Investigating the Effects of Mechanical Variables on the Performance of Resistive Bend Sensors Used in Digit Motion Tracking

Resistive bend sensors are commonly used in data gloves to measure finger joint angles and are favored for their durability, flexibility, and affordability. However, their performance can be affected by mechanical factors, such as the range of motion (ROM) and speed, which have yet to be fully investigated. This study aimed to systematically explore the effects of ROM and speed on the performance of resistive bend sensors, focusing on four performance indices, i.e., sensitivity, repeatability, hysteresis, and sensor relaxation. Sensors from two manufacturers, Spectra Symbol and Flexpoint, were tested across six ROMs and seven speeds. Statistical analysis was performed to find the correlation between performance indices and ROM and speed, as well as the difference between two sensors. The results showed that the performance of the two sensors is affected by ROM and speed. ROM affected the sensitivity, repeatability, and relaxation indices; however, the results were not similar across the two sensors. Speed affected the sensitivity and relaxation, with differences in the observed effects between the two sensors. Hysteresis did not show any significant correlation with either ROM or speed. Finally, the sensor’s sensitivity was observed to be dependent on the direction of movement (flexion or extension). Our experimental results suggested that comprehensive and targeted experiments are required before integrating resistive bend sensors into data gloves for different applications.