Students from Chalmer’s University of Technology have used Kvaser’s Memorator to gather data for a research project that highlights how relatively simple chassis changes can result in significantly more fuel-efficient automotive designs.
The BSc final year project, which was initiated by BSR Svenska AB, set out to monitor what impact easily implemented changes to a typical automotive chassis could have on fuel consumption. BSR commissioned the project with a view to applying as many changes as are practical in an ethanol converted car, as well as incorporated into a conversion kit for a conventional car.
Kvaser partner and Technical Associate ATI Accurate Technologies loaned the students a Memorator USB CAN bus interface and CAN bus data logger, plus provided set-up advice. The project made use of ATI’s CANLab 3.0 software to record and evaluate the information gathered.
Explained Kristoffer Wilhelmsson, one of the six-strong research team from the University’s Department of Applied Mechanics: “Using a test chassis loaned by Saab Development Centre for Car Recycling, we experimented by removing the power assisted steering, changing the tyres to Michelin Energy Saver versions, raising tyre pressure and adjusting the wheel alignment to minimise rolling resistance. The combined changes led to a reduction in fuel consumption of 13% compared to the standard design, exceeding our goal of lowering fuel consumption by 10% - an impressive result from some relatively low-impact changes.”
The students needed to verify theoretical improvements in fuel consumption by measuring metrics such as speed and the amount of fuel injected over time after each chassis adjustment. They decided to run two different tests. In one, rolling resistance was measured by monitoring the distance it took for the car to come to a standstill after reaching 30km/hr and being placed into neutral. In another experiment, the impact of the different changes was investigated by driving the test vehicle at 70km/hr in opposing directions, to compensate for extraneous environmental factors such as road camber and wind resistance.
Added Wilhelmsson: “There was a lot of data to gather, but data acquisition was very simple. We easily configured the Memorator and set up trigger conditions, for example, triggering at 30km/hr and the point at which the car came to a standstill. Uploading data to the laptop via usb was very convenient too.”
The chassis study was part of a large research project undertaken by BSR that also explored the engine and aerodynamics. Noted Wilhelmsson: “We found that the most effective chassis changes were tyre related - simply raising tyre pressure from 2.2 to 3 bar was enough to realise significant gains in fuel consumption. Regarding future developments, there is an opportunity to extend the study to explore the impact of such chassis adjustments on different vehicles."