Up until recently I was an owner of a hybrid car from one of the leading car manufacturers. The mechanical side of the car was good but I always had some serious doubts about the car’s cockpit. In particular, the touch screen mounted squarely in the middle of the dashboard, presumably to be equally accessible to the driver and the front passenger.
Touch screens are good and certainly have their place in various products, but the way the screen was used in this particular car presented more of a safety hazard than a feature. The biggest problem with the touch screen was that it was flat and did not have any distinguishing features on its surface. The second problem was that it reacted to a mere touch of a finger (which is not surprising given its name -- touch screen). Combine these two things together and you get a combination which forces the driver to watch the screen while pressing the desired command. And that is a very bad thing to do when you are driving.
With physical buttons it is easier. After a while you remember that the first button on the right is the radio, the one next to it is the temperature control and so on. This enables you to go over the buttons with your fingers until you find the right one and then press it, and you can do all of that without taking eyes off the road. If you are pedantic you may say that, while fumbling about with your hand, your focus becomes narrower, you start experiencing tunnel vision and may miss things that are happening at the edge of your vision. That is all true but you can still keep watching where you are driving and not be forced to look at the screen.
Some functions can be controlled by either using the touch screen or physical buttons (or knobs and levers). That is great since you can do what you want without averting your gaze from the road. I am well aware that space on a car’s dashboard is very limited and there are only so many buttons you can add before people get the impression they are piloting a jet fighter rather than driving a car and give up in desperation. For that reason, car manufacturers are placing some of the control on the steering wheel. Such buttons can be easily reached by extending your finger while still gripping the steering wheel.
The question then is what commands will the manufacturer place on the steering wheel, and this manufacturer decided to place (among other things) climate controls there. By using them you can control the temperature and also turn on heating of the windshield and glass defrosting. All of this sounds very good until you try to drive down a winding road on a humid day. Change in outside temperature can cause your windshield to become foggy so you must to turn the heating on. You can do that on the touch screen, which is not the best idea as you really need to watch the road, or you can do it using the buttons on the steering wheel. The problem with that is that control buttons are one second on the left side and the next second on the right side, depending which way you turn the steering wheel. The fact that half of the time these buttons are positioned upside down does not help either.
Then again, not all functions have double commands -- physical buttons and controls on the touch screen. Some functions are only available via touch screen. If you want to use them you really must watch the screen and not the road. Now, you may say, if you are not in a position to stop the car and fiddle with the touch screen then you must do things in stages. Make the required adjustment in several steps. First select the appropriate screen and then, when road conditions allow, make a selection, and so on. It will take longer but it is safer. All good and well, but the manufacturer decided that whatever screen you choose on the touch screen, it will switch back to the default after around 7 seconds. So even if you want to take this gradual approach you must be fast or you will not be able to finish what you have started.
And please, do not get me started on the GPS in this car! I am certain that there is some logic in how you are supposed to interact with it but I was not able to comprehend it after three years.
Touch screens in the car can be useful but must be used judiciously. Forcing drivers to take their eyes off the road is never a good idea, so a great deal of consideration must be put into what function a touch screen will have. Advances are being made in haptics so that touch screens can provide tactile feedback but we are not there yet. Until then, please, car manufacturers, do not put drivers into more dangers than they already are.