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arXiv · 2002.06874

On sensing-aware model predictive path-following control for a reversing general 2-trailer with a car-like tractor

Oskar Ljungqvist·Daniel Axehill·Henrik Pettersson
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Abstract

The design of reliable path-following controllers is a key ingredient for successful deployment of self-driving vehicles. This controller-design problem is especially challenging for a general 2-trailer with a car-like tractor due to the vehicle's structurally unstable joint-angle kinematics in backward motion and the car-like tractor's curvature limitations which can cause the vehicle segments to fold and enter a jackknife state. Furthermore, advanced sensors with a limited field of view have been proposed to solve the joint-angle estimation problem online, which introduce additional restrictions on which vehicle states that can be reliably estimated. To incorporate these restrictions at the level of control, a model predictive path-following controller is proposed. By taking the vehicle's physical and sensing limitations into account, it is shown in real-world experiments that the performance of the proposed path-following controller in terms of suppressing disturbances and recovering from non-trivial initial states is significantly improved compared to a previously proposed solution where the constraints have been neglected.

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Oskar Ljungqvist, Daniel Axehill, Henrik Pettersson. 2020-02-17. On sensing-aware model predictive path-following control for a reversing general 2-trailer with a car-like tractor. https://arxiv.org/abs/2002.06874

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