Hardware-in-the-loop simulation: Difference between revisions

Revision as of 15:59, 4 October 2020

Latest revision as of 10:07, 10 August 2025

(25 intermediate revisions by 19 users not shown)

Line 1:

{{short description|Technique used in the development and testtesting of complex real-time embedded systems}}

'''Hardware-in-the-loop''' ('''HIL''') '''[[simulation]]''', oralso known by various acronyms such as '''HiL''', '''HITL''', and '''HWIL''', is a technique that is used in the development and testtesting of complex real-time [[embedded systems]]. HIL simulation provides an effective testing [[platform (computing)|platform]] by adding the complexity of the plantprocess-actuator undersystem, known as a [[Plant (control theory)|plant]], to the test platform. The complexity of the plant under control is included in testtesting and development by adding a [[Representation (mathematics)|mathematical representation]] of all related [[dynamic systems]]. These mathematical representations are referred to as the “plant"plant simulation”simulation". The embedded system to be tested interacts with this plant simulation.

==How HIL works==

A HIL simulation must include electrical emulation of sensors and actuators. These electrical emulations act as the interface between the plant simulation and the embedded system under test. The value of each electrically emulated sensor is controlled by the plant simulation and is read by the embedded system under test (feedback). Likewise, the embedded system under test implements its control [[algorithms]] by outputting actuator control signals. Changes in the control signals result in changes to variable values in the plant simulation.

For example, a HIL simulation platform for the development of [[Anti-lock brake|automotive anti-lock braking systems]] may have mathematical representations for each of the following subsystems in the plant simulation:<ref name=brake>T. Hwang, J. Rohl, K. Park, J. Hwang, K. H. Lee, K. Lee, S.-J. Lee, and Y.-J. Kim, "Development of HIL Systems for active Brake Control

Systems", ''SICE-ICASE International Joint Conference'', 2006.</ref>

* [[Vehicle dynamics]], such as suspension, wheels, tires, roll, pitch and yaw;

* Dynamics of the brake system’ssystem's hydraulic components;

* Road characteristics.

==Uses==

In many cases, the most effective way to develop an embedded system is to connect the embedded system to the real plant. In other cases, HIL simulation is more efficient. The metric of development and testtesting efficiency is typically a formula that includes the following factors:

1. Cost

2. Duration

Line 42:

===High-burden-rate plant===

In many cases, the plant is more expensive than a high fidelity, real-time simulator and therefore has a higher-burden rate. Therefore, it is more economical to develop and test while connected to a HIL simulator than the real plant. For jet engine manufacturers, HIL simulation is a fundamental part of engine development. The development of Full Authority Digital Engine Controllers (FADEC) for aircraft jet engines is an extreme example of a high-burden-rate plant. Each jet engine can cost millions of dollars. In contrast, a HIL simulator designed to test a jet engine manufacturer’smanufacturer's complete line of engines may demand merely a tenth of the cost of a single engine.

===Early process human factors development===

Line 61:

=== Automotive systems ===

In context of automotive applications "Hardware-in-the-loop simulation systems provide such a virtual vehicle for systems validation and verification."<ref name=powertrain>S.Raman, N. Sivashankar, W. Milam, W. Stuart, and S. Nabi, "Design and Implementation of HIL Simulators for Powertrain Control System Software Development", ''Proceedings of the American Control Conference'', 1999.</ref> Since in-vehicle driving tests for evaluating performance and diagnostic functionalities of [[Engine Control Unit|Engine Management Systems]] are often time-consuming, expensive and not reproducible, HIL simulators allow developers to validate new hardware and software automotive solutions, respecting quality requirements and [[time-to-market]] restrictions. In a typical HIL Simulator, a dedicated real-time processor executes mathematical models which emulate engine dynamics. In addition, an [[I/O]] unit allows the connection of vehicle [[sensors]] and [[actuators]] (which usually present high degree of non-linearity). Finally, the [[Electronic Control Unit]] (ECU) under test is connected to the system and stimulated by a set of vehicle maneuvers executed by the simulator. At this point, HIL simulation also offers a high degree of repeatability during testing phase.

In the literature, several HIL specific applications are reported and simplified HIL simulators were built according to some specific purpose.<ref name=brake/><ref>A. Cebi, L. Guvenc, M. Demirci, C. Karadeniz, K. Kanar, and E. Guraslan, "A low cost, portable engine electronic control unit hardware-in-the-loop test system", ''Proceedings of the IEEE International Symposium on Industrial Electronics'', 2005.</ref><ref>J. Du, Y. Wang, C. Yang, and H. Wang, "Hardware-in-the-loop simulation approach to testing controller of sequential turbocharging system", ''Proceedings of the IEEE International Conference on Automation and Logistics'', 2007.</ref> When testing a new ECU software release for example, experiments can be performed in open loop and therefore several engine dynamic models are no longer required. The strategy is restricted to the analysis of ECU outputs when excited by controlled inputs. In this case, a Micro HIL system (MHIL) offers a simpler and more economic solution.<ref name=palladino>A. Palladino, G. Fiengo, F. Giovagnini, and D. Lanzo, "A Micro Hardware-In-the-Loop Test System", ''IEEE European Control Conference'', 2009.</ref> Since complexity of models processing is dumped, a full-size HIL system is reduced into a portable device composed of a signal generator, an [[I/O]] board, and a console containing the actuators (external loads) to be connected to the ECU.

===Radar===

HIL simulation for [[radar]] systems have evolved from radar-jamming. [[Digital radio frequency memory|Digital Radio Frequency Memory]] (DRFM) systems are typically used to create false targets to confuse the radar in the battlefield, but these same systems can simulate a target in the laboratory. This configuration allows for the testing and evaluation of the radar system, reducing the need for flight trials (for airborne radar systems) and field tests (for search or tracking radars), and can give an early indication to the susceptibility of the radar to [[electronic warfare]] (EW) techniques.s

===Robotics===

Line 72:

===Power systems===

In recent years, HIL for power systems has been used for verifying the stability, operation, and fault tolerance of large-scale [[electrical grid]]s. Current-generation real-time processing platforms have the capability to model large-scale power systems in real-time. This includes systems with more than 10,000 buses with associated generators, loads, power-factor correction devices, and network interconnections.<ref>{{cite web|title=ePHASORsim Real-Time Transient Stability Simulator|url=http://www.opal-rt.com/sites/default/files/OPAL-RT_Presentation_ePHASORsim_RT13.pdf|accessdate=23 November 2013|archive-date=26 August 2014|archive-url=https://web.archive.org/web/20140826174821/http://www.opal-rt.com/sites/default/files/OPAL-RT_Presentation_ePHASORsim_RT13.pdf|url-status=dead}}</ref> These types of simulation platforms enable the evaluation and testing of large-scale power systems in a realistic emulated environment. Moreover, HIL for power systems has been used for investigating the integration of distributed resources, next-generation [[SCADA]] systems and [[Power Management Unit|power management units]], and [[STATCOM|static synchronous compensator]] devices.<ref>{{cite journalbook|last=Al-Hammouri|first=A.T|author2=Nordstrom, L. |author3=Chenine, M. |author4=Vanfretti, L. |author5=Honeth, N. |author6= Leelaruji, R. |title=2012 IEEE Power and Energy Society General Meeting |chapter=Virtualization of synchronized phasor measurement units within real-time simulators for smart grid applications |journalpublisher=Power and Energy Society General Meeting, 2012 IEEE|date=22 July 2012|pages=1–7|doi=10.1109/PESGM.2012.6344949|isbn=978-1-4673-2729-9|s2cid=10605905|chapter-url=http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-70274}}</ref>

===Offshore systems===

In offshore and marine engineering, control systems and mechanical structures are generally designed in parallel. Testing the control systems is only possible after integration. As a result, many errors are found that have to be solved during the commissioning, with the risks of personal injuries, damaging equipment and delays. To reduce these errors, HIL simulation is gaining widespread attention.<ref>{{cite conference |first1=T. A. |last1=Johansen |first2=T. I. |last2=Fossen |first3=B. |last3=Vik |title=Hardware-in-the-loop testing of DP systems |conference=DP Conference |___location=Houston |year = 2005}}</ref> This is reflected by the adoption of HIL simulation in the [[Det Norske Veritas]] rules.<ref>DNV. Rules for classification of Ships, Part 7 Ch 1 Sec 7 I. [[Enhanced System Verification]] - SiO, 2010</ref>

==References==