[IxDA Discuss] Create winning HW/SW designs (was Re: Bill Moggridge talk at Ideo tonight)

[Bill DeRouchey]

On Sat, 4 Nov 2006, Edwin Booth wrote:

> A challenge with integrated hardware/software products is getting the 
> hardware and software teams to meaningfully collaborate - in a way that 
> actually blends the hardware and software design decisions. Peter's 
> inventory of the iPod UI/iTunes UI is interesting but it's all software. 
> There's nothing hardware about it - the main points of 
> hardware-to-software interface are the scroll wheel and the USB cable 
> (and of course the standard desktop controls).

Everything that happens onscreen is software, but the it's the 
layout/labeling/prominence of the controls (onproduct UI) that helps the 
user to understand how the onscreen UI works. The two halves of the UI 
must together form a coherent cognitive model for the user to 'get' the 
product.

To illustrate this how tight this connection must be, let's compare the 
iPod UI with the Tivo UI. The Tivo remote control navigation controls are 
a 4-way rocker plus an optional Select. The iPod also has a 4-way (not on 
a rocker) with a center Select, overlayed by a Scroll wheel.

List-based navigation must have methods to Scroll the options in the 
current list, Select the current option (which may be another list), or 
Return to the upper level ("go back", "go up").

Tivo and iPod handle this completely differently.

On Tivo, the cognitive model is that menus move horizontally. Deeper is 
to the right, higher to the left. Press the East button takes you to the 
right (deeper). Press the West button takes you to the left (higher). Up 
and Down let you Scroll in the list.

On the iPod, deeper is the center Select, higher is the North (menu) 
button. West and East do nothing. Scrolling is dragging circular around 
the wheel.

So cognitively, according to the controls pressed, Tivo menuing is a 
left/right model, while iPod menuing is an up/down model. However, both 
systems transition the menus with left/right animation, sliding left or 
right to indicate depth in the menu structure.

Cognitively, Tivo makes sense while iPod is disjointed. Sure, you -get- 
the iPod after a little use, but almost everybody is confused the first 
time they touch it.

This is an overly long way to come back to your point above and say that 
the UI is not only software. Even calling it hardware and software forces 
an artificial split. The UI is the whole product, the whole concept. 
Hardware and software are then components of the implementation once the 
concept and cognitive model are agreed upon by every one involved.

> Once those two things were decided the software and hardware could be 
> developed in isolation from one another.

Yes, once all the team members agree on the cognitive model, the basic 
behavior of the onscreen UI, and the layout of the hardware controls, then 
each team can figure out the details appropriate for their job title.

> Moreover, the decision on the 
> scroll wheel was probably not dependent on the design of the menuing 
> system - in all likelihood, the decision on the scroll wheel drove the 
> UI - but I haven't read the book on this one. Once you decide that the 
> device UI is a text-based menu, then you can send an IA-minded person 
> off to figure out the labels and the hierarchy.

> In this kind of situation, there's really not a lot of overlap between 
> the IA-minded folks and the hardware-focused folks.

The IA-minded people will likely own the structure of the menu, but you 
also want to make sure that you have an IA-type person when figuring out 
how to label your controls. Words? Icons? What's the most succinct? IA 
thinking can help everywhere.