circuit working up to 50 MHz with a maximum power consumption of 3.7 mW. Measurements corresponding to both static and time-varying inputs are provided and discussed. © 2010 Elsevier Inc. All rights reserved.Fil: Di Federico, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Poggi, Tomaso. Università degli Studi di Genova; ItaliaFil: Julian, Pedro Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages". Universidad Nacional del Sur. Departamento de Ingeniería Eléctrica y de Computadoras. Instituto de Investigaciones en Ingeniería Eléctrica "Alfredo Desages"; ArgentinaFil: Storace, Marco. Università degli Studi di Genova; Itali