Thesis - Teknisk Design

3.2 SECOND QUESTION:Which haptic feedback technology is thebest one for in-vehicle touch screens?The following conclusions are extracted from the realization of the table 2.2 and 2.3.A variation of the first one could be found below, table 3.3. The key properties fromeach technology are highlighted in the same way it has been done before. Thereare some points that should be taken into consideration when choosing one of thetechnologies previously presented for an in-vehicle touch screen.First of all, the location of the touch screen has to be present; it will be fixed inthe dashboard of the car. Lots of efforts have been done in order to reduce car’sengine vibration, and having a new device in the car making the dashboard vibratewill not help that purpose. Also it can produce noise related to the movement in afixed place even if it is isolated. These are the main reasons why a full body tactiledisplay is not useful for an in-vehicle touch screen. Another impediment related tofixed position of the touch screen is that you cannot hold it so the feedback must bein the front of the device. Ultrasonic air pressure wave’s feedback, base its use on thefact that the user is holding the device and so the feedback on the back can besensed. Even if the feedback could be installed in the front of the device, forexample in the edges of the touch screen, the waves created to be the hapticfeedback could conflict with the functioning of the selected touch screen’stechnology.A fact that has been stressed all along the thesis is that the purpose ofincluding haptic feedback is to create a richer representation of the interaction witha touch screen. That means that the interaction should be a combination of everypossible stimuli, therefore the touch screen has to be able to produce audio andvisual feedback too, whose are already included in touch screens. One of thetechnologies presented above has the inconvenient of degrading and deformingthe images in the surface of the touch screen. This technology is the texture surface.It has other inconvenient, poor range of haptic feedback. However, it would be agreat idea to use the principle in which is based to produce acceleration feedbackin the others technologies.Even though “touch click” haptic feedback´s technology has a poor range ofhaptic feedbacks, it introduce a differentiation between navigation and activation.This property is really interesting but due to its lack of complexity it is impossible to useit alone. Moreover, people will still be looking to the screen while navigating becauseit does not include navigation haptic feedback. Then, “touch click” could be usedas a complementary haptic feedback to any of the others already mentioned.To end this discussion, one of the main reasons to include haptic feedback intouch screen must be taken into consideration; increasing people’s security whiledriving. As said in the last chapters, driver’s vision demanding is one of the main28