Motorsport has always been a proving ground for new automotive technology and the uptake of CAN interfaces for diagnostic purposes is no exception. Much information can be gleaned from a vehicle’s CAN bus, so where once OBD-II tools reigned, CAN dataloggers are now being requested in aftermarket automotive situations, including motorsport.
“Data from different ECU’s can be read from the CAN-Bus with ease. Whilst ODB-II tools collect many values of interest, the data from an OBD-connector mostly comes from the central ECU and that data is not necessarily updated in real time and is limited,” commented Ansgar Gosling, general manager of agostec GmbH & Co. KG (Melle, Germany), when asked about CAN versus OBD-II. In contrast, if you connect the CAN datalogger directly to the CAN bus, you’ll collect that data in real-time and there will be no missing data.
An example of the adoption of CAN tools in motorsport is agostec’s work with Racing Team Bernd Kleeschulte. The team, which races in the 24 Hours Nurburgring GT and touring car endurance racing event as well as the European VLN Series, runs a BMW 320 on rapeseed oil produced by Kleeschulte’s company.
The use of rapeseed oil over diesel poses certain mechanical and electronic challenges. The BMW 320 is fuelled with 100% rapeseed oil, unlike other so-called ‘green’ racecars that invariably use a two-tank system, whereby the vehicle is started up on diesel and then switched to rapeseed once the engine is warm. MTO Engineering, a motorsport consultancy that works closely with agostec, looks after the ECUs, adjusting injection timing to suit the requirements of the fuel.
On this racing BMW, the team has removed the OEM ECUs that control peripheral road car style functions, as these are of no use on a racing car. This leaves a single central ECU to run the engine. However, some signals for these redundant peripherals are still required to enable the team to extract full power from the engine, so the team has employed CAN-bus simulation as a solution.
Agostec opted for Kvaser’s interfaces to connect a laptop running agostec’s Xtm CAN bus analysis software directly to the CAN bus. Generally the software allows the user to visualise and log all CAN data, collecting the data using the CAN Calibration Protocol (CCP) with a21 description files. The user then creates scripts to simulate the car’s wider network traffic with the goal of maximizing performance. After successfully testing the scripts whilst the car was running on MTO Engineering’s chassis dynomometer, the script files were downloaded to an agostec XBus-Simulator, which was mounted as a black box into the racing car. This system carries out it functions invisibly, yet effectively, during the qualifying and racing itself.
Kvaser’s Memorator datalogger is also used to collect data during racing or during test laps. With a combination of GPS tracking and CAN bus data – which includes speed, rpm, pedal position, position of throttle flap, gearbox information and fuel consumption (more information than an OBD-II tool will make available) – the driver has plenty of information to analyze each lap for improvement purposes.
The primary challenge of 24 hour racing compared to other motor sport disciplines is to make the car very stable and reliable for such a long term run. The car should have the maximum power and the minimum fuel consumption to be effective and efficient throughout the race. So the ECU has to be well adjusted to the engine and all components need to be able to withstand high mechanical wear. Notably, the results Racing Team Bernd Kleeschulte’s team have achieved have been impressive, with the team winning the DMV Yokohama GreenTec Cup 2009, a point-based assessment of performance across different racing series that has been designed for purely eco-friendly cars.
MTO Engineering chose Kvaser hardware because of its high performance and ease of use, as well as its stability in what can be a very rough environment. Another plus point is Kvaser’s support for a wide variety of software tools. In addition, agostec recommends Kvaser product when providing engineering consultancy, often building it into complete measurement systems for customers. “Working with Kvaser allows us to provide excellent support for CAN and LIN applications, enabling us to build a strong position in the German market,” concluded Gosling.