GPU-Accelerated Motion Planning of an Underactuated Forestry Crane in Cluttered Environments
Minh Nhat Vu, Gerald Ebmer, Alexander Watcher, Marc-Philip Ecker, Giang Nguyen, Tobias Glueck
TL;DR
This work addresses real-time motion planning for underactuated forestry cranes operating in cluttered environments by proposing a two-step GPU-accelerated framework. The first stage uses CMA-ES-inspired stochastic optimization with GPU-accelerated collision checking to produce a globally shortest collision-free path, while the second stage refines this path into a dynamically feasible trajectory via direct collocation that enforces system dynamics and hydraulic limits. Key contributions include fast GPU-based collision checking, a global path optimization module, and an efficient trajectory-tracking stage, with Monte Carlo simulations showing near-time (<2 s) trajectory generation and favorable consistency compared to LQR-RRT* and purely optimization-based methods. The framework enables batch trajectory generation and demonstrates substantial speedups without compromising feasibility, making it well-suited for real-time autonomous forestry crane operations in complex environments.
Abstract
Autonomous large-scale machine operations require fast, efficient, and collision-free motion planning while addressing unique challenges such as hydraulic actuation limits and underactuated joint dynamics. This paper presents a novel two-step motion planning framework designed for an underactuated forestry crane. The first step employs GPU-accelerated stochastic optimization to rapidly compute a globally shortest collision-free path. The second step refines this path into a dynamically feasible trajectory using a trajectory optimizer that ensures compliance with system dynamics and actuation constraints. The proposed approach is benchmarked against conventional techniques, including RRT-based methods and purely optimization-based approaches. Simulation results demonstrate substantial improvements in computation speed and motion feasibility, making this method highly suitable for complex crane systems.
