[SystemSafety] AVs vs. driver aids ... some more WTF questions

Olwen Morgan olwen at phaedsys.com
Tue Jul 23 15:13:17 CEST 2019


On 23/07/2019 13:14, Steve Tockey wrote:
> <snip>
>
> *) if you let human factors people design user interfaces, you will get user interfaces that are easy to use but very difficult to build.
>
> *) If you let technical people design user interfaces, you will get user interfaces that are easy to build but difficult to use.
>
> The proof is left to the reader of which of these two cases applies to the cars you refer to. . .

<snip>

AFAI can see, there's no inherent technical reason why easy-to-use UIs 
should be difficult to build. (OK, if you know HMI but are not a 
software engineer, you may find it difficult to build, but that's not 
the same issue.)

To my mind, a lot of design errors in HMIs arise from trying to 
shoe-horn the HMI code into the functional logic control flow or 
vice-versa. One way to avoid this is to design the HMI and functional 
logic as distinct communicating action systems. That way you can have 
optimal control structures for both at the expense of needing a 
communication protocol between them. You could build HMIs like this 
quite straightforwardly by using, for example, Tcl/Tk for the HMI and 
Erlang for the core logic. Indeed I'm inclined to think that requiring 
different languages for the HMI and functional logic would not be a bad 
idea since it would tend to force a design as two communicating actions 
systems.


FWIW,

Olwen




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