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arXiv · 2006.00811

Time Variable Minimum Torque Trajectory Optimization for Autonomous Excavator

Yajue Yang·Jia Pan·Pinxin Long·Xibin Song·Liangjun Zhang
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Abstract

In this paper, we present a minimal torque and time variable trajectory optimization method for autonomous excavator considering the soil-tool interaction. The method formulates the excavation motion generation as a trajectory optimization problem and takes into account geometric, kinematic and dynamics constraints. To generate time-efficient trajectory and improve the overall optimization efficiency, we propose a time variable trajectory optimization mechanism so that the time intervals between the keypoints along the trajectory subject to the optimization. As a result, the method uses few keypoints and reduces the total number of optimization variables. We further introduce a soil-tool interaction force model, which considers the geometric shape of the bucket and the physical properties of the soil. The experimental result on a high fidelity dynamic simulator shows our method can generate feasible trajectories, which satisfy excavation task constraints and are adaptive to different soil conditions.

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Yajue Yang, Jia Pan, Pinxin Long, Xibin Song, Liangjun Zhang. 2020-06-01. Time Variable Minimum Torque Trajectory Optimization for Autonomous Excavator. https://arxiv.org/abs/2006.00811

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