School of Instrumentation Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Sensors (Basel). 2023 Jan 7;23(2):700. doi: 10.3390/s23020700.
In order to overcome the shortcomings of the traditional magnetic absolute linear displacement sensors in which cables affect the flexibility and measurement range in linear motor transmission systems, this paper proposes a novel cable-free moving magnetic grid-type long-range absolute displacement sensor. The sensor consists of a magnetic grid and a signal acquisition board. The magnetic grid is a moving component that contains two rows of permanent magnet arrays, one for relative displacement measurement and the other for the displacement interval code. The signal acquisition board is a fixed component that uses groups of two-row Hall sensor arrays for continuous absolute displacement measurement. The principle of the sensor using the 2D magnetic field signal for the relative displacement measurement is analyzed, and a measurement method based on Hall sensor arrays for coding and absolute displacement detection over cycles is proposed. Finally, a sensor prototype is fabricated and the experiments are performed. The experimental results show that the measurement resolution of the sensor is 5 μm, and the measurement accuracy is ±14.8 μm within the measurement range of 0-98.3 mm. The proposed sensor can realize continuous absolute displacement measurement over multiple cycles without cable binding.
为了克服传统磁绝对线性位移传感器在直线电机传动系统中因电缆影响灵活性和测量范围的缺点，本文提出了一种新型无缆动磁网格式长程绝对位移传感器。该传感器由磁网格和信号采集板组成。磁网格是一个移动部件，包含两排永磁体阵列，一排用于相对位移测量，另一排用于位移间隔编码。信号采集板是一个固定部件，使用多组两排霍尔传感器阵列进行连续绝对位移测量。分析了传感器利用二维磁场信号进行相对位移测量的原理，并提出了一种基于霍尔传感器阵列的编码和绝对位移检测方法，该方法可以实现超过 个周期的循环绝对位移测量。最后，制作了一个传感器原型并进行了实验。实验结果表明，传感器的测量分辨率为 5μm，在 0-98.3mm 的测量范围内，测量精度为±14.8μm。所提出的传感器可以实现多个周期的连续绝对位移测量，无需电缆束缚。
