Are there any drawbacks or potential dangers on using touch-sensitive instrument panels on spacecraft?

Question

Just as seen on Orion and Dragon designs (I haven't checked on other current spacecrafts), there are a lot of benefits from using touch-sensitive panels instead of traditional electrical switches.

Some benefits might be:

• Less wiring and less clutter, hence more space in the module and less weight
• Less risk of electrical/mechanical malfunction, electrical fire, etc.
• More intuitive interface
• Ability to update firmware/software
• Language translations on UI (could come in handy for multi-cultural teams)
• Many others...

Now, having said that, what could be some potential dangers or drawbacks from using this design instead of classical electrical switches?

Answer 1

If you look at the SpaceX design, you see that there are the large touch screen displays. But there are also standard physical buttons for manual controls.

As noted in the comments, while under thrust at 3-5G's a touch screen just isn't going to cut it.

Additionally, Dragon V2 is meant to have an almost entirely automated flight regime. The crew are not meant to fly the vehicle in normal cases. As a consequence the small set of physical switches are meant to be used only under exceptional circumstances.

Answer 2

Anything that goes into space needs to be robust enough to withstand cosmic rays. That's why computer chips that go into space are usually of the older variety with thicker connections.

Mechanical devices such as buttons and switches are more intuitive. You can feel them when they click into place. They don't change what they do because someone updated the software.

Some of this has to do with industrial psychology, for example, beer handles in bars to ensure that the bartender never pours the wrong beer. Those beer handles were traditionally installed in nuclear power plant control rooms (attached with electrical tape) to make sure somebody didn't pull the wrong switch at the wrong time.

If you can come up with a touch-screen design that has seen at least a billion hours of service (cumulative for all users) with absolutely no changes to the hardware or software, and if it's performed well, then maybe there would see the beginnings of a discussion.

Answer 3

The other thing to consider is in the zero gravity environment of outer space you don't want a floating or a fast flying item to accidentally hit a touch panel and inadvertently activate any of the craft's controls.