DOI: 10.1109/TIE.2026.3661007

Abstract

This study presents a noncontact inductive displacement sensor based on flexible printed circuit technology for fabricating a simplified planar folded coil structure. The sensor primarily comprises a cantilever base integrated with excitation coils and a U-shaped base equipped with receiving coils. As relative motion occurs between the two bases, the mutual inductance between the excitation and receiving coils varies accordingly. By analyzing and processing the two orthogonal induced signals from the receiving coils, precise displacement measurement along the X-axis can be achieved. The adoption of a periodic grid-like coil structure enables effective range scalability. Furthermore, through the implementation of a bilateral compensation design and optimized coil arrangement, the sensor demonstrates strong immunity to disturbance errors caused by unintended displacements within certain ranges along the Y and Z directions. These features highlight its robustness and potential for practical applications. The experimental results demonstrate that the sensor prototype achieves a resolution of 6.1 nmrms over a measurement range of 25 mm, with a measurement error below 5.6 µm and a 3σ repeatability better than 2.7 µm.

图片摘要

图一：传感器结构示意图：（a）整体结构图；（b）该结构的侧视图；以及（c）线圈设计的俯视图。

图二：传感器原型的解决方案测试：（a）静态噪声测量结果；以及（b）阶跃响应测试结果。

亮点

  本文重点介绍了高精度定位系统中，特别是大口径分段镜望远镜的执行器中，对毫米级范围内纳米级分辨率位移测量的需求。与大范围、高精度光栅尺和激光位移传感器等传统解决方案不同，本研究提出了一种非接触式、大范围感应位移传感器。该设计解决了电感传感器在分辨率方面的典型局限性，同时结合了双边补偿结构和优化的线圈设计，实现了对横向干扰误差具有很强抵抗力的位移测量，从而展示了广泛的应用潜力。