Modular Adaptive Policy Selection for Multi-Task Imitation Learning through Task Division

TL;DR

This paper presents a modular approach to multi-task imitation learning that adaptively divides tasks into shared and task-specific sub-behaviours, reducing the need for extensive demonstrations and improving performance.

Contribution

It introduces proto-policies as modules with an adaptive selector to effectively partition tasks into shared and task-specific components, enhancing multi-task learning.

Findings

Improves accuracy over single-task and existing multi-task methods

Effectively divides tasks into shared and specific sub-behaviours

Outperforms state-of-the-art meta-learning agents

Abstract

Deep imitation learning requires many expert demonstrations, which can be hard to obtain, especially when many tasks are involved. However, different tasks often share similarities, so learning them jointly can greatly benefit them and alleviate the need for many demonstrations. But, joint multi-task learning often suffers from negative transfer, sharing information that should be task-specific. In this work, we introduce a method to perform multi-task imitation while allowing for task-specific features. This is done by using proto-policies as modules to divide the tasks into simple sub-behaviours that can be shared. The proto-policies operate in parallel and are adaptively chosen by a selector mechanism that is jointly trained with the modules. Experiments on different sets of tasks show that our method improves upon the accuracy of single agents, task-conditioned and multi-headed multi-task agents, as well as state-of-the-art meta learning agents. We also demonstrate its ability to autonomously divide the tasks into both shared and task-specific sub-behaviours.