Ian Stirling | 5 Oct 17:15 2013

Re: The "open hardware" phone project that's had the most interest

On 10/05/2013 04:04 PM, Pascal Gosselin wrote:
> While I understand the needs/wants of open hardware, the average 
> smartphone user really couldn't care less. That's the core of the 
> problem, lack of a large user base.
> HOWEVER, what a *lot* people seem to be interested in, is an open 
> architecture MODULAR smartphone that could be customized.  You want a 
> bigger battery ?  A better GPS ?  A better camera ? Audio/video inputs 
> ?  Discrete inputs ?   Serial ports ?  Ethernet ? Absolutely !
> Close to 900,000 people have indicated current interest in making this 
> happen.
> http://www.phonebloks.com/
Unfortunately, it seems the technical understanding of the people 
involved is limited.
This is basically at the level of a 5-year-old trying to design a car.
'Ok - it needs wheels and doors and a ball-pit'. Without the knowledge 
of what the transmission or suspension is.

There are many challenges to making modular systems.
Let's consider a module - and not even go into specifics.

Firstly - you need to make it a given size - or it won't fit into the phone.
This means that either you make the modules large, and may waste space 
in them, or you make them small, and risk stuff not fitting.
Secondly, you add costs.
This starts at the connector(s) - fine pitch very dense connectors are 
expensive! Especially if they need to deal with RF - and fragile.
Another cost is overcapacity - if you have a phone, you can design the 
power supply to be adequate.
Overdesigning it to cope with upgrades costs money.
Now we run into the issue of reliability - part of the reason modern 
phones are comparatively reliable is they have almost no connectors.
Certainly none that require mating/unmating by the user.

Now, you also need to pay for extra antistatic components on each end of 
the module interface, a case for the module, a place in the phone for 
the module to fit in, and mechanical support so it doesn't fall out.
Then the issue of antennas arises.

Can it be done - sure!
Will it be twice the price, twice the weight, a quarter of the 
reliability - very likely.