永久磁化を利用したロボット関節用円盤型磁歪トルクセンサ
A Disk-Shaped Magnetoelastic Torque Sensor for Robotic Joints Using Permanent Magnetization
ロボット関節に組み込める厚さ約1cmの円盤型磁歪トルクセンサを開発し、4つの磁力計で応力による磁場変化を測定、磁気シールドで外乱を低減して50Nmフルスケールで1.34%の精度を達成した。
著者: Bruno Brajon, Enrico Gasparin, Nicole Yazigy, Lisa Salamin, Florian Copt, Guzmán Borque Gallego, Elias Klauser, Gaël Close
分類: cs.RO, eess.SY
原文アブストラクト
Direct torque sensing is a growing need in the robotics community to enable precise control and interactions where torque estimation from motor current is not sufficient. This paper presents a novel disk-shaped magnetoelastic torque sensor with a compact axial envelope of about 1 cm, suitable for integration in robotic joints. A four-magnetometer architecture is used to measure the field modulated by the stress affecting a narrow magnetized region while rejecting the effects of parasitic cross forces. A custom-designed magnetic shield enhances the torque sensitivity while reducing the external stray fields by a factor 7x. The device measures the torque with an accuracy of 1.34 %FS relative to the 50 Nm full scale (FS). The paper details the development of the sensor through the mechanical design, the magnetization procedure, and the experimental validation. The results demonstrate the potential of the proposed sensor for robotic applications.