Transporting large and heavy objects can benefit from Human-Robot Collaboration (HRC), increasing the contribution of robots to our daily tasks and reducing the risk of injuries to the human operator. This approach usually posits the human collaborator as the leader, while the robot has the follower role. Hence, it is essential for the leader to be aware of the environmental situation. However, when transporting a large object, the operator's situational awareness can be compromised as the object may occlude different parts of the environment. This paper proposes a novel haptic-based environmental awareness module for a collaborative transportation framework that informs the human operator about surrounding obstacles. The robot uses two LIDARs to detect the obstacles in the surroundings. The warning module alerts the operator through a haptic belt with four vibrotactile devices that provide feedback about the location and proximity of the obstacles. By enhancing the operator's awareness of the surroundings, the proposed module improves the safety of the human-robot team in co-carrying scenarios by preventing collisions. Experiments with two non-expert subjects in two different situations are conducted. The results show that the human partner can successfully lead the co-transportation system in an unknown environment with hidden obstacles thanks to the haptic feedback.

翻译：搬运大型重物可通过人机协作（HRC）获益，既能提升机器人对日常任务的贡献，又能降低操作人员受伤风险。该方法通常将人类协作者设定为领导者，机器人则承担跟随者角色。因此，领导者掌握环境态势至关重要。然而，搬运大型物体时，操作员的情境感知能力可能因物体遮挡环境局部而受损。本文提出一种基于触觉的新型环境感知模块，用于协作搬运框架，可向操作人员提示周围障碍物。机器人利用两个激光雷达（LIDAR）检测周边障碍物，并通过配备四个振动触觉装置的触觉腰带向操作员发出预警，反馈障碍物的位置与接近程度。该模块通过增强操作员的环境感知能力，能够通过避免碰撞提升人机团队在协同搬运场景中的安全性。实验在两种不同情境下由两名非专业受试者完成。结果表明，得益于触觉反馈，人类协作者能够在存在隐藏障碍物的未知环境中成功引导协同搬运系统。