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Barbapoil
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Barbapoil
Last weekend we used XMR for the first time as a simulator for the MHRT car project. We have been working for more than a month with Eugene, the developper to get the car and the track modelized in order to perform the series of test intended. After much physics tuning and car data inserted into Vehicle Physics, the physic editor of XMR, we had reach the maximum of fidelity possible. It was now time to see how the car would drive. The setup used to perform the trials is a custom built racing cockpit with G25 steering wheel and 52 inches flat screen with 500 watts audio surround system. More than enough to get a good immersion into a race car at this point.
The idea behind simulating the car in XMR was to test different powertrain and drivetrain configurations. It gave us a rough idea of the way the car would perform on an endurance event around an autocross track. The XMR team managed to recreate a track similar to the 2008 Formula Hybrid endurance track, on wich 24 different drivetrains were tested. Each drivetrain were runned for 10 to 20 laps, with fast laps starting around the 6th or 7th lap when the tire temperature was good enough. The variation of slow and fast corners then gave us an idea of how well each different gear ratios and power outputs would handle the track. Slow laps were timed at around 37.5 sec. and fast laps at 35 sec. 10 drivetrains were then selected and rerunned with tweaked suspensions to suit either high power or high torque.
After 850 km. of trials, the data collected in the telemetry will now be analyzed and the drive cycles of the best laps will be inserted into another powertrain simulation. This will calculate the energy needed vs the energy available, it will also simulate the increase in temperature of the electric motors. At the end of this serie of test, a few drivetrains will be selected. They might not be the fastest, but they will be usable in relation to the stored energy and the safe working temperatures of the powertrain.
According to Albert Matthews from the MHRT team, this kind of use of a racing simulation has never been done before at this level of race car design. With a budget under 10 000 $ and without enough time to test drive the car before the competition, alternative ways of simulating powertrains are gold. It can not only prevent dramatic failures of the electric motors, but also optimized the performance by knowing the safe margin of use. This way, the car will run in the 90% + of its capabilities. Previous ways of simulating and testing the powertrain could only permit conservative use of power because the team could never afford replacing expensive electric motors cositng around 1000$ each.
XMR could go a step further by simulating the whole hybrid powertrain and would this way allow to know at a given ambiant temperature how the electric motors would cool down and how much more power could be given to them. The possibilities are immense and the tought of such a simulation extremly interesting for whoever is into using driving simulations to design and tune race cars.
After the past months developping the MHRT car into XMR, I can only say bravo and thank you to Eugene Cojocar, who took a lot of his time to answer our demands and make this project a reality. The Formula Hybrid competition will be held in May. Until then, we hope to make a better use of XMR with the new release coming soon and the Matlab/Simulink simulations data available at that point.
www.formula-hybrid.org
formulahybrid.mcgill.ca/
The idea behind simulating the car in XMR was to test different powertrain and drivetrain configurations. It gave us a rough idea of the way the car would perform on an endurance event around an autocross track. The XMR team managed to recreate a track similar to the 2008 Formula Hybrid endurance track, on wich 24 different drivetrains were tested. Each drivetrain were runned for 10 to 20 laps, with fast laps starting around the 6th or 7th lap when the tire temperature was good enough. The variation of slow and fast corners then gave us an idea of how well each different gear ratios and power outputs would handle the track. Slow laps were timed at around 37.5 sec. and fast laps at 35 sec. 10 drivetrains were then selected and rerunned with tweaked suspensions to suit either high power or high torque.
After 850 km. of trials, the data collected in the telemetry will now be analyzed and the drive cycles of the best laps will be inserted into another powertrain simulation. This will calculate the energy needed vs the energy available, it will also simulate the increase in temperature of the electric motors. At the end of this serie of test, a few drivetrains will be selected. They might not be the fastest, but they will be usable in relation to the stored energy and the safe working temperatures of the powertrain.
According to Albert Matthews from the MHRT team, this kind of use of a racing simulation has never been done before at this level of race car design. With a budget under 10 000 $ and without enough time to test drive the car before the competition, alternative ways of simulating powertrains are gold. It can not only prevent dramatic failures of the electric motors, but also optimized the performance by knowing the safe margin of use. This way, the car will run in the 90% + of its capabilities. Previous ways of simulating and testing the powertrain could only permit conservative use of power because the team could never afford replacing expensive electric motors cositng around 1000$ each.
XMR could go a step further by simulating the whole hybrid powertrain and would this way allow to know at a given ambiant temperature how the electric motors would cool down and how much more power could be given to them. The possibilities are immense and the tought of such a simulation extremly interesting for whoever is into using driving simulations to design and tune race cars.
After the past months developping the MHRT car into XMR, I can only say bravo and thank you to Eugene Cojocar, who took a lot of his time to answer our demands and make this project a reality. The Formula Hybrid competition will be held in May. Until then, we hope to make a better use of XMR with the new release coming soon and the Matlab/Simulink simulations data available at that point.
www.formula-hybrid.org
formulahybrid.mcgill.ca/