Evaluation of drawing on 3D surfaces with haptics

We describe experiments for evaluating the speed and accuracy of a haptic drawing interface, particularly in terms of the effects of changing two haptic characteristics the magnitude of the friction force and the use of smooth, interpolated-normal force shading in combination with the effect of stereo displays and shadows. Because surface geometry affects the sense of touch, we studied the efficacy of the haptic interface in the context of varying geometric characteristics of the surface drawing task. We also found that stereo displays, in combination with haptics, can provide additional benefits for drawing in terms of reducing error and increasing speed for the drawing task. So the decision to introduce shadows in a VR system should be considered in the context of the expected task mix.