Abah Colette, Orekhov Andrew L, Johnston Garrison L H, Simaan Nabil
Department of Mechanical Engineering, Vanderbilt University, Nashville, TN 37235, USA.
IEEE Sens J. 2022 Feb 15;22(4):3585-3594. doi: 10.1109/jsen.2021.3140002. Epub 2021 Dec 31.
Safe human-robot interaction requires robots endowed with perception. This paper presents the design of a multi-modal sensory array for continuum robots, targeting operation in semi-structured confined spaces with human users. Active safety measures are enabled via sensory arrays capable of simultaneous sensing of proximity, contact, and force. Proximity sensing is achieved using time-of-flight sensors, while contact force is sensed using Hall effect sensors and embedded magnets. The paper presents the design and fabrication of these sensors, the communication protocol and multiplexing scheme used to allow an interactive rate of communication with a high-level controller, and an evaluation of these sensors for actively mapping the shape of the environment and compliance control using gestures and contact with the robot. Characterization of the proximity sensors is presented with considerations of sensitivity to lighting, color, and texture conditions. Also, characterization of the force sensing is presented. The results show that the multi-modal sensory array can enable pre and post-collision active safety measures and can also enable user interaction with the robot. We believe this new technology allows for increased safety for human-robot interaction in confined and semi-structures spaces due to its demonstrated capabilities of detecting impending collision and mapping the environment along the length of the robot. Future miniaturization of the electronics will also allow possible integration in smaller continuum and soft robots.
安全的人机交互需要具备感知能力的机器人。本文介绍了一种用于连续体机器人的多模态传感阵列的设计，目标是在半结构化受限空间内与人类用户协同操作。通过能够同时感知接近度、接触和力的传感阵列实现主动安全措施。使用飞行时间传感器实现接近度传感，而使用霍尔效应传感器和嵌入式磁体感测接触力。本文介绍了这些传感器的设计与制造、用于实现与高级控制器的交互式通信速率的通信协议和复用方案，以及对这些传感器进行评估以利用手势和与机器人的接触来主动绘制环境形状并进行柔顺控制。给出了接近传感器的特性描述，并考虑了其对光照、颜色和纹理条件的敏感性。此外，还给出了力传感的特性描述。结果表明，多模态传感阵列能够实现碰撞前和碰撞后的主动安全措施，还能实现用户与机器人的交互。我们相信，这项新技术因其具备检测即将发生的碰撞以及沿机器人长度方向绘制环境的能力，能够提高在受限和半结构化空间内人机交互的安全性。未来电子设备的小型化也将使其有可能集成到更小的连续体机器人和软体机器人中。
