Institute for Production Engineering and Forming Machines, Technical University of Darmstadt, 64287 Darmstadt, Germany.
Sensors (Basel). 2021 Jun 15;21(12):4104. doi: 10.3390/s21124104.
In this paper we present a novel, cost-effective camera-based multi-axis force/torque sensor concept for integration into metallic load-bearing structures. A two-part pattern consisting of a directly incident and mirrored light beam is projected onto the imaging sensor surface. This allows the capturing of 3D displacements, occurring due to structure deformation under load in a single image. The displacement of defined features in size and position can be accurately analyzed and determined through digital image correlation (DIC). Validation on a prototype shows good accuracy of the measurement and a unique identification of all in- and out-of-plane displacement components under multiaxial load. Measurements show a maximum deviation related to the maximum measured values between 2.5% and 4.8% for uniaxial loads (Fx, Fy,Fz,Mz) and between 2.5% and 10.43% for combined bending, torsion and axial load. In the course of the investigations, the measurement inaccuracy was partly attributed to the joint used between the sensor parts and the structure as well as to eccentric load.
本文提出了一种新颖的、具有成本效益的基于相机的多轴力/扭矩传感器概念，可集成到金属承重结构中。一个由直接入射和反射光束组成的两部分图案被投射到成像传感器表面上。这使得可以在单个图像中捕获由于负载下结构变形而产生的 3D 位移。通过数字图像相关（DIC）可以准确分析和确定尺寸和位置定义特征的位移。在原型上的验证表明，测量具有良好的精度，并且可以在多轴负载下唯一识别所有面内和面外位移分量。测量结果显示，对于单轴负载（Fx、Fy、Fz、Mz），最大偏差与最大测量值之间的最大偏差在 2.5%至 4.8%之间，对于弯曲、扭转和轴向负载的组合，最大偏差与最大测量值之间的最大偏差在 2.5%至 10.43%之间。在研究过程中，部分测量误差归因于传感器部件与结构之间的接头以及偏心负载。
