ABSTRACTHardware-in-the-loop (HIL) simulation is a real-time testingprocess that has been proven indispensable for the modernvehicle dynamics, powertrain, chassis and body systemselectronic controls development. The high quality standardsand robustness of the control algorithms can only be met bymeans of detailed vehicle plant simulation models. In the lastfew years, several efforts have been made to develop detailedplant models. Several tools for the vehicle modeling areavailable in the market and each tool has different anddistinct advantages. This paper addresses ways that dSPACEAutomotive Simulation Models (ASM) can support themodel-based development processes. Additional modernsoftware tools that were used in connection with the ASM areLMS AMESim and Mathworks SimDriveline (of Simscape).ASM is an open Matlab/Simulink model environment usedfor offline PC based simulation and online real-time platformHIL testing. The combinations of system models fromdifferent suppliers typically require significant adaptationeffort. dSPACE's ASM are ideally adapted to dSPACEhardware-in-the-loop simulators with real time capabilitywhereas the AMESim environment requires a specialprocedure to make it compliant with dSPACE real-timehardware. This paper describes how AMESim vehicledynamics, SimDriveline automatic transmission models andASM parallel hybrid vehicle models are integrated for adSPACE HIL real-time simulation environment.

INTRODUCTIONToday, depletion of petroleum resources with rising fuelprices have globally become a reason for concern, and it iscommonly thought throughout the world that currentautomotive technology will need to be adapted or replacedfor the future. To provide significant reductions in oil use andCO2 emissions there are a variety of different technologyoptions [1]. The most promising is fuel economyimprovement. Improving the fuel economy of vehicles has acrucial impact on the amount of oil imported. So far, the mostpromising technologies are hybrid electric vehicles (HEV).Hybrid vehicles, using current internal combustion engines(ICEs) as their primary power source, and batteries /electricmotors as energy buffer, have much higher fuel efficiencythan those powered by ICEs alone. A typical hybrid electricvehicle combines several complex components in itspowertrain such as combustion engines, electric motors,battery, automatic and/or power split transmission,intermediate clutches, etc. HEV contains complex interactionbetween different powertrain devices and incorporatescomplex electronic control unit (ECU) network. For thevehicles of the future, comprehensive ECU tests are morenecessary than ever before, as the complexity and extent ofthe software increases at a breathtaking speed [2]. The V-cycle is a widely recognized approach in the development ofelectronic control units (ECUs) which incorporates offlinecontroller development to HIL testing at the end ofdevelopment cycle. Development of ECU's and to test its

Hybrid Vehicle Model Development using ASM-AMESim-Simscape Co-Simulation for Real-TimeHIL Applications

2012-01-0932Published

04/16/2012

Kunal PatilTexas Tech. University

Sisay Kefyalew MolladSPACE

Tino SchulzedSPACE GmbH

Copyright © 2012 SAE International

doi:10.4271/2012-01-0932

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performance, one need to have real time models of all thepowertrain, driver, environmental condition such as road,traffic. In this context ready to use simulation environment isnecessary for controller development. dSPACE AutomotiveSimulation Models (ASM) which covers powertrain andvehicle dynamics area can support the model-baseddevelopment processes.

Automotive Simulation Models (ASM) are modeled inMATLAB/Simulink. Simulink's signal based modelingmethods are very flexible. The mathematical modeling usedin Simulink is its most important property. One advantagewith the signal flow modeling used in Simulink is that it canbe applied on many systems from different domains, as longas the equations describing the system behavior are knownand they can be expressed by state space equations. HoweverSimulink is difficult to use efficiently. It requires expertise inseveral areas like math, physics, and programming. Derivingsystem level equations is difficult and implementation of newmodels can be difficult to read and maintain. Moreover, it isnecessary to know which inputs are available and whichoutputs must be calculated in order to connect it with the restof the system. On the other hand, AMESim and SimDrivelineuses a physical modeling environment where pre-definedcomponents of different physical domains can beinterconnected using a drag and drop style to create acomplete system for modeling, simulation and analysis ofmechanical, electrical, hydraulic and pneumatic components.Model reflects the structure of the system. System levelequations are derived automatically. New technologies ordesigns can be easily incorporated into the model. With thephysical modeling software, simple and complex systems canbe modeled in one environment more easily than withSimulink's signal-based methods. Physical system modelingis simpler to work with, but is less flexible than the dSPACEASM modeling environment. Since ASM is developed withnative Simulink blocks it can be adapted to a wide variety ofpowertrain systems and offers maximum flexibility. Thepremise of the paper is that components from variousmodeling environments could be combined to produce thebest possible simulation for ECU testing. Paper shows anexample of such an integration of dSPACE ASM models,with AMESim vehicle dynamics and Transmission fromSimDriveline for parallel hybrid electric vehicle.

CONFIGURATION OF PARALLELHEVParallel hybrid design blends the torque of an electric motor/generator along the IC engine torque. In this drivetrain ICengine supplies its power mechanically to the wheels as in aconventional IC engine powered vehicle. It is assisted by anelectric motor that is mechanically coupled to the drive-line.Figure 1 shows the configuration of parallel HEV. In ECUnetwork, hybrid control unit (HCU) manages powertrain,electric and chassis ECU's such as engine ECU, transmission

ECU, motor control unit (MCU), battery management system(BMS). ECU's are connected by bus systems and each ECUinteracts with its plant by means of sensors and actuators.ASM models show several powertrain components.Combustion engine and electric motor coupled to drivetrainand drivetrain is connected to vehicle dynamics.

Figure 1. Configuration of Parallel HEV

Same structure needs to be reflected into simulation model. Inorder to develop hybrid control unit and test performance wehave to have models for individual powertrain, electric motor,battery, chassis, additional models like driver, environment aswell as complete ECU network.

AUTOMOTIVE SIMULATIONMODELS (ASM)Automotive Simulation Models (ASM) are modeled inMATLAB/Simulink for real time simulation of keyautomotive systems such as engines, vehicle dynamics, brakehydraulics, turbocharger, electrical system, exhaust system,traffic and trailer [3]. The implementation of each model isviewable right down to Simulink basic block level, so it iseasy to supplement or replace components with customer-specific models. ASMs are typically used on a dSPACEsimulator for hardware-in-the-loop testing of ECUs or duringthe design phase of controller algorithm for early validationby offline simulation. In ASM actual physical vehiclecharacteristics are represented by a multibody system with 24degrees of freedom. This consists of a drivetrain with elasticshafts, a table-based engine, two semi- empirical tire models,a nonlinear or table based vehicle multibody system withgeometrical suspension kinematics and aerodynamics, and asteering model. An environment with a road, maneuvers, and

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an open and closed-loop driver is included as well. Allparameters can be altered during run time.

Usability of the model strongly depends on parameterhandling. Parameterization is an important aspect in modelingof automotive systems. dSPACE ModelDesk is a tool forparameterizing ASM models. It also provides projecthandling and allows parameter sets to be downloaded tooffline and online simulations. MotionDesk has beendeveloped as a complement to the dSPACE tool chain tovisualize the movement of mechanical objects in the 3-Dworld.

dSPACE Simulator test runs can be visualized and automatedfrom PC. The ControlDesk software is used during testdevelopment to create layouts and test sequences that aretailor-made for the application.

ASM PARALLEL HYBRIDARCHITECTUREThe Figure 2 shows the top level of a parallel hybrid vehicleASM model. The MDL block contains the dynamic plantmodels - dSPACE ASM, Simdriveline & AMESimcomponents. The IO block contains the dSPACE real timeinterface (RTI) blocks which are interfaces between plantmodels and the dSPACE hardware. These blocks can be usedto build real time code, and to download and execute it ondSPACE hardware. In addition to the RTI blocks, the IOinterface subsystem consists of blocks for scaling signals,providing test automation access, and switching betweendifferent configurations. MDLUserInterface block definessingle point location from which the user can access thedynamic model. In this block signals can be converted intouser-specific units without disturbing the SI unit-orientedsignal flow in the real model. The parallel hybrid model isstructured in several main components.

Figure 3 shows the first layer of parallel hybrid model withseven components SoftECU, Gasoline Engine, Battery,Motor, Drivetrain, Vehicle dynamics and Environment. Theengine, motor, drivetrain, and the vehicle dynamic blocks areconnected via shaft speeds and shaft torques. The gasolineengine model can be used in combination with realcontrollers in a hardware-in-the-loop environment (onlinemode), or for simulation of a gasoline engine in combinationwith software controller algorithms (offline mode). The twoyellow blocks to the left and right of the model blocksmanage the signal mapping from and to the I/O. They alsomanage the signal flow to and from the soft ECU for offlinesimulation.

Figure 2. ASM Parallel Hybrid Model

ENGINEModel used for engine is gasoline engine basic model. Thismodel is a Simulink model used to simulate spark ignitioncombustion engine. The engine model simulates a fuelsystem, an engine combustion system, an air path, an enginecoolant system, and an exhaust system. The engine modelcontains components for an air path with a throttle and amanifold, and a piston engine which includes the air intakeand combustion simulation. The air path simulates the intakemanifold dynamics and the throttle. The air flow is controlledwith the throttle. A fully opened throttle allows the engine toreceive all of its required air mass flow, which results in themaximum engine torque. The intake manifold modelcalculates the manifold temperature, the manifold pressure,and the mass inside the manifold. The fuel system injects thefuel for the combustion into the manifold. The fuel systemcalculates the fuel mass flow by the measured injection time.Cooling system model calculates the cooling watertemperature from the actual torque and the friction torque.Engine combustion system describes the air flow through theinlet valve and the torque generation by the combustion. Forgasoline basic engine actual torque is calculated by a tablebased on the engine speed and the relative air mass flow.

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Figure 3. Parallel Hybrid Main Components

BATTERYThe battery model calculates the terminal voltage, the batterystate of charge (SOC) and the battery temperature as afunction of the charge and discharge current. The terminalvoltage model takes into account several battery effects suchas voltage of each battery cell according to SOC, innerresistance, inductance, diffusion behavior of battery. Theparameter values for the different resistances, the inductanceand capacitances are parameterized for one battery cell. Theheat generation and dissipation takes account of effects likeheat from the main reaction, loss reaction, ohmic losses andheat flux due to thermal radiation. The SOC is calculatedfrom battery current, temperature and loss current.

ELECTRIC MACHINEElectric machine is modeled as a permanent magnetsynchronous machine (PMSM). General modeling approachwhich is well known from industrial drive motor is used forHIL simulation purpose [4]. As the rotor has no electricalcircuit, only the stator windings are modeled. The PMSM ismodeled using dq notation in the synchronously rotatingreference frame. The real-time capability with respect tocalculation time and real time I/O is considered duringmodeling.

DRIVETRAINASM drivetrain model is a longitudinal model of a vehicledrivetrain with the components such as crankshaft,differential, starter and test bench. Drivetrain modelcalculates speed of the drivetrain, for example engine speed,motor speed, and gear train speed. The crankshaft modelcalculates the engine speed and motor speed by integration ofthe different drive torques such as clutch torque, meaneffective torque of the engine, and motor torque. Thedifferential model contains a simple ratio between the inputand output torque. Starter model initially speeds up theengine and generate external torque in order to accelerate thecrankshaft. When the engine reaches the startup speed, theelectronic control unit starts fuel injection and ignition.

The drivetrain model in this example incorporates torqueconverter, automatic transmission and a final drive modelfrom SimDriveline. SimDriveline software is based on theSimscape environment which is a physical modeling method[5]. Unlike other Simulink blocks, which representmathematical operations or operate on signals, Simscapeblocks represent physical components or relationshipsdirectly. Certain steps are involved in integratingSimDriveline drivetrain model with ASM model. Crankshaftand differential model of standard ASM drivetrain arereplaced by torque converter, automatic transmission and afinal drive models from the SimDriveline. Starter model andtest bench model are same as standard ASM drivetrain model.Most SimDriveline blocks have special driveline ports. Thesedriveline ports need to connect with driveline connectionlines which represent physical rotation axes. Torque istransfer along these driveline connection lines and inertiarotates around the line. Sensors and actuators blocks are usedto interface between SimDriveline blocks and normalSimulink blocks. Figure 4 describes torque actuator blockimposed externally defined engine torque on the engine shaft.

Figure 4. Simulink2Simdriveline Block

As shown in Figure 5, similar Simulink2Simdriveline blockis created for motor shaft. Actuator inputs and sensor outputsare Simulink signals that are used to interface with rest of theASM model components. As shown in figure rotational

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inertias are specified for different bodies such as engine,motor. Motion sensor blocks gives engine speed and motorspeed as an output.

Figure 6 shows converter with lockup clutch block whichincorporates torque converter from SimDriveline library.

Figure 6. Converter with Lock-up Clutch

Figure 7 shows seven-speed Lepelletier transmission modelfrom SimDriveline transmission templates, and how it isincorporated in the overall vehicle model. Transmissionmodel is based on planetary gear and ravigneaux gear.Properly engaging a transmission in a particular gear settingrequires engaging a certain number of clutches. Transmissioncontroller block consisting of Simulink Lookup and TransferFcn blocks, converts the single clutch control signal to a setof six clutch signals that shifts the seven speed transmissionthrough a fixed gear sequence. Single clutch control signalfor transmission controller comes from the ASM SoftECU fortransmission. ASM Soft ECU for transmission controls theseven speed Lepelletier transmission. It engages the gears andcontrols the lockup clutch according to lever position. In thedrive position, the SoftECU engages the first gear and shiftsautomatically according to the transmission output speed andthe accelerator pedal position. The lockup clutch is also

controlled according to vehicle speed and to the acceleratorpedal position. Driveline model is connected to SimDrivelineenvironment which defines solver for the system. One of therequirements is that the gear ratios should always be positive.If a gear ratio vanishes or becomes negative, theSimDriveline simulation stops with an error. In SimScapethere are some special ports that are connected with specialconnection lines. These connection lines are not normalSimulink lines. As a result, variables are not available inRTI's variable description file for these ports and connectionlines.

VEHICLE DYNAMICSIn this example AMESim vehicle dynamics model is used.LMS AMESim is simulation software for the modeling andanalysis of one-dimensional (1D) multi-domain systemsusing physical modeling environment [6]. As shown inFigure 8 vehicle dynamics model is created in AMESim.Figure shows AMESim to Simulink interface. The AMESimto Simulink interface enables you to construct a model of asubsystem in AMESim and to convert it to a Simulink S-Function.

As shown in Figure 9 the S-Function can then be importedand used into ASM model. The AMESim RT (Real-time)option enables the export of an AMESim model to a real-timeenvironment for use in hardware-in-the-loop (HIL)simulation.

AMESim environment requires a special procedure to make itcompliant with dSPACE real-time hardware. After the system(in this case longitudinal vehicle dynamics) has been modeledin AMESim, an interface s-function has to be created toreceive and/or send signals to Simulink model. The s-function is generated by switching to parameter mode andimport it to ASM/Simulink model while keeping theAMESim model open for Matlab to have access to the s-

Figure 5. Top Level Diagram of Drivetrain

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function and trace files which would otherwise be lost if theAMESim model is closed. Standard AMESim-Simulinkinterface uses Simulink solver so no need to worry about thesolver for real time interface. However, S-functionparameters of 1 and 0.01 have to be used to have AMESimresults printed with an interval of 0.01 sec. Since AMESimdoes not know the name of the ASM system that the codewill be used in, TRC file AMESIMMODELNAME_.trc isgenerated. To take this into account in dSPACE, the file mustbe renamed to ASMMODELNAME_usr.trc. The buildcommand also needs to have access to the name of theAMESim system in the circuit. This information is suppliedby the extra argument AMESIMMODEL=VehicleDynamicson the make command. Depending on the Matlab version andrealtime dSPACE software used, AMESim has a specificallydesign template make file (TMF located under $AME/lib) forbuilding the application.

The main advantage of the AMESim is to create highprecision models without writing a single line of code using

mathematical representation of the system behavior.However, its limitation lays with the difficulty of altering theequation of the system. Because the equation is built withinthe physical element, adding or removing functionality isdifficult and thus is less flexible than ASM models.

ENVIRONMENTThe environment subsystem is used to define drivingmaneuvers for the vehicle by means of stimulus maneuvers orat a specific vehicle speed controlled by the driver model.The road subsystem allows you to set environmentalconditions like road grade, friction coefficient, environmentalpressure, and temperature.

SOFT ECUThe soft ECU block contains models for Engine controller(ECM), transmission controller (TCU), hybrid controller(HCU). For the motor control unit real ECU has been used.ECM calculates injection time based on intended lambda

Figure 7. SimDriveline Transmission model incorporated in ASM

Figure 8. AMESim Vehicle Dynamics

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value, optimum ignition angle and throttle position. TCUcontrols the automatic gearbox. HCU soft ECU controlsengine on /off, torque request co-ordination, batterymanagement. Torque request co-ordination includes torquerequest for IC engine that has to be operated by soft ECUgasoline and torque request for electric motor that will beoperated by real ECU.

REAL TIME SIMULATION -SOLVERS USED AND LIMITATIONSFor the real time simulations fixed-step solver with balancingaccuracy and simulation speed must be used. For the currentsystem ASM plant model is using fixed step solver withODE1 method and time step of 1 millisecond. Electriccomponent models for ASM have to be solved with anappropriate solver. The equations are solved numerically bydiscrete methods, i.e. the Simulink solver has no effect on theequation solving technique. Three main solvers that wereutilized in the implementation are Forward-Euler, Backward-Euler and Tustin.

Efficient testing of ECUs for electric machines requires fastmeasurement and analysis of several closely associatedsignals. In this example, electric machine model runs at afaster rate than the rest of the model. Electric machine modelis computed at the carrier frequency of the PWM gate drivesignals from the ECU. The PWM signals coming from ECUare measured by the DS5202 PWM measurement solution,while calculated motor current signals are sent back tocontroller by means of analog voltage signals (DS2202DACs). Electric machine subsystem is driven by hardwareinterrupt block of DS5202. Since separate tasks can interrupteach other, the transfer of data vectors between them can alsobe interrupted, producing inconsistent data. Simulink's ratetransition blocks are used to handle the task transition.

SimDriveline models use the Simulink solver suite, so solversettings are same as the general Simulink models (ASM).Fixed step solver with larger tolerance and step size results inless simulation accuracy. It is always good to obtain referenceresults with variable step solver then find right balance

between accuracy and simulation speed using fixed stepsolver. Sample times of all SimDriveline blocks are alwayscontinuous so these blocks cannot be used with discretesolvers. For the fixed step solver clutch velocity tolerancevalue must be specified either in each clutch or in theconnected Driveline Environment block. In real timesimulation most SimDriveline parameters are not tunable;this is one of the limitations of SimDriveline. It is notpossible to generate a code from SimDriveline model thatcontains one or more S-functions generated from otherSimDriveline models.

Some AMESim systems are difficult or impossible to solveusing Simulink solver. In this case user can use co-simulation(in Simulink), or import the Simulink model into AMESimand use the AMESim solver for everything. In current systemmain purpose is to test and develop controller in ASMenvironment. For this purpose AMESim-Simulink interfaceuses Simulink fixed step solver. After the AMESim S-function is imported into Simulink, it is verified that theAMESim/Simulink system can run and give correct resultsusing a fixed step integration method with a time step of 1millisecond. By adding AMESim parameters to the AMESimwatch facility it is possible to change AMESim parameterswhile the simulation is running. The limitation is that manyAMESim parameters are not used directly in the calculation,but they are preprocessed in the initialization phase of thesimulation. The number of AMESim S-function blocksallowed in the Simulink model which is compiled with RTWis limited to one. It is possible to group the differentAMESim systems together in AMESim and import theAMESim system as one S-function.

CONFIGURATION OF A HILSIMULATOR FOR A PARALLEL HEVMODELFigure 10 shows interface level between ECU and HILsystem. For HIL simulation, motor control model istransferred to MicroAutoBox which will act as a real ECUand entire plant model is transferred to dSPACE simulator.

Figure 9. AMESim Vehicle Dynamics Model incorporated in ASM

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Electric motor needs more complex control system [7].Electric drive controller has different requirements regardingthe HIL simulator. Control loop of electric drive is not onlyclosed by motor speed but also by a current loop. Incombustion engine HIL simulators, only low power actuatorsare controlled electrically, while in electric drive entirecontrolled power is electrical. In order to test under realpower conditions, complete motor test bench has to beintegrated. However with signal level simulation, it ispossible to test real time motor controller without realinverter.

In signal level simulation real voltages and currents are notpresent physically, but only in simulation. This type of HILtesting is advantageous because of low cost, no safety issues.From hardware point of view there is no limitation aboutmachine parameters. We can test 2 kW or 40 kW electricmotor with the same test setup. Each physical effect can betaken into account Offline- and Online- Simulation with thesame model. Disadvatages of signal level simulation includesseperate power stages necessary and there is no test of realpower stages.

In this example simulation model is connected to standardI/Os of the motor controller, such as interfaces to motorposition sensor, communication interface CAN. Electricmotor in simulation model uses current control loopscomputed every PWM period from ECU. An accurate

measurement of three phase center pulse PWM control signalis performed by a hardware ds5202 board.

MODEL DESKFor parameterizing and managing the parameter sets ofparallel hybrid, dSPACE ModelDesk is used. Figure 11shows overview of ModelDesk. Arrows indicate thatModelDesk can be used for offline Simulink simulation ofASM model and online real time simulation on dSPACEhardware. Parameter files are created and assigned to eachmodel component, for example, differential, tires and road.Complete vehicle parameter sets are created and managed.ModelDesk has additional capabilities such as Roadgenerator which is GUI for defining road segments andcreating test tracks. Maneuver editor is used to create drivingmaneuvers such as follow road, increase acceleration, brake,driver aggressiveness, etc. Traffic editor can create trafficscenarios for displaying simulated traffic situations such asvehicles overtaking and changing lanes. The Plot Managercan be used to visualize signals of the simulation model andto manage the simulation results. The new blocks forAMESim vehicle dynamics and SimDriveline are stored incustom library. These custom libraries are integrated inModelDesk. The ModelDesk automation interface allows tochange parameter values, select roads, and specify maneuversusing scripts.

Figure 10. Electric Motor I/O Interface

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TURNAROUND TIMEThe turnaround time for a task is the time that passes betweenthe triggering and the end of its execution. For real timesimulation an overrun situation occurs if a task is requested tostart but has not finished its previous execution yet. To avoidoverrun situation, solvers and time step setting should be suchthat it provides accurate results while permitting real-timesimulation. Table 1, shows the turnaround time on HILsimulator for different model combinations. Based on thecomparison it is seen that there is 30 μs difference betweenASM model and combined model. However based oncomplexity of model components from different environmentturnaround time will vary. Parallel hybrid model is running inmultiple timer task modes. Figure 12 shows turnaround time

for HIL simulator, MicroAutoBox and PWM hardwareinterrupt which is 262 μs, 24 μs and 11 μs respectively.

CONTROLDESK USER INTERFACEThe entire graphical user interface is implemented withdSPACE ControlDesk. It provides all the functions to control,monitor and automate experiments and makes thedevelopment of controllers more effective. User can easilyinteract with system and manage the real-time experimentsusing ControlDesk GUI as shown in Figure 13 below.

Figure 14 shows motor controller input and output signals.The output of the ECU is low PWM pulses that will operatethe inverter. Three phase duty cycle as shown in figure is fedto DS5202 FPGA based PWM capture solution. The outputs

Figure 11. ModelDesk Overview

Table 1. Turnaround Time Comparison

of motor model are current and speed signals and fed back tothe ECU.

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Figure 12. Turnaround Time for Different Tasks

Figure 13. ControlDesk Graphical User Interface

Figure 14. Measured Duty Cycle and Three Phase Current on ECU

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From the controller point of view a HEV is a complexinteraction of powertrain components and controllerfunctions. For the development of such controller functionsdSPACE offers all necessary components: AutomotiveSimulation Models (ASM) for plant modeling and proper I/Ointerfaces and real-time systems. Real time simulation of asystem requires balance between complexity of model, solvertype, solver settings and real time hardware. ASM providesseveral capabilities that make it easier to use it for real-timesimulation. ASM can be used throughout the developmentprocess as controller development on PC and Hardware-in-the-loop (HIL) test of real controller. With the use of ASMready to use plant models, developer can focus more oncontrol systems development. ASM also allows integration ofmodels developed in different environment. AMESim andSimDriveline model has been integrated in ASM and testedon real time system. Solver settings and limitations for eachtool are described. In addition to this ModelDesk allowshandling of complex parameterset and managing ofsimulation run and simulation result.

REFERENCES1. Maples, Moore, Patterson and Schaper 2000. “AlternativeFuels for U.S. Transportation” Transportation ResearchBoard Business Office, Washington, DC2. dSPACE Magazine 1/2010, Mar 2010, ‘Virtual EnergyCells’ BMW Group, Germany3. dSPACE GmbH: dSPACE Automotive SimulationModels, Product Information. Paderborn, Germany, 2010.4. dSPACE GmbH: dSPACE ASM Electric components,Product Information, Paderborn, Germany, 2010.5. SimDriveline ‘Introducing the Transmission TemplatesLibrary’, Product Information. http://www.mathworks.com6. AMESim, Simulink Interface, AMEHelp, LMS ImagineLab AMESim_Rev10SL17. Wagener, A., Schulte, T., Waeltermann, P., and Schuette,H., “Hardware-in-the-Loop Test Systems for Electric Motorsin Advanced Powertrain Applications,” SAE Technical Paper2007-01-0498, 2007, doi:10.4271/2007-01-0498.

CONTACT INFORMATIONKunal PatilPhD StudentTexas Tech University, USAkunal.patil@ttu.edu

Tino SchulzeProduct Manager ASM / ModelDeskdSPACE GmbH, Germanytschulze@dspace.de

Sisay MollaApplication EngineerdSPACE Inc, USAsmolla@dspaceinc.com

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CONCLUSION

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