Conjoined collaborative robots, functioning as supernumerary robotic bodies (SRBs), can enhance human load tolerance abilities. However, in tasks involving physical interaction with humans, users may still adopt awkward, non-ergonomic postures, which can lead to discomfort or injury over time. In this paper, we propose a novel control framework that provides kinesthetic feedback to SRB users when a non-ergonomic posture is detected, offering resistance to discourage such behaviors. This approach aims to foster long-term learning of ergonomic habits and promote proper posture during physical interactions. To achieve this, a virtual fixture method is developed, integrated with a continuous, online ergonomic posture assessment framework. Additionally, to improve coordination between the operator and the SRB, which consists of a robotic arm mounted on a floating base, the position of the floating base is adjusted as needed. Experimental results demonstrate the functionality and efficacy of the ergonomics-driven control framework, including two user studies involving practical loco-manipulation tasks with 14 subjects, comparing the proposed framework with a baseline control framework that does not account for human ergonomics.

翻译：作为超数机器人身体（SRBs）的联合协作机器人能够增强人类的负载承受能力。然而，在涉及与人体进行物理交互的任务中，用户仍可能采取别扭、不符合人机工程学的姿态，长期如此可能导致不适或损伤。本文提出了一种新颖的控制框架，当检测到非人机工程学姿态时，该框架向SRB用户提供动觉反馈，施加阻力以阻止此类行为。此方法旨在促使人机工程学习惯的长期学习，并在物理交互过程中倡导正确的姿态。为实现这一目标，我们开发了一种虚拟夹具方法，并与一个连续的、在线的人机工程学姿态评估框架相集成。此外，为了提高操作者与SRB（由一个安装在浮动基座上的机械臂构成）之间的协调性，浮动基座的位置会根据需要进行调整。实验结果证明了该人机工程学驱动控制框架的功能和有效性，其中包括两项涉及14名受试者进行实际移动操作任务的用户研究，并将所提出的框架与一个不考虑人机工程学的基线控制框架进行了比较。