Drivven Prototypes an FPGA-Based Engine Controller for a
Yamaha YZF-R6 Super-Sport Motorcycle
Drivven teamed up with National Instruments to prototype an engine control system for a 2004 Yamaha YZF-R6 super-sport motorcycle. National Instruments recently introduced a new product in their Reconfigurable I/O (RIO) hardware line called CompactRIO (cRIO). Drivven applied their FPGA-based and RT-based powertrain control VIs to the cRIO to replace the functionality of the factory ECU. Drivven also developed a trio of general purpose powertrain I/O modules, which plug into the cRIO, to interface with the factory sensors and actuators.
Mapping the Factory ECU
With the cRIO tucked away in the tail-section of the bike, and tapped into key sensor and actuator signals, Drivven was able to monitor and record these signals at 200 Hz to the cRIO flash file system. The signals included intake air pressure, barometric air pressure, intake air temperature, coolant temperature, throttle position, crank position, cam position, fuel injector solenoid and ignition coil. Drivven's FPGA-based engine management VIs were used to track the position of the crankshaft (0.3 degree resolution) and capture the angle-based timing of the fuel injector and spark events. The fuel injection pulse-width was also captured. This information was recorded while riding the bike at many different combinations of throttle position and engine speed (about 700 operating points) to fully map the behavior of the factory ECU. An engineer in a chase vehicle was able to wirelessly ftp the data files from the cRIO to a laptop and analyze it immediately for coverage of all operating points.
Analyzing the Data
Drivven created a LabVIEW application to present the recorded data in 3D surfaces and 2D slices. An engineer was then able to visualize and graphically modify the data and fill in missing data points.
Controlling the Engine
After post processing, the data was applied to Drivven's speed-density and alpha-n engine control strategies to successfully control the high performance engine very closely to the functionality of the factory ECU. Experienced riders could not note any significant differences between the two controllers. Once again, Drivven's configurable FPGA-based engine management cores were used for tracking the position of the crankshaft while generating precisely timed fuel and spark pulses in the angle/time domain. These FPGA-based engine management IP cores were one reason Drivven was able to complete the entire project with two engineers (in extracurricular time) in under three months. Since Drivven was able to successfully map the behavior of the factory ECU while riding the bike on the street, no dynamometer time was needed for mapping or tuning the control to achieve acceptable performance.
What was the purpose of this project? Since Drivven specializes in providing research and production powertrain control systems based on FPGA technology, this project was an exciting opportunity to demonstrate the automotive electronics expertise Drivven has to offer. The purpose of this project was not to achieve better engine performance over the factory ECU (although it would certainly be possible after some dyno time). The purpose was to demonstrate Drivven's ability to provide customers with an FPGA-based, turn-key powertrain research and development platform installed in their test cell or vehicle. These system give engineers full authority and access to control algorithms and calibrations as well as the ability to quickly add new features.
How Can Powertrain Control Engineers Benefit?
Drivven is taking advantage of flexible FPGA technology to design powertrain control systems for research and production applications. These systems can be quickly modified, and the underlying FPGA IP cores are directly portable to any FPGA-based platform. So, the same FPGA cores used on a research platform can also be used, without any modification, in a production controller, giving the same behavior and code interface on both platforms. Also, the same cores can be used across many different powertrain systems from the simplest to the most complex applications. For example, the same fuel injector core can be used on a simple single-cylinder application as well as a sophisticated eight-cylinder application. Engineers who have written and maintained many different low-level engine management software drivers to support multiple CPUs can realize the benefit of a single driver for all applications.
If you need to turn a super-sport motorcycle engine into an engine research platform, need a prototype racing controller, or need to develop your next-generation production powertrain controller based on flexible FPGA technology, contact Drivven today.
Check out this stand-alone video of the Drivven/NI bike under Drivven/cRIO control in Austin, Tx.