Evaluating Multi-Channel Vibrational Feedback Arrays in a Digit Discrimination Task

In recent years manipulators and grippers have become more advanced., allowing for more nuanced interactions with the environment. In order to take advantage of the benefits that this can provide in teleoperation., methods for providing closed-loop tactile feedback to the operator must be developed. This paper presents the results from a series of experiments into the design space of vibrotactile feedback arrays for multi-fingered end-effectors., from a user-centred perspective. These experiments were conducted over two sessions., each with 11 healthy subjects. The first session investigated the general shape of the array by comparing three different morphologies., while the second session investigated the effects of tactor spacing., and of kinesthetic feedback on the learning process. The results from these studies indicate several key design choices in multi-channel vibrotactile arrays for teleoperation: The array must have features that are distinct and easy to reference., larger displacements between tactors is preferable with a 40mm separation outperforming 25mm by on average 10% (p=0.004)., a method to disambiguate multiple finger contact is necessary., and that the training process heavily impact the resultant performance with the device (p=0.016).