Copyright 2009 by Human Factors and Ergonomics Society, Inc. All rights reserved. 10.1518/107118109X12524442637020

Sensory augmentation using vibrotactile stimulation has been shown to compensate for distorted haptic feedback in tissue compliance differentiation tasks in laparoscopic surgery. This study investigated its usefulness for tumor palpation. A controlled experiment was conducted using a wearable vibrotactile device that responded with various levels of vibration signal parameters (i.e., amplitude, frequency and duty-cycle) as a function of applied force during a palpation task. Results showed that subjects were able to perform more accurately and more confidently, applying lower peak forces and smaller force ranges to make a judgment regarding the presence of an embedded structure, with vibrotactile augmentation than without. In addition, as more parameters of the vibration signal were modulated (up to three), the vibrotactile augmentation tended to be more effective, possibly due to the greater information content in the multi-parameter signal. This suggests that palpation can be improved by implementing a vibration device that is capable of multi-dimensional modulation. However, the design of the vibration device should balance the advantage of providing additional information for effective information transmission with that of signal redundancy and complexity.