Mercedes Hyperscreen and the current issue with passenger screens

At CES 2021, Mercedes introduced Hyperscreen, a three-screen display stretching across the entire dashboard. Besides looking very sci-fi and doing away with all physical inputs, it also has a passenger display for the co-pilot. For me, as a UX researcher with over 10 years of experience evaluating car HMIs, the first question that came to mind was “Did they actually think about what passengers need and want before building this?”.

You may wonder why, with such an exciting new feature, this would be the first thing I think about. It is because of my research on two of the cars currently available in Germany with passenger displays: the Porsche Taycan and the Honda e.

Porsche Taycan

I saw the Porsche Taycan at IAA 2019 and later got the chance to evaluate it in detail. In the Taycan, there is a selection of options from the driver’s main menu on the passenger’s screen as well. This means that the passenger can do most of the things the driver can.

When seeing this, one colleague asked me if this means his 13-year-old daughter could put on Justin Bieber without him having any control over it. “Yes, she can”, I answered to his dismay. Other concerns were passengers accessing family videos via USB drive or a friend browsing through a contact list comfortably from their own screen.

To be fair, the passenger display can be disabled, but the button is located to the right of the passenger display - safely out of the driver’s reach.

Honda e

More recently I got to test the Honda e. At first glance, it follows a different approach than the Porsche, but during my review I came across design execution that appears to expose a critical flaw in the engineers’ thinking.

In the Honda e, there is a clear separation of functions between the driver and the passenger; on the driver’s side, there are the options for phone, navigation, smartphone connection and a Honda personal assistant. On the passenger side, the options include FM, HDMI, general settings, and Bluetooth audio. Effectively, they went much further than Porsche by really thinking about what functions would be relevant for passenger vs. driver.

However, once you want to turn on the radio while driving without a passenger, you quickly notice the fatal flaw in the design: There is no convenient way to access these functions in the head unit. Instead, users must click through a finnicky text-scroll menu for everything that is not one of the six main options in their menu. Instead of using this cumbersome route, it feels easier to lean over to the passenger screen to access functions that Honda thought would only be relevant for the passenger. So, Honda has built a system that only works with a passenger – better plan to pick up a hitchhiker if you want to listen to music from the radio while driving.

Additionally, if you do not want the passenger to access functions in your system (there is no limit to which functions they can access here), you cannot disable the screen - so also bring a long stick to keep their hands of your ACC settings.

Untapped opportunties

In both cars, my colleagues and I wondered why the passenger apps looked the same as the driver apps. There is no need to keep distraction low for the passenger, so why does the POI selection look as bare boned and drab as it does on the driver’s side? Why can they not see more detail, more visual information, ratings for cafés and restaurants? Many passengers want to be real co-pilots and they see their contribution to the journey in the fact that they can really go into depth because they do not have to pay attention to the road.

I am looking forward to seeing if Mercedes offers this kind of functionality for passengers – think entertainment manager for rear-seat entertainment, planning sight-seeing routes, booking hotels and seats at restaurants. It would be great to see if they thought about the different kinds of passengers in that seat. For example, who should have different access rights (from none to all)? However, from the preview I saw in the CES videos, it looks as if the passenger is at best only a “small driver”, which is a huge misconception based on what we see when we talk to real users.