Design of Versatile and Low-Cost Shaft Sensor for Health Monitoring

Virtually every mechanized form of transportation, power generation system, industrial equipment, and robotic system has rotating shafts. As the shaft is often the main means of mechanical power transmission, measuring the torque, speed, vibration, and bending of the shaft can be used in many cases to access device performance and health and to implement controls. This paper proposes a shaft sensor that measures all of these phenomena with reasonable accuracy while having a low cost and simple installation process. This sensor transfers strain from the shaft and amplifies it to increase sensitivity. Furthermore, this sensor requires no components to be in the stationary reference frame, allowing the entire device to rotate with the shaft. A prototype is presented. Experimental results illustrate the effectiveness of the proposed system.