Quantifying Assistive Robustness Via the Natural-Adversarial Frontier

📄 arXiv: 2310.10610v1 📥 PDF

作者: Jerry Zhi-Yang He, Zackory Erickson, Daniel S. Brown, Anca D. Dragan

分类: cs.AI, cs.LG, cs.RO

发布日期: 2023-10-16


💡 一句话要点

提出RIGID方法以量化机器人助理的鲁棒性

🎯 匹配领域: 支柱二:RL算法与架构 (RL & Architecture) 支柱七:动作重定向 (Motion Retargeting) 支柱八:物理动画 (Physics-based Animation)

关键词: 鲁棒性评估 人机交互 对抗扰动 强化学习 自然-对抗边界 机器人策略 智能助理

📋 核心要点

  1. 核心问题:现有方法主要依赖对抗扰动来测量鲁棒性,但这可能导致错误的评估,无法反映真实的人机交互情况。
  2. 方法要点:论文提出RIGID方法,通过训练对抗性人类策略,构建自然-对抗边界,分析自然性与机器人性能之间的权衡。
  3. 实验或效果:在Assistive Gym任务中,RIGID能够有效识别鲁棒性,并揭示人机交互中的失败案例,提供有意义的鲁棒性度量。

📝 摘要(中文)

本研究旨在构建能够有效辅助人类的机器人策略,但由于人类在测试时的不可预测行为,可能导致机器人在训练分布之外的交互中出现失败。现有的对抗扰动方法可能无法准确反映鲁棒性,因为它们可能对应于不太可能在自然交互中发生的人类动作。为此,本文提出了RIGID方法,通过构建自然-对抗边界,分析人类策略在自然性与机器人性能之间的权衡,从而更全面地捕捉鲁棒性。实验表明,RIGID能够有效识别鲁棒性,并揭示人机交互中的潜在失败案例。

🔬 方法详解

问题定义:本研究旨在解决机器人在与人类交互时的鲁棒性评估问题。现有方法主要依赖对抗扰动,但这些扰动可能不符合自然交互的实际情况,导致鲁棒性评估不准确。

核心思路:论文提出的RIGID方法通过构建自然-对抗边界,分析人类策略在自然性与机器人性能之间的权衡,从而更全面地捕捉鲁棒性。这种设计能够更好地反映真实的交互场景。

技术框架:RIGID方法的整体架构包括训练对抗性人类策略的模块,该模块通过最小化机器人奖励与模拟人类行为的判别器之间的权衡来构建自然-对抗边界。

关键创新:RIGID的主要创新在于引入了自然-对抗边界的概念,提供了一种新的鲁棒性评估方式,与传统的对抗扰动方法本质上不同,能够更好地反映人机交互中的真实情况。

关键设计:在RIGID中,关键参数包括对抗性人类策略的训练损失函数,该函数综合考虑了机器人奖励和人类行为的相似度。此外,使用的判别器网络结构经过优化,以提高人类行为的模拟精度。

🖼️ 关键图片

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📊 实验亮点

实验结果表明,RIGID方法在Assistive Gym任务中能够有效识别鲁棒性,且与现有方法相比,提供了更准确的鲁棒性度量。通过对比分析,RIGID能够揭示出在专家对抗交互和自然用户交互中难以发现的失败案例,显示出其在实际部署中的预测能力。

🎯 应用场景

该研究的潜在应用领域包括人机协作机器人、智能助理以及其他需要与人类进行自然交互的机器人系统。通过提高机器人在复杂环境中的鲁棒性,能够显著提升其实际应用价值,减少因意外交互导致的失败。未来,这一方法可能推动更安全、更高效的人机协作技术的发展。

📄 摘要(原文)

Our ultimate goal is to build robust policies for robots that assist people. What makes this hard is that people can behave unexpectedly at test time, potentially interacting with the robot outside its training distribution and leading to failures. Even just measuring robustness is a challenge. Adversarial perturbations are the default, but they can paint the wrong picture: they can correspond to human motions that are unlikely to occur during natural interactions with people. A robot policy might fail under small adversarial perturbations but work under large natural perturbations. We propose that capturing robustness in these interactive settings requires constructing and analyzing the entire natural-adversarial frontier: the Pareto-frontier of human policies that are the best trade-offs between naturalness and low robot performance. We introduce RIGID, a method for constructing this frontier by training adversarial human policies that trade off between minimizing robot reward and acting human-like (as measured by a discriminator). On an Assistive Gym task, we use RIGID to analyze the performance of standard collaborative Reinforcement Learning, as well as the performance of existing methods meant to increase robustness. We also compare the frontier RIGID identifies with the failures identified in expert adversarial interaction, and with naturally-occurring failures during user interaction. Overall, we find evidence that RIGID can provide a meaningful measure of robustness predictive of deployment performance, and uncover failure cases in human-robot interaction that are difficult to find manually. https://ood-human.github.io.