Bio-Inspired Robotics Laboratory, Institute of Robotics and Intelligent Systems, Department of Mechanical and Process Engineering, ETH Zürich, Zürich, Switzerland.
PLoS One. 2013 Dec 26;8(12):e84090. doi: 10.1371/journal.pone.0084090. eCollection 2013.
Despite the widespread use of sensors in engineering systems like robots and automation systems, the common paradigm is to have fixed sensor morphology tailored to fulfill a specific application. On the other hand, robotic systems are expected to operate in ever more uncertain environments. In order to cope with the challenge, it is worthy of note that biological systems show the importance of suitable sensor morphology and active sensing capability to handle different kinds of sensing tasks with particular requirements.
This paper presents a robotics active sensing system which is able to adjust its sensor morphology in situ in order to sense different physical quantities with desirable sensing characteristics. The approach taken is to use thermoplastic adhesive material, i.e. Hot Melt Adhesive (HMA). It will be shown that the thermoplastic and thermoadhesive nature of HMA enables the system to repeatedly fabricate, attach and detach mechanical structures with a variety of shape and size to the robot end effector for sensing purposes. Via active sensing capability, the robotic system utilizes the structure to physically probe an unknown target object with suitable motion and transduce the arising physical stimuli into information usable by a camera as its only built-in sensor.
CONCLUSIONS/SIGNIFICANCE: The efficacy of the proposed system is verified based on two results. Firstly, it is confirmed that suitable sensor morphology and active sensing capability enables the system to sense different physical quantities, i.e. softness and temperature, with desirable sensing characteristics. Secondly, given tasks of discriminating two visually indistinguishable objects with respect to softness and temperature, it is confirmed that the proposed robotic system is able to autonomously accomplish them. The way the results motivate new research directions which focus on in situ adjustment of sensor morphology will also be discussed.
尽管传感器已广泛应用于机器人和自动化系统等工程系统，但常见的模式是将具有特定应用的固定传感器形态进行定制。另一方面，机器人系统预计将在更加不确定的环境中运行。为了应对这一挑战，值得注意的是，生物系统展示了合适的传感器形态和主动传感能力的重要性，以处理具有特殊要求的不同类型的传感任务。
本文提出了一种机器人主动传感系统，该系统能够在现场调整其传感器形态，以便用理想的传感特性感知不同的物理量。所采用的方法是使用热塑性粘合剂材料，即热熔胶（HMA）。结果表明，HMA 的热塑性和热粘性特性使系统能够为传感目的，将各种形状和尺寸的机械结构重复地制造、附着和拆卸到机器人末端执行器上。通过主动传感能力，机器人系统利用结构以合适的运动对未知目标物体进行物理探测，并将产生的物理刺激转换为其唯一内置相机可用的信息。
结论/意义：基于两个结果验证了所提出系统的有效性。首先，确认了合适的传感器形态和主动传感能力使系统能够用理想的传感特性感知不同的物理量，即柔软度和温度。其次，在区分两个在柔软度和温度方面无法视觉区分的物体的任务中，确认了所提出的机器人系统能够自主完成这些任务。还将讨论结果激励新的研究方向的方式，这些方向侧重于传感器形态的现场调整。
