As robots increasingly operate in shared, safety critical environments, acting safely is no longer sufficient robots must also make their safety decisions intelligible to human collaborators. In human robot collaboration (HRC), behaviours such as stopping or switching modes are often triggered by internal safety constraints that remain opaque to nearby workers. We present a dialogue based framework for interactive explanation of safety decisions in HRC. The approach tightly couples explanation with constraint based safety evaluation, grounding dialogue in the same state and constraint representations that govern behaviour selection. Explanations are derived directly from the recorded decision trace, enabling users to pose causal ("Why?"), contrastive ("Why not?"), and counterfactual ("What if?") queries about safety interventions. Counterfactual reasoning is evaluated in a bounded manner under fixed, certified safety parameters, ensuring that interactive exploration does not relax operational guarantees. We instantiate the framework in a construction robotics scenario and provide a structured operational trace illustrating how constraint aware dialogue clarifies safety interventions and supports coordinated task recovery. By treating explanation as an operational interface to safety control, this work advances a design perspective for interactive, safety aware autonomy in HRC.

翻译：随着机器人在共享安全关键环境中的日益普及，仅保证安全操作已不再充分——机器人还必须使其安全决策被人类协作者理解。在人机协作（HRC）中，停止或切换模式等行为通常由内部安全约束触发，而这些约束对附近工人而言是模糊的。我们提出一个基于对话的框架，用于在人机协作中实现安全决策的交互式解释。该方法将解释与基于约束的安全评估紧密耦合，使对话基于与行为选择相同的状态和约束表示。解释直接从记录决策轨迹中推导得出，使用户能够针对安全干预提出因果型（“为什么？”）、对比型（“为什么不？”）和反事实型（“如果……会怎样？”）查询。反事实推理在固定的、经过认证的安全参数下以有界方式进行评估，确保交互式探索不会削弱操作保证。我们将该框架实现在一个建筑机器人场景中，并提供结构化操作轨迹，说明基于约束的对话如何阐明安全干预并支持协调任务恢复。通过将解释视为安全控制的操作接口，本研究推进了人机协作中交互式安全感知自主性的设计视角。