In plain words: Instead of guessing many action plans and keeping the best, this planner tweaks actions directly by running the learned world model backwards to see what to change. With limited training data, it matched or beat those guess-and-pick planners on most tasks.
Abstract · Gradient-based Planning with World Models
The enduring challenge in the field of artificial intelligence has been the control of systems to achieve desired behaviours. While for systems governed by straightforward dynamics equations, methods like Linear Quadratic Regulation (LQR) have historically proven highly effective, most real-world tasks, which require a general problem-solver, demand world models with dynamics that cannot be easily described by simple equations. Consequently, these models must be learned from data using neural networks. Most model predictive control (MPC) algorithms designed for visual world models have traditionally explored gradient-free population-based optimisation methods, such as Cross Entropy and Model Predictive Path Integral (MPPI) for planning. However, we present an exploration of a gradient-based alternative that fully leverages the differentiability of the world model. In our study, we conduct a comparative analysis between our method and other MPC-based alternatives, as well as policy-based algorithms. In a sample-efficient setting, our method achieves on par or superior performance compared to the alternative approaches in most tasks. Additionally, we introduce a hybrid model that combines policy networks and gradient-based MPC, which outperforms pure policy based methods thereby holding promise for Gradient-based planning with world models in complex real-world tasks.
Jyothir S, Siddhartha Jalagam, Yann LeCun, Vlad Sobal
arXiv:2312.17227 · cs.LG, cs.AI · submitted Dec 28, 2023
abstract · pdf · html
Making plans when dealing with incomplete or missing information requires strategy and adaptability, and multiple routes to a moving target. How hard would a hunting game be for these models?