SM03 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Proceedings - PDF document

SM03 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Proceedings of the 1996 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA September 15-18, 1996 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Akihiro Kimura, Iwao zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA IEEE International Symposium on Computer-Aided Control System Design 3:lO Dearborn, MI Development of Engine Control System using Real Time Simulator M a e d a Engineering Div. I I Engine Component & System Development Center, Future Project Div. No. 1 Toyota Motor Corporation The control logic zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA 1 2 0 0 Mishuku Susono Shizuoka 410-1 1 Japan Abstract prototyping. For control logic developments, it is In automotive manufacturing, the use of precise necessary to know characteristics of the controlled objects. control is increasing to satisfy customers’ needs, such as can not be fixed until the hardware is fuel economy, air quality. To provide sufficient utility to completed However, all parts of the engine system may customers, engine control systems are becoming not be completedfor the development because it is difficult complicated. For this reason, engine control system to provide hardware prototypes timely. This situation will development requires long periods and many efforts. not be improved in near future, although a number of We applied two types of real time simulators to the efforts have been done. development of an engine control system. One is the It has been proposedthat incomplete parts couldbe replaced by r e a l time simulators. This method is called engine and vehicle simulator which receives the actuator signals, calculates engine operating conditions such as Hardware In the Loop Simulation W S ) . In this study, engine output toque, air fuel ratio, engine speed and two types of real time simulators have been developed. One vehicle behavior, such as vehicle speed, reaction force and is the engindvehicle simulator which we call “Virtual outputs sensor signals. The other is the control logic Engine and Vehicle”(Virtual Engine). And the other is the simulator substituting for apart of the engine control logic control logic simulator substituted for a part of the engine on production CPUs. control logic on the electronic control unit (ECU). We call of fuel injection control system was this the “Rapid Proto ECU” (WE). An application Many HILSs conhcted and the simulators have the potential to havebeenreportedin the last 10 years. gas emissions are greatly dependent on the zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA efficiently improve the development process of engine We also developedHILSs in the past but they have not been control systems. propagated among engine control system development engineers. The majorreason forthis is lackof flexibility. It 1. Introduction was difficult to adapt HILSs to new hardware systems In engine systems, the engine power and exhaust because the programs were written by FORTRAN or C language. To solve the problem above, we have adopted a c c u r a c y of engine control. To satisfy customers’ needs and to meet general purpose tools with graphical user interface (GUI) strict exhaust gas emission standards, engine control and C code generation to easily install required simulation systems have become so precise and complicated that long models and engine control logic on the real time periods and many engineers are necessary to ensure simulators. sufficient quality and reliability. In addition, the 0-7803-3032-3/96/$5.00 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA complexity of control systems makes it difficult to change 2. Virtual Engine and Vehicle Figure 1 shows the schematics of the Virtual the control logic because the side effects of revisions are difficult to identify through experimental and empirical Engine. The Virtual Engine is connected to the ECU to estimate closed loop characteristics. It receives the control methods. signals from the ECU Computer simulation technologies are strongly andretums the sensor output signals. expected to lead the rapid development and high quality The input/output signals of the Virtual Engine which are 0 1996 IEEE 157

also the corresponding outputlinput of the ECU zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA in Table zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA The modelis transformed to the C zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA the ECU have a resolution of zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA composed of the high zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA the pulse width of input signals, such as fuel injection zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA 0 to 20 volts. So, we dropped downthe voltage level by the listed a r e 1. The engine simulation model has been additional voltage divider in order to be accepted by the AD purposes in the engine control system development. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA developed using SIMULINK, a general purpose modeling converter. We used AD andDA converters with aresolution of 20 volts per 12 bits because AD converters installedon tool with GUI [l]. code 5 volt per 10 bits. To detect by Real-Time Workshop [2] and implemented on DSP-CIT speed calculation board and YO a n d idling speed control signals, the Virtual Engine must boards [3]. The Virtual Engine can be used for the following measure the time when a signal crosses the thresholdlevel. The requiredresolution is less than 4 micro seconds, which - simultaneous development of hardwardsoftware is the resolution of signal generation of the ECU. Weused the tasks. In addition, it zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA - evaluation of control algorithm a wave form capture board with 25 nano secondsresolution - debugging ECU hardwarelsoftware to meet our requirements. In engine controls, the Virtual - reappearance of problems in market Engine should simulate two crank angle sensor outputs. - calibration The former pulses at every 10 degrees of crank angle except conditions of outputs from the ECU, zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA The Virtual Engine makes it easy to analyze two for a teeth missing angle. The latter pulses once every complicated interference caused by many interrupts among revolution of crank. The required resolution of the output can reduce the high cost of pulse is less than 4 micro seconds which is the resolution following zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA experiments and repeat the same operating conditions, for of signal capture of the ECU. We used an additionalboard example cold start and warm up. Moreover, the Virtual to generate the pulse outputs which has 6 DSPs (Texas Engine can estimate the behavior under even unrealistic Instrument C3 1) attached to 6 DA converters, respectively. However , so that the ECU bugs the programs on C3 1 s check the crank angle and appear clearly. output the voltage only every 8 micro seconds. In another In developing Virtual Engine we considerd worh, we could not achieve the required resolution. We U 0 performance. Thevoltage level of battery is need pulse generators with higher resolution. Monitor Production ECU Virtual Engine and Vehicle Figure 1 Schematic of Virtual Engine and Vehicle Table 1 Input and output signals for Virtual Engine Acceleration pedal positi Shift lever position Engine crank angle 158