A series of experiments was conducted to evaluate the operating characteristics of small DC motors that are often in tactile displays. The results indicated that these motors are reliable in terms of their frequency and amplitude of oscillation, but that the frequency varies across motors. A simulated skin material was developed to provide a substrate for evaluating the performance of the motors. There was a marked attenuation in frequency when the tactors were on this material and the surface waves could be detected 60 mm from the site of activation. These findings suggest that the spacing between tactors should be at least 60–80 mm if tactile cues are used to locate events in the environment.