MASTER THESIS ADAPTIVE SLIP BASED CONTROL ALLOCATION

Master Thesis Adaptive Slip Based Control Allocation Location: Göteborg, SE, 417 15 Position Type: Student Transport is at the core of modern society. Imagine using your expertise to shape sustainable transport and infrastructure solutions for the future? If you seek to make a difference on a global scale, working with next-gen technologies and the sharpest collaborative teams, then we could be a perfect match. Master Thesis Proposal - Adaptive Slip Based Control Allocation of BEV Combinations with the Safe State Limits Obtained from the Phase Portraits Trucks with different trailer combinations can have several motion actuators that can be used for controlling the desired vehicle motions. The number of motion actuators such as steerable axles, mechanical brakes, and auxiliary brakes in combination with available powertrain actuators exceeds the number of controlled motions, so-called “over-actuation”. This allows several feasible solutions to achieve the desired longitudinal, lateral, yaw, and roll motion of each unit within the vehicle combination. One way to solve the over-actuation is to use Control Allocation (CA) within the control system. Allocation of global longitudinal force requests into different units can be done by considering the safety and energy efficiency: Safety : Allocation of very large braking or propulsion forces on driven axles, while keeping most of the other axles unbraked or unpropelled may cause yaw instabilities. As an example, if the tractor drive axle is (regeneratively) braked too much in a slippery curve, keeping all other axles unbraked may cause “jackknifing”. The control allocation algorithm should allocate forces in a safe way, which leads to no yaw instability. Energy Efficiency : Even if only one unit is electrified, energy efficiency is an important concern. For example, if only the tractor is electrified, but the trailer is conventional (non-electrified), most of the braking should be done in a regenerative way, which means braking only the driven axle of the tractor. If more than one unit is propelled, then optimal force distribution may be different, for different speeds and different force requests. Control allocation is mostly performed with physical model-based optimization methods. In this thesis, it is aimed to obtain the safe state limits for the electric tractor and electric semitrailer combination, where both units can both propel and regeneratively brake. The advantage of electric powertrains is that the controllers can request a certain amount of torque from the electric machines, while also requiring the longitudinal slips to be below a certain limit. The thesis work will require control theory, vehicle dynamics, and signal processing skills. Interest in mathematical modeling can be seen as a benefit. The thesis is recommended for two students with a control analysis profile with good mathematical skills. Thesis start date: Jan 2025. References [1]. Uhlén, K., Nyman, P., Eklöv, J., Laine, L., Kati, M. and Fredriksson, J., “Coordination of Actuators for an A-double Heavy Vehicle Combination”, 17th International IEEE Conference on Intelligent Transportation Systems, 2015. [2]. Hjelte Ulmehag R., “Energy management for a tractor and semitrailer combination using control allocation”, Master thesis, Chalmers, 2016. [3] Axel Hansson, Erik Andersson, Leo Laine, Maliheh Sadeghi Kati, Umur Erdinc and Mats Jonasson, Control envelope for limiting actuation of electric trailer in tractor-semitrailer combination, to be presented in ITSC 2022 Conference, October 8-12, in Macau, China, 2022. [4] U. Erdinc, M. Jonasson, M. S. Kati, L. Laine, B. Jacobson, and J. Fredriksson, ”Yaw stability control of vehicles using a slip polytope validated with real tests,” 16th International Symposium on Advanced Vehicle Control, Milan, Italy, Sep. 2024. We value your data privacy and therefore do not accept applications via mail. Who we are and what we believe in Our focus on Inclusion, Diversity, and Equity allows each of us the opportunity to bring our full authentic self to work and thrive by providing a safe and supportive environment, free of harassment and discrimination. Applying to this job offers you the opportunity to join Volvo Group . Every day, across the globe, our trucks, buses, engines, construction equipment, financial services, and solutions make modern life possible. #J-18808-Ljbffr